Mosquito repellents tested: DEET is best; plant-based alternatives to it work fine in lower-risk areas if they are reapplied as needed

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By Immo A. Hansen and Hailey A. Luker

For The Conversation 

Now that summer is in full swing, mosquitoes have come out across the United States. The use of mosquito repellents can protect both your health and sanity this summer.

While mosquitoes leave bothersome, itchy bites on your skin, they can also pose a serious and sometimes deadly risk to your health. When a mosquito bites you, it may transmit harmful pathogens that cause dangerous diseases like malaria, Dengue fever, Zika and West Nile.

Avoiding mosquito bites

Mosquito females bite people to get vital nutrients from our blood. They then use these nutrients to make their eggs. One single blood meal can give rise to about 100 mosquito eggs that hatch into wiggling larvae.

There are several ways to avoid getting bitten by mosquitoes, from wearing long, loose clothing and limiting time outside to placing screens over your windows and getting rid of standing water that mosquitoes might use to breed.

However, one of the best ways to protect yourself when you’re going to a place where hungry mosquitoes will be buzzing around is by using mosquito repellents.

Our team at the New Mexico State University Molecular Vector Physiology Laboratory has studied different types of mosquito repellents and their efficacy for over a decade. Here’s what you need to know to protect yourself this summer:

All about repellents

The use of mosquito repellents goes far back in history, certainly predating written historical accounts. Some of the oldest records of the use of mosquito repellents date back to early Egyptian and Roman history. During this period, smoke from smudge fires was often used to repel mosquitoes.

Today, we have more options than our ancestors when it comes to choosing what type of mosquito repellent to use – sprays and lotions, candles, coils and vaporizers, to name some.

These repellents interfere with a mosquito’s sense of smell, taste or both. The repellent either blocks or overstimulates these senses. Scientists understand how certain repellents like DEET work at the molecular level, but for many of them, it is still unknown why exactly they repel mosquitoes.

Testing repellents

We used a variety of scientific laboratory experiments and field tests to find out what works. For some products, testing was as simple as putting a volunteer’s treated arm into a cage with 25 mosquitoes and waiting for the first mosquito bite.

For others, like citronella candles, we used a slow-speed wind tunnel and put a candle or device between a person and a cage of mosquitoes. Depending on the repellent efficacy of the device, mosquitoes either flew toward the person or away. Another experiment we conducted was the Y-tube choice assay where mosquitoes chose to fly toward someone’s hand or, if repelled, fly toward the blank or empty option.

Mosquito repellents that don’t work

Bracelets don’t work. Department stores and pharmacy chains sell hundreds of different varieties of bracelets. They are marketed as “mosquito repellent” bands, wristbands and watches, and their materials can vary from plastic to leather. Even if they are loaded with repellents, they can’t protect your whole body from mosquito bites.

Ultrasonic repellent devices don’t work. These come as electrical plug-ins, free-standing varieties or watchlike accessories that claim to emit a high-frequency sound that deters mosquitoes by mimicking bats. However, in scientific studies, ultrasonic repellent devices fail to repel mosquitoes. In fact, when our lab tested one of these devices, we found a slight increase in mosquito attraction to the wearer.

Dietary supplements – vitamin B, garlic and so on – don’t work. No scientific evidence shows these supplements protect people from mosquito bites.

Light-based repellents don’t work. These devices come as colored light bulbs, and they don’t attract insects that fly toward white light. This approach works well on moths, beetles and stinkbugs, but not on mosquitoes.

Mosquito repellents that work

And here is our ranking of what does work, starting with the best repellent/active ingredient:

• DEET works. DEET, chemical name, N,N-diethyl-meta-toluamide, was developed in the 1950s by the U.S. Army and is a well-established mosquito repellent with a long history of use. The higher the percentage, the longer the protection time is – up to six hours.
• Picaridin works. This synthetic repellent can protect for up to six hours at a 20% concentration. This repellent is a promising alternative for DEET.
• Oil of lemon eucalyptus, or OLE, works. OLE, with the active ingredient PMD, is a plant-based alternative to DEET and picaridin. Its repellent properties can last for up to six hours.
• Other essential oils – some work, some not so much. We applied 20 different essential oils in a 10% essential oil lotion mixture to volunteers’ skin. Here’s what we found: Clove oil works. This oil, with the active ingredient eugenol, can protect from mosquito bites for over 90 minutes at a 10% concentration in lotion. Cinnamon oil works. This oil, with the active ingredients cinnamaldehyde and eugenol, can protect from mosquitoes for over 60 minutes at a 10% concentration in lotion. Geraniol and 2-PEP, or 2-phenylethyl propionate, work for about 60 minutes at a 10% concentration in lotion. Citronella oil works, just not so great. We found citronella oil at a 10% concentration only protected from mosquito bites for about 30 minutes.

If you are planning to mix your own plant-based mosquito repellent this summer, remember that essential oils are complex mixtures of plant-made chemicals that can cause skin irritations at high concentrations.

Based on our study, we recommend using repellents with the active ingredient DEET if you live in or are traveling to regions with a high risk of vector-borne disease transmission. However, plant-based repellents will work just fine to prevent nuisance mosquito bites in low-risk areas, as long as you reapply them as needed.

Immo Hansen is a professor of biology at New Mexico State University, where he studies new ways to control vector-borne diseases. Hailey Luker is a Ph.D. biology student at New Mexico State. Her research ranges from repellent testing using ticks and mosquitoes to molecular research studying amino-acid transport proteins in mosquitoes.

West Nile virus report for Kentucky: four cases in humans, four in horses, and in some mosquitoes in Jefferson County

Four cases of West Nile virus have been found in Kentucky this summer: two in Hopkins County and one each in Jefferson and Fayette counties, the state Department for Public Health reported Friday. All were in adults. The number is below the annual average of 10 reported from 2012 to 2016.

All but eight states have reported cases of West Nile in people, horses, birds or mosquitoes this year, the department said. The virus is transmitted by mosquito bites. The Louisville health department recently found West Nile-infected mosquitoes in four Jefferson County ZIP codes (40204, 40205, 40206, 40208, 40212 and 40214), but there have been no other positive reports of mosquitoes with the virus in Kentucky.

“It’s common for us to find mosquitoes infected with West Nile in Louisville around this time each year. What this means is people should take the appropriate precautions, Louisville Health and Wellness Director Sarah Moyer told Darla Carter of The Courier-Journal.

The state health department says four horses have tested positive for West Nile, in Bourbon, Franklin, Hart, and Russell counties. The virus can cause severe illness in horses and certain species of birds, but does not usually affect domestic animals. There is no West Nile vaccine available for people, but several are available for horses, and owners are advised to vaccinate their horses annually.

In most human cases, infected people have no symptoms or show relatively mild symptoms, such as fever, headache, body aches, joint pains, vomiting, diarrhea, or rash. They typically recover on their own, though symptoms may last several weeks. Fewer than 1 percent will develop a serious illness such as encephalitis or meningitis. People over 50 and those with certain medical conditions, such as cancer, diabetes, hypertension, kidney disease and organ transplants, are at greater risk for serious illness if they contract West Nile.

The health department advises Kentuckians to avoid mosquitoes, particularly between dusk and dawn, when the insects are most active. It recommends these precautions:

Avoid Mosquito Bites

·        Use insect repellents when you go outdoors. Repellents containing DEET, picaridin, IR3535, and some oil of lemon eucalyptus and para-menthane-diol products provide longer-lasting protection. To optimize safety and effectiveness, repellents should be used according to the label instructions. More information about insect repellents can be found at http://www.cdc.gov/westnile/faq/repellent.html.

·        When weather permits, wear long sleeves, long pants and socks when outdoors. Mosquitoes may bite through thin clothing, so spraying clothes with repellent containing permethrin or another EPA-registered repellent will give extra protection. Don't apply repellents containing permethrin directly to skin. Do not spray repellent on the skin under your clothing.

Mosquito-Proof Your Home

·        Install or repair screens on windows and doors to keep mosquitoes outside.

·        Help reduce the number of mosquitoes around your home by emptying standing water from flowerpots, gutters, buckets, pool covers, pet water dishes, discarded tires and birdbaths on a regular basis.

More information can be found online at: https://www.cdc.gov/westnile/ or http://www.chfs.ky.gov/dph/epi/westnile.htm. 

The Zika virus has come to Ky. through travelers, and could spread at any time, but few people know or do much about it

This species of mosquito carries Zika.

By Melissa Patrick
Kentucky Health News

As temperatures and travel increase, so does the possible threat from the Zika virus, which can cause dangerous or even deadly birth defects, but many potential victims are uninformed and unprepared.

The best prevention for now may be vigilance by property owners against standing water where mosquitoes breed. Experts say those who travel to Zika-affected areas such as Florida and Texas should use insect repellents after they return to keep local mosquitoes from picking up the virus, which causes no symptoms in some people.

Nearly two out of five people who had traveled to an area affected by the Zika virus hadn't heard or seen any information about how to protect themselves or others from it, and even those who knew how to protect themselves didn't always do so, according to a recent poll.

A senior research scientist at the Harvard T.H. Chan School of Public Health presented the poll results at the 2017 Zika Conference in Lexington May 11. Dr. Gillian SteelFisher said the results emphasized the need for more preventive education, noting that many people don't realize that it "just takes one bite" to become infected.

A Kentucky study of 55 women of childbearing age who had traveled to Zika-affected areas found a similar need for more information, especially among Spanish-speaking women with less education under the age of 30, said Kristen Heitzinger, a Centers for Disease Control and Prevention fellow at the state Department of Public Health.

State Health Secretary Vickie Yates Brown Glisson called on the more than 400 conference attendees to go back to their communities and become "unwavering" in their efforts to get and deliver a simple, easy-to-understand message about Zika, its dangers and how to fight it.

Dr. Ardis Hoven (file photo)

State infectious disease specialist Dr. Ardis Hoven told the conference that local health departments will educate community leaders about the virus. For an 86-second audio clip of her remarks, via Stu Johnson of WEKU, click here.

"Our research tells us that not nearly enough pregnant women in particular, or those who are of the age to become pregnant, know about the Zika virus and what they should do to protect themselves and their unborn baby, or a potential unborn baby," Glisson said. "Overwhelming evidence has shown a link between Zika and dangerous birth defects that cause delayed development and sometimes even death in infants."

Zika is spread mostly by the bite of an infected mosquito, though it can also be transmitted through sex, and from a pregnant woman to her fetus. It circulates in many parts of the world where Kentuckians vacation, do mission trips or work.

So far, only Florida and Texas have had locally transmitted infections in the U.S., but Kentucky has the mosquito that is known to carry it. Click here to see the locations where Zika is a risk.

The virus can cause microcephaly, a condition where a baby's head is smaller than normal because the brain does not develop properly, and other birth defects in infants born to women infected during pregnancy.

It is also associated with adult Guillain-Barre syndrome, a rare disorder in which the body's immune system attacks its nerves.

The most common symptoms of Zika are fever, rash, joint pain and red or burning eyes, though many who are infected have few if any symptoms, which can be so mild they go unrecognized.

There is no vaccine to prevent Zika, and no antiviral treatment for it.

According to the CDC, 5,000 cases of Zika have been identified in the U.S. and its territories including 37 in Kentucky and 1,367 in pregnant women. Among those women, 65 gave birth to babies with some type of Zika-related birth defect.

Of the 37 Kentucky cases, four were pregnant women whose children have had no complications, but are still being monitored. All the Kentucky cases were a result of travel to Zika-affected areas or through having sex with someone who had traveled to those areas.

The state health department has adopted the tag line "Dress, Drain and Defend -- to Fight the Bite Day and Night" to help Kentuckians remember to be vigilant about mosquito control:

• Dress in light-colored, long-sleeved shirts and pants;
• Drain all standing water where mosquitoes can breed, such as birdbaths, tires, buckets, gutters and anything, however small, that may act as a vessel for rainwater;
• Defend against mosquitoes with approved insect repellents for outdoor activities at all times.

Luke Mathis, the environmental health supervisor at the Lexington Fayette County Health Department, said citizens must do their part to make sure Kentucky doesn't have a Zika outbreak.

"We could work ourselves to exhaustion, we could spend every dime of money, and it would have little effect on the mosquito population," Mathis said. Instead, he said it would be more effective to "have every homeowner check out their yard for a few minutes every couple of weeks and kick over those buckets or get rid of those tires."

"We need to begin changing people's attitude to make it socially unacceptable to breed mosquitoes in and around their property," Brown said. "It's going to take decades."

The state health department has advice for those considering travel to Zika-affected areas:

• Pregnant women and their partners should not travel to Zika-affected areas;
• Consult with a health-care provider prior to travel if you are pregnant or planning to conceive;
• Couples who are planning to become pregnant should postpone conception for six months after travel to a Zika-affected area, and should discuss plans for pregnancy with their health provider
• Follow steps to prevent mosquito bites: Dress and defend!
• Wear a condom every time you have sex, including vaginal, oral and anal sex, or practice abstinence, while in a Zika-affected area.

Advice for those who have been to a Zika-affected area after they get home:

• Women who have been exposed to the virus should use condoms or abstain from sex for at least eight weeks after symptom onset or last possible exposure.
• Men who have been exposed to the virus should use condoms or abstain from sex for at least six months after symptom onset or last possible exposure.
• Male travelers with pregnant partners should wear condoms throughout the pregnancy.
• Travelers to Zika-affected areas who have symptoms within two weeks of their return to Kentucky should contact their health-care provider.
• Travelers returning from Zika-affected areas should wear mosquito repellent for three weeks after returning, so they won't infect other mosquitoes that could bite others.
• Remember that these precautions are necessary because many infected people have no symptoms.

Dr. Grayson Brown, professor of entomology at the University of Kentucky and director of the Public Health Entomology Laboratory, said many people are concerned about the safety of insecticides, but that they shouldn't be. He said "insecticide technology has changed" in the last 50 to 60 years and that products today are "nontoxic to humans and other vertebrates, but so powerful against mosquitoes."

"If we don't use them," Brown said, "the suffering is going to be absolutely enormous." He said South Florida officials averted a crisis last summer by using insecticides to kill Zika-carrying mosquitoes. Without that, there could have been "hundreds of thousands of cases, and thousands of micrcocephalic babies. . . . They avoided a serious, serious public-health crisis."

Kentucky sprays for mosquitoes each year, but Brown said the spray in mosquito trucks kills very few Zika-carrying mosquitoes, which require a different product that is hand-applied under bushes and brush.

For further information or to sign up for health alerts, visit http://healthalerts.ky.gov/zika or the CDC website at www.cdc.gov/zika. The UK College of Agriculture, Food and Environment website also offers Zika updates.

UK entomologist says Ky. not likely to have Zika outbreak this year, but state still sprays around homes of those few with virus

Aedes Aegypti mosquito (CDC photo)

An entomologist from the University of Kentucky encourages Kentuckians to stay calm about the Zika virus because Kentucky does not have many of the mosquitoes known to transmit the disease, and therefore is not likely to have an outbreak.

"Keep calm, don’t overreact and enjoy what’s left of summer. Zika is not likely to cause a mosquito-borne outbreak in Kentucky in 2016," Grayson C. Brown, director of the Public Health Entomology Laboratory at the university, wrote in an op-ed for the Lexington Herald-Leader.

The op-ed comes on the heels of the federal Centers for Disease Control and Prevention reporting that the Zika virus is being locally transmitted between humans and mosquitoes in southern Florida.

Grayson explains that the mosquito that transmits Zika, the Aedes aegypti or yellow-fever mosquito, was common in Kentucky until the mid 1980s. But since, it has been replaced by the Aedes albopictus, or the Asian tiger mosquito. He wrote, "Over the last two years, we have only found four out of over 26,000 mosquitoes caught."

"The significance of Asian tiger mosquitoes replacing yellow-fever mosquitoes here is that Asian tiger mosquitoes either do not transmit Zika or are much less efficient at it," he wrote. "Lacking the principal vector, we do not expect a significant outbreak of Zika in Kentucky this year."

He also noted that mosquito season is coming to an end, which will decrease any further threat of a Zika local outbreak.

Meanwhile, the state Department of Agriculture sprayed an insecticide for adult mosquitoes around the home of an Alexandria resident who contracted the Zika virus while traveling outside the country, Chris Mayhew and Anne Saker report for The Kentucky Enquirer. Mosquitoes can pick up the virus by biting infected people, then transmit it to others.

City officials were upset that they weren't told about the spraying. The Northern Kentucky Health Department cited privacy concerns. “The spraying is done in such a concentrated area, a matter of blocks, around the affected person, that to identify the neighborhood would likely be a violation” of the federal patient- privacy law, said Emily Gresham Wherle, spokeswoman for the department.

Grayson urged Kentuckians to not overreact and to use "common-sense mosquito-avoidance techniques" like using a repellent only when necessary, emptying containers that hold water and to avoid being outdoors between 4 p.m. and 9 p.m., when mosquitoes are most active.

He also reminded Kentuckians that state and local health departments have been preparing for Zika since last October and have developed rapid-response teams to respond to an outbreak if it occurs.

But he also told Kentuckians to stay informed because "next year may well be a different story."

"Zika has proven to be difficult to predict, as it has mutated. It may well jump to another mosquito more common here. If we start seeing significant caseloads in Georgia, for instance, we’ll have to go on alert here," he wrote.

Grayson cautioned travelers to Zika-infected areas, especially pregnant women and women who plan on becoming pregnant, to follow the CDC guidelines for how to prevent mosquito bites and how to practice safe sex both during and after travel.

McConnell continues to blame Democrats for lack of Zika funding, not mentioning details of what they call GOP 'poison pills'

By Al Cross
Kentucky Health News

As the Zika virus spreads in Florida, Senate Majority Leader Mitch McConnell of Kentucky continues to press his argument that Senate Democrats are responsible for the lack of funding to fight it. But as with most political arguments, the latest column he sent Kentucky newspapers left out some details.

Senate Democrats did block a bill with $1.1 billion in Zika funding, saying Republicans had added "poison pills." The one that got the most attention was a provision to prevent Planned Parenthood from receiving any funding for birth control in Puerto Rico, where there is an epidemic of the virus, which causes a serious birth defect and can be spread through sexual contact.

McConnell didn't get that specific in his column, but wrote: "Democrats continue to make a lot of excuses for their vote, but it seems apparent they’re answering to the beck and call of a third-party interest group—Planned Parenthood. The common-sense bill that Senate Republicans proposed does not prohibit funding or deny access for birth control. In fact, it would expand access to women’s health care through Medicaid, community health centers, public health departments, and hospitals rather than earmarking those resources to one controversial interest group."

Democrats also objected that the bill, primarily for military construction and veterans, did not include a provision banning display of the Confederate flag at federal veterans' cemeteries, "a ban that the House, including 84 Republicans, voted in favor of just a month earlier," Amber Phillips notes for The Washington Post. That's fewer than a third of House Republicans, and the House-Senate conference committee was dominated by Republicans on both sides. It also added restrictions on Obamacare spending and other provisions Republicans liked.

"House leaders shaped the bill so that a majority would vote for it; in a conservative House, that meant making the bill more amenable to conservatives" who don't like additional spending, Phillips writes. "The end result was a proposal Democrats said was untenable."

Meanwhile, the urgency grows. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said on CBS's "Face the Nation" Sunday, "We're gonna rapidly run out of money if we don't get to real soon. . . . We're getting to that critical point very quickly."

Fauci said, however, that outbreaks of Zika are likely to be spotty. "We don't believe it's going to be widely disseminated." He said the most important thing to keep the virus in check is aggressive control of mosquitoes and the standing water where they lay eggs.

Rogers, other Republicans agree on $1.1 billion to fight Zika, but Democrats don't like where the money would come from

U.S. Rep. Hal Rogers of Somerset and other Republican leaders in Congress "are closing in on a $1.1 billion funding deal to combat the Zika virus, but Democratic leaders are threatening to oppose it over cuts to crucial health-care programs," Sarah Ferris reports for The Hill.

Rogers, the chair of the House Appropriations Committee, and his Senate counterpart, Mississippi Republican Thad Cochran, are trying to meet GOP leaders' goal to approve a Zika funding bill by the July 4 holiday recess. They "expect to finalize a deal on the long-awaited funding package sometime Wednesday evening, according to their offices," Ferris writes.

A Democratic aide told Ferris that the deal would use the Senate’s figure of $1.1 billion, more than double what the House approved, but "would use many of the controversial offsets used in the House Republicans’ bill, such as money for the Ebola virus response and programs under Obamacare. It would also include politically thorny restrictions targeting funding for women's health programs." President Obama has asked for $1.9 billion.

Senate Democrats threatened to block the bill, saying "they’ve been frozen out of the talks," Ferris reports. “There is no bipartisan 'deal' on Zika. The only 'deal' is House and Senate Republicans agreeing to launch more attacks on women's health,” Adam Jentleson, a spokesman for Senate Minority Leader Harry Reid, tweeted Wednesday. Jentleson also called the GOP proposal “deeply unserious.”

Obama asks public to tell Congress to fund the $1.9 billion Zika fight he wants; Senate passed $1.1 billion, House $622 million

The Zika funding package of Appropriations Committee Chair Hal Rogers and other House Republicans "doesn't make a lot of sense" and the somewhat larger Senate package backed by Majority Leader Mitch McConnell and a bipartisan Senate majority falls well short of what is needed, President Obama told reporters Friday.

The Senate has passed a $1.1 billion package and the House approved $622 million. Obama wants more than three times the House figure, $1.9 billion, to fight the virus that causes a serious birth defect.

"We didn’t just choose the $1.9 billion from the top of our heads," Obama said. "This was based on public-health assessments of all the work that needs to be done. And to the extent that we want to be able to feel safe and secure, and families who are of childbearing years want to feel as if they can have confidence that when they travel, when they want to start a family that this is not an issue -- to the extent that that's something that we think is important, then this is a pretty modest investment for us to get those assurances."

Obama said the House package is not only inadequate, "That money is taken from the fund that we're currently using to continue to monitor and fight against Ebola. So, effectively, there’s no new money there. All that the House has done is said, you can rob Peter to pay Paul. And given that I have, at least, pretty vivid memories of how concerned people were about Ebola, the notion that we would stop monitoring as effectively and dealing with Ebola in order to deal with Zika doesn’t make a lot of sense."

The president added, "This is something that is solvable. It is not something that we have to panic about, but it is something we have to take seriously. And if we make a modest investment on the front end, then this is going to be a problem that we don't have to deal with on the back end." He said each child who has a small brain as a result of Zika "may end up costing up to $10 million over the lifetime of that child in terms of that family providing that child the support that they need. . . .  It doesn’t take a lot of cases for you to get to $1.9 billion. Why wouldn't we want to make that investment now?"

Part of the money would go to develop a vaccine for Zika, and part of that work is going on at the University of Kentucky. "You don't get a vaccine overnight," Obama said. "You have to test it to make sure that any potential vaccine is safe. Then you have to test to make sure that it's effective. You have to conduct trials where you're testing it on a large enough bunch of people that you can make scientific determinations that it's effective. So we've got to get moving."

Obama said the Centers for Disease Control and Prevention and the National Institutes of Health are "taking pots of money from other things -- universal flu funds or Ebola funds or other funds -- just to get the thing rolling. But we have to reimburse those pots of money that have already been depleted and we have to be able to sustain the work that’s going to need to be done to finish the job. So, bottom line is, Congress . . . needs to get me a bill that has sufficient funds to do the job."

The president said that should happen before the summer congressional recess in August, "to provide confidence to the American people that we're handling this piece of business." He said the money would be insurance for young families or couples thinking about having children.

"To the extent that we're not handling this thing on the front end, we're going to have bigger problems on the back end," Obama said. "Tell your members of Congress, get on the job on this. This is something we can handle. We should have confidence in our ability to take care of it. We've got outstanding scientists and researchers who are in the process of getting this done, but they’ve got to have the support from the public in order for us to accomplish our goal."

Ky. has plan to keep Zika virus out of state, but needs your help; travelers to Zika-affected areas need to take precautions

By Melissa Patrick
Kentucky Health News

State officials launched a mosquito prevention campaign May 9 at the Kentucky State University Research Farm near Frankfort as part of the state's efforts to combat the Zika virus, with an emphasis on the need for Kentuckians to do their part at home and when they travel.

"Zika prevention is mosquito prevention," Health Secretary Vickie Yates Brown Glisson said at the news conference where she introduced the campaign, "Fight the Bite Day and Night."

To date, six cases of Zika have been confirmed in Kentucky, all in people who were infected abroad and then returned to the U.S. But Glisson said it is "very possible" that Kentucky could have a local outbreak because the state has the species of mosquito that transmits the virus.

Of the 59 mosquito species in Kentucky, only one, Aedes aegypti, a small, black mosquito that bites mostly during the day, has been confirmed as a Zika carrier, and it is "very rare," accounting for "roughly one out of every 5,000 or so mosquitoes that we catch here in Kentucky," said Grayson Brown, director of the Public Health Entomology Laboratory at the University of Kentucky. However, Brown said six or seven other species in the state could be Zika transmitters, including the state's most common monquito, Aedes albopictus, better known as the Asian tiger mosquito.

The major concern is that a Zika-infected person will return to the U.S., get bitten by a mosquito that can transmit it to the next person it bites, with the cycle continuing.

Symptoms of the virus include fever, rash, joint pain and red eyes, although about 80 percent of people who are infected with the Zika virus never show symptoms.

Those in greatest danger from the infection are women in early pregnancy. Infants born to Zika infected mothers are at high risk for microcephaly, a condition where the infants head is smaller than normal, as well as other possible severe fetal brain defects. It has also been associated with Guillain-Barre syndrome, a rare disorder in which the body's immune system attacks its nerves, in adults. The World Health Organization has declared Zika an international health threat.

Dr. Ardis Hoven, infectious disease specialist with the Kentucky Department of Public Health, urged travelers to protect themselves from mosquitoes by using EPA-approved repellents and wearing protective clothing while in affected areas, and doing so for three weeks after returning home to prevent transmission to local mosquitoes.

"If everyone does this, it greatly reduces the risk of Zika ever getting into Kentucky's mosquito population," said Hoven, who is also chair of the World Medical Association. "We are counting on you, so please take this advice seriously."

The state has created an extensive action plan to monitor Zika infected mothers and their infants that includes a monitoring schedule, and access to many social and healthcare services as needed. The state health department has reported that one of the confirmed Zika cases in the state is a pregnant woman.

Hoven advised pregnant women to not travel at all to affected areas and specifically said, "Pregnant women should not attend the Olympics," which will be held in Rio de Janeiro in August.

Concerns about Zika in Rio prompted Amir Attaran, a professor in the School of Public Health and the School of Law at the University of Ottawa, to write a commentary for the Harvard Public Health Review, calling for the Olympic Games to either be postponed or moved to another country.

"Does it really make sense to send a half-million [Olympic tourists] into Rio, which is, to be very clear, not the fringes of the outbreak? It's the heart of the outbreak," Attaran told NPR. "But is it at the end of the day sensible to run the risk of a global epidemic of, let's face it, brain-damaged babies, when that could be avoided by simply postponing the games or moving them elsewhere?"

Attaran, whose wife is from Brazil, told NPR that while the risk is quite low for individual athletes or individual tourists, "when you multiply (that) by 500,000, the odds are extremely high that somebody will take the disease elsewhere and seed a new outbreak."

Zika can also be transmitted sexually, which has occurred about 10 times now in the United States, Hoven said.

Shelley Wood, nurse consultant for Zika at the state health department, said male travelers without symptoms should use condoms for eight weeks after departure from a Zika-affected area. Men with Zika symptoms should get tested and use condoms for six months, and male travelers with pregnant partners should wear condoms throughout the pregnancy .

Wood also said couples should take steps to prevent conception for at least eight weeks after returning from a Zika-affected area, and women should not travel to such areas eight weeks before they are trying to conceive.

State officials urged Kentuckians to be vigilant about mosquito control and reminded them to remember the "3 D" approach to decrease the risk of infection by mosquitoes:

• Drain all standing water where mosquitoes breed such as bird baths, tires, buckets and gutters
• Defend against mosquitoes with approved insect repellents at all times for outdoor activities.
• Dress in light colored long sleeved shirts and pants.

State Agriculture Commissioner Ryan Quarles announced a partnership between his Agriculture Department and the health ahency as part of its Zika prevention plan. This partnership allows health officials to mobilize "strike teams" and use Agriculture Department equipment if the state begins to have local transmissions of Zika. Typically, the Agriculture Department sprays for mosquitoes at the request of local officials or local health departments.

Hoven said, "As with all public health issues, the best form of protection is prevention, not clean-up."

The University of Kentucky College of Agriculture website has the latest updates on Zika and its spread.

Zika update: Local anti-mosquito action needed; McConnell, Rogers at center of debate over Obama's request for more funds

Mosquitoes can carry Zika. (NPR photo)

By Melissa Patrick
Kentucky Health News

While all 388 Zika virus cases confirmed in the continental U.S., including six in Kentucky, have been in people who were infected abroad and then returned to the states, a health official said on "Fox News Sunday" that it is likely the U.S. will have its own outbreak.

"It is likely we will have what is called a local outbreak," said Dr. Anthony Fauci, director of the U.S. National Institute of Allergy and Infectious Diseases, Diane Bartz reports for Reuters.

Fauci said he did not expect a large number of people to become ill: "We're talking about scores of cases, dozens of cases, at most."

Dr. Ardis Hoven, infectious disease specialist for the Kentucky Department for Public Health, agreed and said the potential exists for Kentucky to have a local outbreak.

"I think it would be unreasonable for us to assume that we would not be at risk," she said in a telephone interview. "So therefore, we have to plan accordingly."

Hoven said mosquito control in the state is a "top priority," but said the bulk of this will have to happen at a local level.

She encouraged Kentuckians to talk about mosquito prevention with their friends and family and ask themselves, "What can I do in my community, in my yard, on my street to prevent mosquitoes from hatching and infecting those around me?"

Zika virus prevention strategy: Dress, Defend and Drain

The state has adopted a "3 D" approach to decrease the risk of infection by mosquitoes: Dress in light-colored long sleeved shirts and pants; Defend against mosquitoes with approved insect repellents; and Drain all standing water.

"If we can control mosquitoes in our region, we will go a long way to minimize the potential risk from infected mosquitoes," Hoven said.

The World Health Organization declared Zika a global health emergency in February. Those who have traveled to affected areas, such as Central and South America, are at the highest risk of contracting the virus, which is spread primarily by infected Aedes aegypti mosquito. It can also be spread through sexual intercourse. Aedes aegypti can be found in about 30 U.S. states, including Kentucky.

Zika virus is especially dangerous to pregnant women because it has been linked to thousands of cases of microcephaly, a condition where the infants head is smaller than normal, as well as other severe fetal brain defects, according to the federal Centers for Disease Control and Prevention. The state health department has reported that one of the confirmed Zika cases in the state is a pregnant woman.

The CDC is investigating the link between Guillain-Barre syndrome, a rare disorder in which the body's immune system attacks its nerves. And Fauci said there could be other neurological conditions caused by Zika that affect adults, Bartz reports.

"There are only individual case reports of significant neurological damage to people, not just the fetuses, but an adult that would get infected. Things that they call meningoencephalitis, which is an inflammation of the brain and the covering around the brain, spinal cord damage due to what we call myelitis," Fauci said. "So far they look unusual, but at least we've seen them and that's concerning."

Common symptoms of the virus are fever, rash, joint pain and red eyes, with symptoms lasting for about a week, though many with the virus have no symptoms. Currently there is no vaccine for Zika.

Funding to fight Zika held up in Congress

In February, President Obama asked Congress for an additional $1.9 billion in emergency funds to fight the Zika virus, including funds to develop a vaccine. This is in addition to $589 million in previously appropriated funds that have already been transferred to the effort.

That money should last through Sept. 30, the end of the federal fiscal year, but "There's going to need to be additional money, I don't think there's any doubt about that," Rep. Tom Cole, R-Okla., who chairs the House health appropriations subcommittee, told Susan Cornwell of Reuters April 13.

Top senators from both parties said "they are getting close to a deal to provide at least some emergency funding to fight the Zika virus, making it likely that the Senate will move ahead on the issue without waiting for the House," David Nather writes for STAT, an online health journal.

Senate Majority Leader Mitch McConnell, R-Ky., said at a news conference April 19 that congressional Republicans were working with the administration on the funding details, Peter Sullivan reports for The Hill.

“We're working with them on it to figure out exactly the right amount of money,” McConnell said at a press conference. “You know, how is it going to be spent? And I don't think, in the end, there will be any opposition to addressing what we think is going to be a fairly significant public health crisis."

Nevertheless, House Republicans kept saying they don't have enough information to approve the request.

On April 20, House Appropriations Committee Chairman Hal Rogers, R-Ky., said the Obama administration “continues to delay response efforts by refusing to provide basic budgetary information to Congress on their Zika funding request. This includes not answering our most basic question: ‘What is needed, right now, over the next 5 months in fiscal year 2016, to fight this disease?’ In the absence of this information, the House Appropriations Committee will work with our colleagues in the House and the Senate to make our own determinations on what is needed and when, and to provide the funding that we believe is necessary and responsible.”

Five days earlier, White House Press Secretary Josh Earnest said Republicans have all the information they need to move forward, ABC reports. He said, “They've had ample opportunity to collect information, to ask questions of senior administration officials, to read letters, to read the legislative proposal that was put forward by the administration.” 

First case of Zika confirmed in Ky., from traveler to Central America; no threat to Kentuckians unless they visit affected areas

By Melissa Patrick
Kentucky Health News

After the first case of Zika was confirmed in Kentucky March 9, health officials held a news conference at the Capitol to raise awareness of the virus, noting that the state was coming up on the spring travel season.

Mosquitoes carry Zika. (CNN image)

Gov. Matt Bevin, Health Secretary Vickie Yates Brown Glisson and Dr. Kraig Humbaugh, senior deputy commissioner of the Department for Public Health, emphasized that only those who have traveled to affected areas, like Central and South America, need to worry about contracting the virus, which is commonly transmitted through mosquitoes.

"Many areas, including most of our surrounding states, are reporting Zika cases," Humbaugh said in the news release. "For now, these positive results have only occurred in individuals who have traveled outside the country to places where the virus is currently spreading."

The infected male patient in Kentucky had recently returned to Louisville from Central America. Humbaugh said he presented with signs of fever and rash, which a "very astute" health-care provider suspected as symptoms of Zika.

Common symptoms of the virus are fever, rash, joint pain and red eyes,with symptoms lasting for about a week, according to the U.S. Centers for Disease Control and Prevention. Although many with the virus will not show symptoms, Humbaugh said.

Health officials stressed that Kentucky is not at risk, but said the state has a plan in case the Zika virus spreads. Glisson encouraged health-care providers to be alert to the symptoms of the virus.

She also noted that the Cabinet for Health and Family Services was partnering with Kentucky Emergency Management and the Kentucky Department of Agriculture to increase the monitoring and control of the state's mosquito population this year.

The CDC recommends that pregnant women or those trying to become pregnant postpone travel to affected areas. However, if they must travel to one of these areas, the CDC asks them to talk to their healthcare provider before they leave and strictly follow steps to avoid mosquito bites during the trip.

Humbaugh noted that increasing evidence has found a link between infection in pregnant women and infants born with microcephaly, a condition where the infants head is smaller than normal, which can lead to a variety of other health challenges.

The Washington Post reports that the Zika virus has "growing links to a broad array of birth defects and neurological disorders ... worse than they originally suspected, increasing the risk for devastating harm during pregnancy."

Until Zika, "there has never been a mosquito-borne virus that could cause serious birth deffects on such a large scale," CDC Director Thomas Frieden told reporters.

There is no vaccine or treatment for Zika.  The virus can also be spread through sexual intercourse, and it is still unknown how long the virus stays in semen, Humbaugh said.

Kentucky has at least one mosquito known to transmit Zika.

“We do have Aedes aegypti, but  they are a very small populations, from what I understand from our mosquito experts,” Humbaugh said. “Our entomologists at the University of Kentucky have been advising us on this particular area. However, we have other types of mosquitoes that may be what they call competent vectors. In other words they may be able to spread the disease, but at this point that hasn’t been shown that these other mosquito types are competent vectors.”

Humbaugh encouraged Kentuckians to take normal precautions to limit exposure to mosquitoes like using approved insect repellents, wearing long sleeves and pants when outdoors, to stay inside during dawn and dusk when mosquitoes are most active, minimize standing water and screening windows.

More information about Zika can be obtained from the department's Health Alerts website at http://healthalerts.ky.gov/Pages/Zika.aspx. For a full list of affected countries and regions visit http://www.cdc.gov/zika/geo/index.html.

Zika virus, which can cause small heads and brains in newborns, will get to Kentucky, but experts disagree on its likely impact

The Zika virus that has been linked to birth defects (abnormally small heads and brains in newborns) is exploding in South America and will eventually show up in Kentucky, but its impact in the state is hard to predict.

The virus, for which there is no cure or vaccine, "seems destined to reach the United States, and probably sooner rather than later," Lena H. Sun and Brady Dennis report for The Washington Post. "What is far less certain, say public health and infectious disease experts, is Zika’s potential reach and impact here. The South is seen as especially vulnerable because of its warm, humid climate and pockets of poverty where more people live without air conditioning or proper window screens. Plus, the region is already home to mosquitoes that can transmit the virus."

The mosquito of main concern, the Asian tiger mosquito, has been reported many times in Kentucky; one of potential concern, the yellow-fever mosquito, has been reported in Indiana.

Washington Post graphic emendated by Kentucky Health News

"Nearly three dozen cases have been confirmed to date in 11 states and the District of Columbia," but the federal Centers for Disease Control and Prevention "acknowledges that the number is growing rapidly," the Post notes. "In each, the person was believed to have been infected while out of the country." The CDC has extended its travel warning northward to the Caribbean.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, "is playing down the potential for a significant eruption of Zika here," the Post reports. "He notes that dengue and chikungunya, diseases transmitted by the same kinds of mosquitoes, are widespread in Latin America, but their foothold in the United States has been controlled, with only small clusters of cases."

However, Peter Hotez, dean of the National School of Tropical Medicine at Baylor University in Waco, Texas, told the Post, “I think we’re in for real trouble in the United States,” because Zika can spread quickly. "He focuses on conditions throughout the Gulf Coast, where stagnant water sources — in uncollected garbage, discarded tires, untended bird baths — can be ideal breeding grounds for mosquitoes much of the year."

Tips on how to avoid getting bitten by mosquitoes

By Melissa Patrick
Kentucky Health News

Spending time outdoors is one of the great pleasures of summer. Unfortunately, this is also the active season for the 50 mosquito species that call Kentucky home. These mosquitoes are more than just a nuisance; some carry disease, making it important to protect yourself from them.

Photo from cdc.gov

Chikungunya is the latest mosquito-born virus transmitted in the U.S., although most cases in the U.S. are still caused by infections acquired from travel to the Caribbean, South America or the Pacific Islands, according to the federal Centers for Disease Control and Prevention. It is rarely fatal, but commonly causes fever, severe joint pain and other symptoms.

Kentucky had 17 confirmed cases of Chikungunya last year as well as eight probable ones, all in residents who had traveled recently to the Caribbean. and none of the cases were fatal. The state also had three confirmed cases of other mosquito-borne illnesses in 2014, including two dengue fever cases and one West Nile case, according to the Kentucky Cabinet for Health and Family Services.

Repellents

Insect repellents are your best guard against mosquitoes.

Four products have been registered with the U.S. Environmental Protection Agency for use as mosquito repellents: DEET (diethyltoluamide), picaridin, IR3535, and some oil of lemon eucalyptus and para-menthane-diol products.

Consumer Reports tested 15 products that represented each of these recommended repellents by spraying the products on the forearms of the testers, waiting 30 minutes, exposing their forearms to mosquitoes and ticks, and then measuring the number of bites every hour.

Based on this experiment, the magazine recommended Sawyer Fisherman's Formula (20 percent picardin) and Repel Lemon Eucalyptus (30 percent oil of lemon eucalyptus) as its first and second choice for repellents.

"It was the first time in the history of Consumer Reports testing insect repellents that the non-DEET formulations did better than the deet products," Sue Byrne, the magazine's senior editor of health and food, told Darla Carter of The Courier-Journal.

These products were followed by Repel Scented Family (15 percent DEET); Natrapel 8 Hour ( 20 percent picardin); and Off! Deepwoods VII (25 percent DEET).

Read the Labels

The U.S. Food and Drug Administration strongly recommends that you read the labels of all insect repellents before use and then use them as instructed, paying careful attention to the age limitations and precautions.

"As long as you read and follow label directions and take proper precautions, insect repellents with active ingredients registered by the U.S. Environmental Protection Agency do not present health or safety concerns," according to the FDA website.

Multiple sources say it is also important to not use combination products that contain both sunscreen and insect repellent. Sunscreen is meant to be applied often, while insect repellent is meant to be used sparingly.

High doses of DEET have been known to cause rashes, disorientation and seizures, according to the U.S. National Library of Medicine.

The FDA also notes that concentrations of any of the active ingredients above 50 percent "generally do not increase protection time" and that products with less than 10 percent of the active ingredient "offer only limited protection, about one or two hours."

Insect repellents and children

Adults should always apply insect repellents for children, making sure they don't get any on their hands, around their eyes, on any cuts or irritated skin. Spray repellents should always be applied outdoors, to avoid inhaling them.

The FDA recommends that DEET not be used on children under 2 months of age and that oil of lemon eucalyptus products not be used on children under 3 years old.

The American Academy of Pediatrics recommends that products with more than 30 percent DEET not be used on children, and that you use just enough repellent to cover exposed skin. It also recommends immediately washing off the repellent, and washing any clothes worn while exposed to the repellent, before wearing them again.

KidsHealth recommends that if you use DEET products on children, you should adjust the concentration of product by the number of hours your kids will be outside, using a lower concentration if they are only out for an hour or two and a higher concentration, which will last longer, if they will be out longer.

Non-repellent protections

In addition to advice on repellents, the University of Kentucky College of Agriculture, Food and Environment's Entomology Department website offers these suggestions to avoid mosquitoes:

• Minimize the standing water around your house; this is where mosquitoes breed.
• Use larvicides if it is impractical to eliminate a breeding site.
• Remove tall weeds and overgrowth in your yard; mosquitoes like to rest here during the day
• Keep windows, doors and porches tightly sealed and keep your screens in good repair.
• Stay indoors during the evening hours.
• Wear long-sleeved shirts and pants when outdoors.

UK Entomology says most devices that claim to attract, repel or kill mosquitoes don't work, or are unproven. It says "bug zappers" kill only a small percentage of mosquitoes, and studies have found that portable electronic devices using high-frequency ultrasonic sound are "of negligible benefit in deterring mosquitoes and reducing bites." The website does say that citronella oil offers "a degree of protection," but you need multiple candles to be effective.

Some odors we emit make us more attractive to mosquitoes; various repellents, including plant oils, are available

Mosquitoes are attracted to some people more than others because of skin odors or chemicals they emit, Jill Richardson writes for Salon. Carbon dioxide, heat, moisture, scent and appearance attract mosquitoes, but it's the chemicals you emit that make them want to take a bite, she writes.

Photo from Lexington Herald-Leader

Kentucky has about 60 of the 150 species of mosquitoes found in the U.S., according to the University of Kentucky Public Health Entomology Laboratory. Not all bite, and if one does, it is always a female, which needs the protein found in blood to make her eggs, UK extension entomologist Lee Townsend writes in The Courier-Journal.

Each species differs in biting persistence, habits and ability to transmit disease and even flying ability, Richardson writes, but it is the chemicals we emit that dictate their preference of who to bite.  L-lactic acid, ammonia, carboxylic acids and octenol, especially in combination with each other, are the chemicals most likely to attract them.

Scientist have found that adding l-lactic acid to the scent of someone who is not normally bitten by mosquitoes will make them more attractive to certain kinds of mosquitoes, Richardson reports. The presence of carbon dioxide has also been found in studies to be attractive to certain mosquitoes. Ammonia, which occurs from a pH change when bacteria in sweat multiply, is also appealing to mosquitoes.

So are smelly feet. Studies with Limburger cheese, which resembles human foot odor, have confirmed this. However, malarial mosquitoes are most attracted to this odor, so the saying that "If you keep your feet clean then mosquitoes won't bite," is good advice only if you are traveling in the tropics, Richardson writes.

Human odor that attracts mosquitoes may be genetically driven, but theories vary. One says individuals who are not attractive to mosquitoes don't produce the odors that attract them; and another says some people actually emit an inherited odor that keeps mosquitoes from finding them.

For those who consider themselves "mosquito bait," Richardson makes several suggestions: bathe at dusk, when mosquitoes come out, to minimize sweat odor, rub your body with antimicrobial plants like sage, wear a full-body mosquito net suit or use a repellent, which is the most convenienct, effective protection.

The most common repellent is DEET, available over the counter in many preparations. A prescription repellent is permethrin, which Richardson says may be carcinogenic though it is approved by the Environmental Protection Agency.

A young jewelweed plant

Many people use essential plant oils, though they evaporate quickly, requiring frequent application. The one most commonly recommended is lemon eucalyptus oil, which has proven effective. Richardson's article has details about other plant oils, and recommends crushed jewelweed as a remedy for mosquito bites.

Darla Carter of The Courier-Journal also had a good roundup of mosquito information in the Louisville paper's July 18 edition: http://www.courier-journal.com/story/life/wellness/health/2014/07/17/guard-mosquitoes-summer/12786213/.

First Kentuckian gets Caribbean virus, chikungunya or CHIK-V

State officials have confirmed Kentucky's first case of the Caribbean virus chikungunya—or CHIK-V. The first case is an Anderson County man who recently went to Haiti. Though CHIK-V is not native to Kentucky and doesn't usually result in death, officials encourage those who have recently visited the Caribbean and who may be experiencing symptoms to visit the doctor to make sure they don't have the disease, Josh James reports for WUKY-FM.

The mosquito-borne disease occurs most often in Africa, East Asia and the Caribbean islands, but the federal Centers for Disease Control has been observing the spread of the virus hoping that it won't become a significant issue in the United States like the West Nile did more than 10 years ago, Val Willingham reports for CNN. Several weeks ago, the number of cases in the Caribbean exceeded 170,000, and the number of deaths from the disease was 14, Lisa Schnirring reports for Center for Infectious Disease Research and Policy. 

The disease can cause joint pain and arthritis-like symptoms, and those with weak immune systems are especially at risk for worse symptoms. The disease is transmitted from mosquito to human and from human to mosquito. Though about 25 to 28 travelers bring CHIK-V to the U.S. every year, "We haven't had any locally transmitted cases in the U.S. thus far," said Roger Nasci, chief of the CDC's Arboviral Disease Branch in the Division of Vector-Borne Diseases.

"Someone would have to be bitten by an infected insect to become ill. Person to person contact does not spread the disease," Kevin Hall of the Lexington-Fayette County Health Department said, James writes. However, it's worth noting that Kentucky is "home to both species of mosquito known to carry the virus," James reports.

Laurel County man talks about bout with West Nile; one of few diagnosed with disease in Kentucky

A Laurel County man has shared his story after contracting the West Nile Virus, which, though rare in Kentucky, has been more common nationwide this year than it has been since it was first discovered in 1999.

Kelly Curens spent three weeks at the University of Kentucky medical center, much of which was spent in an induced coma. He started feeling sick after a camping trip at Lake Cumberland, reports Phil Penderton for WKYT-TV. The illness started with a headache and graduated to feeling dizzy, which were symptoms to similar to ones he experienced a few years ago when he was diagnosed with a brain tumor. When he went to the emergency room at St. Joseph London hospital, he had a seizure. 

Curens was one of the first in Kentucky to be positively diagnosed with the virus, which has affected more than 1,100 people nationwide this year. About half of the cases have been in Texas. Four horses have been diagnosed with the disease in Kentucky since Aug. 2. Craig Carter, director of the UK Veterminary Diagnostic Lab, said Kentucky is "still in the high-risk part of the season for West Nile infection."

Curens has been treated and is feeling much better now. "From what I was told, I'm very lucky," he said. "My blood sugar and blood pressure has always been good. Had I not been healthy I probably wouldn't be here today."

The elderly, infants and babies at the most risk, said Marion Pennington, regional epidemiologist at the Cumberland Valley District Health Department.

To protect oneself from the West Nile Virus, officials advise to:
• Dispose of tin cans, plastic containers, ceramic pots and other containers that could collect water.
• Remove discarded tires from properties. They are the most common mosquito breeding grounds in the country.
• Drill holes in recycling containers.
• Drain gutters properly and clean gutters in the spring and fall.
• Turn over swimming pools and wheelbarrows when they aren't in use.
• Change the water in birdbaths on a regular basis.
• Clean and chlorinate swimming pools and hot tubs.
• Make sure screens on windows don't have holes in them.
• Wear long-sleeve shirts and long pants when outside in the early morning and late evening. (Read more)

West Nile outbreak light in Ky. but 'one of the largest' in nation

U.S. health officials reported Wednesday three times the usual number of West Nile cases for this time of year and one expert told the Associated Press it was “one of the largest” outbreaks since the virus appeared in this country in 1999.

So far, 1,118 illnesses have been reported, about half of them in Texas, according to the Centers for Disease Control and Prevention. Kentucky has reported few cases.

In an average year, fewer than 300 cases are reported by mid-August. There have also been 41 deaths this year. Most infections are usually reported in August and September, so it’s too early to say how bad this year will end up, CDC officials said. AP reports that West Nile virus peaked in 2002 and 2003, when severe illnesses reached nearly 3,000 and deaths surpassed 260.

 The best way to prevent West Nile disease, say experts, is to avoid mosquito bites. Insect repellents, screens on doors and windows and wearing long sleeves and pants are some of the recommended strategies. Also, empty standing water from buckets, kiddie pools and other places to discourage breeding. (Read more)

Many more serious cases of West Nile virus reported this year, but only one in Kentucky

Though only one Kentuckian has been affected, more serious cases of people infected by the West Nile virus have been reported this year than any since 2004. Through July, 241 cases were reported in 22 states. The virus has caused four deaths. Nearly 150 cases have been in Texas, particularly in the Dallas area, reports Mike Stobbe for The Associated Press.

Of the 241 cases, 144 were considered serious, meaning the virus spread to the brain and nervous system, causing, among other ailments, encephalitis. Last year, less than 700 cases were reported.
Health officials blame the combination of a mild winter, early spring and hot summer, prime conditions for mosquitoes to breed. "Unless the weather changes dramatically, we'll see more cases (in 2012) than we have in the last couple of years," said Roger Nasci of the Centers for Disease Control and Prevention.

About 1 in 5 people who are infected with the virus get sick. One in 150 get severe symptoms, including neck stiffness, disorientation, coma and paralysis, Stobbe reports. (Read more)

EPA says DEET is safe for fighting off skeeters when used correctly; some natural alternatives are also effective

Though April showers did bring May flowers, May's seemingly constant rain also grew something else in Kentucky: mosquitoes — and lots of them. To protect oneself from the irritating suckers (Getty Images), there is a host of products from which to choose.

The most obvious are products containing DEET, a synthetic compound that was approved for the general public in 1957, reports Amanda Leigh Mascarelli of the Los Angeles Times. DEET is used by 30 percent of Americans each year, the Environmental Protection Agency reports. A 2009 market survey showed products containing the compound accounted for 90 percent of the insect repellent market.

(LAT photo Kirk McKoy) Though popular, DEET has its drawbacks. It can dissolve some plastics, such as soldier's goggles, watchbands and computer keyboards. It can pollute soil and water, is sticky on skin, is not effective against all insects, and is smelly. Is it unsafe? That is a common conception, but EPA insists it is safe when used properly. "There really is no chemical out there that works better than DEET," said Donald Roberts, a retired professor of tropical public health at the Uniformed Services University of the Health Sciences. (Read more)

There are more natural alternatives on the market. Oil of lemon eucalyptus (LA Times photo by Hatley Mason), which is sold under the name Citriodiol, has been proven effective for six or more hours and is found in brands like Repel, Cutter and Coleman Botanicals. Though more natural than DEET, it is still considered a hybrid natural/synthetic product.

A pine oil derivative called isolongifolenone also shows great promise, though testing is still ongoing. "It does look as if this organic repellent functions pretty much at an equal level with DEET, maybe even better," Roberts said. "Until we have a lot more test data, it would be hard to give a definitive statement on that, but I would say that it shows real promise." It is hoped the product will be on the market within 18 months.

Unlike compounds such as DEET, natural repellents are characterized as "minimum-risk pesticides" by EPA, making them "exempt from safety testing because their active and inert ingredients have been deemed safe for intended use," Mascarelli reports. But the manufacturers do not have to prove how well these natural repellents work. For the most part, they do work, but generally not for very long. The lemon-eucalyptus and pine oil alternatives seem to be the exception. (Read more)

Fight is on against mosquitoes, West Nile virus after flooding

The fight is on to rid Western Kentucky of a mosquito infestation  worsened by recent flooding. Treatment to kill adult mosquitoes began Wednesday night, The Gleaner of Henderson reports.

The effort is partly to prevent the spread of the West Nile virus, a potentially serious illness. Mild infection can result in fever, headache, body ache and a skin rash. Severe infection, which affects about 1 in 150 infected people, can lead to high fever, disorientation, sleepiness and even coma, paralysis and death. Mosquitoes can transmit the infection to humans with a bite. (Centers for Disease Control and Prevention diagram)

The state's plan is a two-part process, killing adult mosquitoes and their larvae. It uses aerial spraying over 700,000 acres in Western Kentucky, concentrating on areas along or near waterways where flooding was most problematic. Planes will spray from dusk until after midnight until treatment is complete. Afterward, ground crews with the Transportation Cabinet will treat against mosquito larvae in standing water. The state Department of Agriculture will also spray ditch lines along roads. Chemicals used in the treatments are only harmful to mosquitoes, gnats and black flies, a state press release reads. It is safe for humans, pets and livestock.

Residents are asked to eliminate standing water in containers on their property and wear insect repellent and long-sleeved clothing. (Read more)