Attention Turns To Repelling Mosquitoes That Carry Zika, Dengue The WHO says the possible link between serious birth defects and the Zika virus is a global health emergency. Renee Montagne talks to Laura Harrington, an entomologist at Cornell University.

Attention Turns To Repelling Mosquitoes That Carry Zika, Dengue

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The World Health Organization has deemed the possible link between serious birth defects and the Zika virus as an international health emergency. As we all know now, the virus is spread by mosquitoes. Laura Harrington is an entomologist at Cornell University. She's an expert on mosquitoes and expects to see cases from people being bitten by those carrying the Zika virus right here in the U.S.

LAURA HARRINGTON: Well, I think this spring as the mosquito populations start to increase, we should be especially cautious about locations where we've had locally-transmitted Dengue virus. The same mosquito species that transmits Zika also transmits Dengue. It's confined primarily to Florida, South Florida, along the Gulf states and Southern Texas with a few small populations in Arizona and California.

MONTAGNE: Does that really mean that that's where it will stay, this particular mosquito and this particular disease?

HARRINGTON: Not necessarily. Not a lot of attention has been paid to the Asian tiger mosquito, which is another species which we believe can also transmit Zika virus. It has a much broader range. It's found all the way north into coastal areas of Connecticut, Long Island and the New York metro area.

MONTAGNE: What about things that individuals can do like keeping standing water out of the yard or wear repellant or long sleeves or long pants at dusk and dawn when mosquitoes tend to appear?

HARRINGTON: Well, it's very, very important that people realize that both species are day-active mosquitoes. And so people are at greatest risk during the day. That being said, repellents are probably the best line of defense right now. People can try to find breeding sites for these mosquitoes. However, I can tell you, the larvae can develop in a teaspoon of water.

MONTAGNE: Well, what can communities do or even, you know, counties or states?

HARRINGTON: Well, you know, they can talk to people about source reduction or removing breeding sites. And where there are active mosquito control programs, they can spray. However, if you're spraying for adult mosquitoes, it can be very difficult to get into the little nooks and crannies where they're resting and actually come in direct contact with the mosquitoes.

MONTAGNE: Some people are talking about proposing that the ban on the pesticide DDT be dropped. What do you think of that idea?

HARRINGTON: Well, you know, I think that DDT holds a lot of promise. It hasn't been banned everywhere - obviously it has in the U.S. In fact, about 10 years ago, the WHO came out with a statement promoting it for public health interventions in many countries. It's cheap. It's very, very effective. We've never had an insecticide that has worked so well since. It's also safe. A lot of people don't realize that its toxicity profile for humans is low. The drawbacks are, of course, that it can cause tremendous environmental devastation through biomagnification. You have to balance the pros and cons. And I think each country needs to do that for themselves.

MONTAGNE: Well, thank you very much for joining us.

HARRINGTON: Thank you.

MONTAGNE: Laura Harrington is an entomologist and an expert on the Zika virus at Cornell University.

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