- The Washington Times - Sunday, February 14, 2016

They bite during the day and find humans tastier than the rest of the animal kingdom — and that’s exactly what makes the Aedes mosquito so dangerous.

Well, that and the fact that it carries the Zika virus, which has terrified the globe.

“There is the enemy,” Dr. Tom Frieden, chief of the Centers for Disease Control and Prevention, told Congress as he projected an image of the bug on screen last week, calling for a massive effort — with a staggering $1.8 billion price tag — to combat the danger.

The Zika virus is an obscure agent that festered in Africa and the Asia-Pacific region for decades before it made its way to Brazil by early 2015. Since then, it has been linked to a major uptick in microcephaly, a condition in which babies are born with abnormally small heads — raising the stakes around a virus that otherwise typically causes mild symptoms and more often none at all.

It also means the Aedes aegypti mosquito is now a primary foe in at least 25 Latin American countries.

The U.S. is bracing for a fight of its own, once temperatures climb and mosquitoes proliferate. Aedes aegypti populations tend to be limited to a few Southern states, such as Florida and Texas, and many American homes and businesses employ air conditioning or have screened-in windows, forcing the mosquitoes outside.

Scientists say the species thrives on coasts and could expand its northern reach in the summertime.

Another mosquito, the Aedes albopictus, is more prevalent in the U.S. and has spread Zika in a laboratory setting.

Whether that poses a problem will be become clear in the next few months as Zika pushes north and threatens U.S. shores, said Grayson Brown, a professor of entomology at the University of Kentucky. Mr. Brown said the albopictus is also native to such islands as Puerto Rico and the Virgin Islands.

“If albopictus is going to drive an outbreak, we’ll see it on those Caribbean islands” first, he said.

For now, it is the aegypti form that is upending federal budgets, travel plans and Rio de Janeiro’s hopes of hosting a successful Olympics in August.

Lurking in closets and other tight spaces, the wily perpetrators strike at any time of day. Brazil is so fed up that it has declared “war” on the bugs, plastering their likeness everywhere — like “Most Wanted” posters.

Entomologists describe the Aedes aegypti as a highly adaptable menace, shrugging off adverse conditions such as drought while hatching their young in ad hoc delivery rooms — tin cans, birdbaths, tree holes, old tires, flower pots and so on.

“It can breed in a bottle cap,” said Jason Rasgon, associate professor of disease epidemiology at Pennsylvania State University.

Scientists say an old-school version of the mosquito lives in tree holes such as those in the Zika Forest of Uganda — the virus’ namesake. It has a relatively balanced diet, unlike a domestic version that has developed an affinity for human flesh and tends to makes itself at home among humans instead of flying away.

That ability to thrive in human residences limits the ability to wipe out populations with sprays, much less toxic compounds such as DDT.

“In many ways, it’s an ideal urban mosquito,” said Michael Kaufman, associate professor of entomology at Michigan State University.

A number of triggers attract the mosquitoes to humans, including the carbon dioxide we breathe, body heat and certain compounds in human odors.

The females, which do the biting, use blood to nurture their eggs. But the aegypti mosquitoes plaguing Latin America also use blood as a source of nutrition — there isn’t enough sugar around to sustain themselves — so they tend to feed more often.

“It will sometimes bite four humans in one feeding, and therefore it spreads the disease quickly,” Health and Human Services Secretary Sylvia Mathews Burwell told senators last week.

The Obama administration is pleading with Congress to authorize Mr. Obama’s request for emergency funds, saying the Zika threat requires a multipronged approach, including development of a vaccine and vector control.

Scientists say Aedes populations can be managed as long as everyone in a given community is committed to the fight.

“You have to make it socially unacceptable to have mosquitoes, the way you make it socially unacceptable to drive drunk,” Dr. Brown said.

Hoping to set the right tone, the Brazilian Health Ministry moved last month to knock out standing water in federal buildings across the country, saying “a mosquito is no stronger than a whole country.”

For now, U.S. officials have urged pregnant women to defer travel to countries where the virus is spreading. Officials advise those who must go to such areas to wear long sleeves, apply insect repellent and take other measures to protect themselves from mosquito bites.

Entomologists say Zika certainly isn’t the first mosquito-borne illness to plague humans — the same insects carry yellow fever, dengue and chikungunya — and it won’t be the last. Although the fight may be tense, there is no reason to take it personally.

“Mosquitoes are just trying to make a living,” Mr. Rasgon said. “They’re not trying to kill us.”

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