Americans are more likely to catch the Zika virus from a trip abroad than a mosquito bite in their backyard, and officials along the threatened Gulf Coast want to keep it that way, drawing up game plans to defend against disease-carrying insects before they spark an outbreak on the mainland.
Louisiana State University’s diagnostics lab is geared up to test mosquito samples from at-risk parishes, while the Florida Keys’ mosquito control board is going door to door with the Navy and Coast Guard to leave door hangers and educate people about Zika, which causes serious birth defects.
The virus is a wily one, in that many people don’t exhibit symptoms. State officials say that shouldn’t be a serious problem, so long as they are vigilant and rely on systems they’ve used to defend against viruses like West Nile and dengue.
“We don’t get frustrated, we just get busy,” said Raoult Ratard, state epidemiologist for Louisiana.
The Centers for Disease Control has recorded nearly 600 travel-related cases of Zika in the states and D.C., a handful of them through sexual transmission. As temperatures climb and insects flourish, scientists fear that Aedes mosquitoes will begin to bite infected travelers and then spread the disease with their next blood meal, sparking the type of local transmission that afflicts Latin American countries, including the U.S. territory of Puerto Rico.
“If you get bitten by this mosquito when you travel someplace where it might be pervasive, you not only get bitten yourself, you bring it home,” House Minority Leader Nancy Pelosi said Friday, imploring Congress to fulfill President Obama’s $1.9 billion request to fight Zika, though Republican leaders are negotiating a smaller amount.
As it stands, the CDC says it cannot predict the extent to which Zika will spread in the continental U.S., though it notes that mosquitoes capable of carrying the virus can be found as far north as Cincinnati, New York City and San Francisco.
States on the Gulf of Mexico are on the front lines of a potential outbreak, because their hot and wet climates attract Zika’s primary vector, the Aedes aegypti mosquito.
Alabama officials said is it “critical” that all health providers are required to report all test results of suspected Zika cases to its Department of Health, so investigators can determine if someone picked up the virus abroad or if local transmission has begun.
Taking their cues from the CDC, states are testing for Zika based on a patient’s travel history and symptoms such as fever, mild rash or joint pain.
“If it’s determined there is actually a Zika case, it’s referred over to me,” said Kyle Moppert, medical entomologist for the Louisiana Department of Health and Hospitals.
If the infected person was likely exposed to local mosquitoes, he should notify local abatement teams so health officials can spray a radius of 150 meters from where that person lives. They will not do anything to single out the affected household, due to health information privacy laws, and will go door-to-door in the community to look for potential mosquito breeding sites.
“Anything that holds water is very important in this case,” Mr. Moppert said.
Aedes aegypti mosquitoes are mainly found in several parishes around Lake Pontchartrain, though another known vector, the Aedes albopictus, is found throughout Louisiana.
The Louisiana Animal Disease Diagnostic Laboratory at LSU tests thousands of mosquito pools — plus chickens, wild birds and horses — for a variety of viruses, from West Nile to chikungunya, and sends reports to mosquito control districts and state and federal officials.
Now, it has added Zika to the list, said Alma Roy, the lab’s assistant director.
“We have not tested any mosquitos for Zika at this time, but stand ready,” she said.
Further east, the Florida Keys is exploring a series of techniques to knock down mosquito populations before they can spread Zika. A plan to release genetically modified mosquitoes that produce unviable offspring has proven controversial, however, and will go before local voters in August.
For now, the Keys will rely on its traditional methods for dealing with mosquitoes, should someone bring the virus back with them. That means a lot of local spraying, including the use of aerial spraying if the virus begins to spread on its own.
Yet so far, the Keys haven’t seen any travel-related cases.
“However, since only one in five who have Zika develop any symptoms,” Mr. Goodman said, “we could have cases and do not know it.”
• Tom Howell Jr. can be reached at thowell@washingtontimes.com.
Please read our comment policy before commenting.