Mosquitoes bring fears of West Nile Virus

By  Amber James | gargoyle@flagler.edu
Graphic by Victoria Van Arnam

A black curtain. That is what Rachael Horn says the mosquitoes in her St. Augustine yard are like.

Florida spends about $160 million on mosquito control, and mosquitoes in the state are a fact of life. The fine arts major knows it.

“I brave the mosquitoes to go outside,” Horn said.

Just north of St Augustine in Duval County, 11 people have been infected with West Nile Virus. But that hasn’t stopped Horn, originally from Fort Myers, from enjoying the outdoors. So is West Nile Virus, contracted by humans and animals every year, really a cause for panic?

The Local Picture

Out of the 11 confirmed cases of West Nile Virus in Duval County, two of the most recent cases were screened for West Nile Virus when trying to donate blood and confirmed infected.

Last month, a 64-year-old Westside women infected with West Nile Virus died, though she did have preexisting health conditions.

“Most people recover but those who are most at risk for developing difficulties are those who are older and those who already have chronic diseases that weaken the immune system,” Judy Angyalfy, a nurse at Flagler College, said.

There have been no reported cases in St Johns County of West Nile Virus or other mosquito-borne illnesses, but Anastasia Mosquito Control has increased fogging. “We’re trying to knock down the population low,” Rui-De Xue, the director of Anastasia Mosquito Control, said.

But with the rainy season continuing in September, mosquitoes will still be a strong presence. “It looks we will have more rain and mosquitoes in September and October.

The population of salt marsh mosquitoes has also been increasing in the Ponte Vedra Beach area. Salt marsh mosquito population depends on tide regularity and Guana lake river water discharge,”Xue said. “Sometimes, the water discharge increases or decreases the breeding sites for salt water mosquitoes.”

The National Picture

Florida has the fourth most confirmed cases of West Nile Virus in 2011, all from Duval County, according to the most recent data from the Center of Disease Control.

Arizona has the most with 16 positive test results, followed by Mississippi with 15 and California with 12 positive test results. 20 states in 2011 have had positive tests so far.

Nationwide, only three cases have been fatal occurring in Florida, Mississippi and Texas. Last year there were 1,021 total cases with 57 being fatal. A total of 12 cases were reported in Florida.

This data reflects the local jurisdiction of residence and not necessarily the locale where the infection was acquired.

West Nile Virus

First identified in 1937 in Uganda and first discovered in the United States in the summer of 1999 in New York, West Nile Virus is passed from the bite of a mosquito. Mosquitoes become infected when they feed on infected birds.

There is no vaccine for West Nile Virus. Mosquitoes carry the highest amounts of the virus in the early fall, which is why the rate of the disease increases in late August to early September and decreases when the weather becomes colder as mosquitoes die off.

About 1 in 150 people infected with WNV will develop severe illness with symptoms including high fever, neck stiffness, disorientation, convulsions, muscle weakness, vision loss, and numbness among others.

Prevention

“Drain and Cover” is one way to remember how to prevent mosquito bites and growth. Eliminate standing water such as puddles in boats or the trays under potted plants where mosquitoes can lay eggs.

Wear long sleeves and pants when weather permits to protect against bites as well as wearing mosquito spray. The time from dusk to dawn are peak biting times for mosquitoes so try and stay inside at those times.

Reporting dead birds to local authorities can also help authorities determine if there is West Nile Virus being spread between birds and mosquitoes. Over 130 species of birds are known to have been infected with West Nile virus, though not all infected birds will die.