Most people who get infected with the West Nile virus don't even know they are infected. Some will suffer flu-like symptoms. One in 150 or so will develop neuro-invasive disease and experience swelling of the brain, brain lining or spinal cord, which can cause paralysis or death.

The East Baton Rouge Parish Mosquito Abatement and Rodent Control District reported 41 percent of the 156 samples of mosquitoes submitted to the LSU Vet School this week tested positive for West Nile Virus.

The samples were collected between July 12 and July 19 from 28 separate locations throughout the parish.

Two sentinel chickens also tested positive for the bird virus. The chickens are kept in cages to see if infected mosquitoes bite them.

One of the sentinel chickens was from the Blackwater Road area and one from the area of River Road near the Farr Park Horse Activity Center.

Spreading to Other Mosquito Species

The Louisiana Department of Health and Hospitals reported six dead birds that were collected from several different areas of East Baton Rouge Parish between June 20 and July 10 also tested positive for West Nile virus.

Birds act as reservoirs for the virus. Mosquitoes get infected by biting and drawing the blood of birds and can then pass on the virus to people or other mammals.

Most of the mosquitoes testing positive this week were southern house mosquitoes.

"This mosquito bites at night and likes to bite inside homes," said Matt Yates, director of the control agency.

One sample of Asian tiger mosquitoes also tested positive, "and this very aggressive mosquito species bites outdoors during the day." Yates said.

Another mosquito species with no common name also tested positive; it bites outdoors at night.

"So West Nile virus seems to be spreading from wild birds into other mosquito species, and this further increases the potential for human infections," Yates said.

Severe Consequences for 1 in 150

The state has reported only two human cases of West Nile this year, both of them women from Livingston Parish.

Most people who get infected don't even know they are infected. Some will suffer flu-like symptoms. One in 150 or so will develop neuro-invasive disease and experience swelling of the brain, brain lining or spinal cord, which can cause paralysis or death.

Residents should continue to take precautions to eliminate mosquito breeding sources around their homes by dumping containers holding water and protect themselves from mosquito bites when outdoors.

Another mosquito-borne disease, Eastern equine encephalitis, can infect horses and humans, and a case was confirmed in a horse in Livingston Parish earlier this week, Yates said.

West Nile was first reported in the United States in New York in 1999. It was first detected in East Baton Rouge Parish in 2002.

In 2004 there were 30 confirmed human cases of West Nile Virus in East Baton Rouge Parish. Seven cases had dates of onset in July, eleven in August, and six each in September and October 2004.

Yates recommends using repellents that contain DEET, picaridin or lemon eucalyptus oil as the active ingredient.

To report a dead bird to the parish Health Department, call (225) 242-4870, or the control agency at (225) 356-3297.