The Department of Health today confirmed 39 new human cases of West Nile virus, marking 215 reported infections of West Nile in Louisiana this year. The State is experiencing its highest number of West Nile cases in several years. There have also been 10 West Nile deaths reported thus far in 2012.

"Hurricane Isaac left behind a lot of water, which, left standing, is a risk for mosquitoes breeding and swarming," said LDH Secretary Bruce D. Greenstein. "In addition to that, fall is getting closer, the weather is getting more pleasant, and people are spending more time outdoors. Everyone needs to be aware of the threat of West Nile virus and Fight the Bite. Put on repellant before you go outside, dress appropriately and empty standing water around your home. Take these small steps to protect your health."

Humans contract West Nile when they are bitten by mosquitoes infected with the virus. When people are infected with West Nile, the virus will affect them one of three ways. West Nile neuroinvasive disease is the most serious type, infecting the brain and spinal cord. Neuroinvasive disease can lead to death, paralysis and brain damage. The milder viral infection is West Nile Fever, in which people experience flu-like symptoms.  The majority of people who contract West Nile will be asymptomatic, which means they show no symptoms. These cases are typically detected through blood donations or in the course of other routine medical tests.

There are 11 neuroinvasive disease cases reported this week, from Caddo (1), East Baton Rouge (2), Jefferson (1), Livingston (3), Lincoln (1), Richland (1), St. Tammany (1) and Tangipahoa (1) parishes. Ten of these cases are newly reported West Nile infections, and one is a previously diagnosed case that progressed into neuroinvasive disease.

There are 28 new West Nile Fever cases, from Ascension (1), Caddo (1), Calcasieu (1), Concordia (1), DeSoto (1), East Baton Rouge (5), Iberville (2), Jefferson (1), Lafourche (1), Lafayette (1), Livingston (1), Orleans (1), Ouachita (1), Pointe Coupee (3), St. Charles (1), St. Tammany (3), Tangipahoa (1), Washington (1) and West Baton Rouge (1) parishes.

One of the 39 new cases is asymptomatic, from Calcasieu Parish.

LDH issues a weekly Arbovirus Surveillance Report that details cases detected thus far by parish, which is published here.

The most active year for West Nile cases in Louisiana was 2002, when the state experienced 328 cases and 24 deaths. For 10 years, state health officials have conducted robust surveillance year-round, which includes working with doctors, hospitals and health care providers around the state to track human cases and reminding people to be vigilant in avoiding mosquito bites.

"A decade of surveillance has shown us that this virus is active in every part of our State, meaning everyone is at risk," Greenstein said. "We know older people and those with weakened immune systems are most at risk for neuroinvasive disease, but if you can be bitten by a mosquito, you can get West Nile virus. Own your own health, and take steps to protect yourself and your family."

Fight the Bite

Local mosquito control partners and abatement districts remain vigilant in keeping the population of infected mosquitos under control, but everyone has a personal responsibility to avoid mosquito bites. Health officials recommend:

  • If you will be outside, you should wear a mosquito repellent containing DEET. The American Academy of Pediatrics (AAP) recommends that repellents should contain no more than 30% DEET when used on children. Insect repellents also are not recommended for children younger than 2 months. CDC recommends that you always follow the recommendations appearing on the product label when using repellent.
  • People should be especially vigilant if they are outside at dawn and dusk. The mosquitoes that carry West Nile are most active at that time. But, people should take precautions against mosquitoes if they are outside at any time of day.
  • Apply repellent on exposed skin and clothing. Do not apply under your clothes or on broken skin.
  • To apply repellent to your face, spray on your hands and then rub on your face.
  • Adults should always apply repellent to children.
  • Wear long-sleeved shirts and pants when outdoors for long periods of time.
  • Avoid perfumes and colognes when outdoors for extended periods of time.
  • Make sure that your house has tight-fitting windows and doors, and that all screens are free of holes.

Another effective way to prevent mosquito bites is to drain stagnant water from around homes and property to prevent mosquitoes from breeding and swarming:

  • Dispose of tin cans, ceramic pots and other unnecessary containers that have accumulated on your property. Turn over wheelbarrows, plastic wading pools or buckets that could collect water.
  • Drill holes in the bottom of outdoor recycling containers. Drainage holes that are located on the container sides collect enough water for mosquitoes to breed.
  • Clean clogged roof gutters yearly. They are often overlooked, but can produce millions of mosquitoes each season.
  • Aerate ornamental pools or stock them with fish. Water gardens can become major mosquito producers if they are allowed to stagnate.
  • Clean and chlorinate swimming pools that are not being used. An unattended swimming pool can produce enough mosquitoes to result in neighborhood-wide complaints. Be aware that mosquitoes may even breed in the water that collects on swimming pool covers.

For more information on West Nile activity in Louisiana and prevention tips, visit