By Cheryl Millham

Since West Nile Virus (WNV) has been reported with two American Robins in the Tahoe Keys area, many people are all of a sudden interested in learning more about this disease.

So, “What is West Nile Virus and Where did it come from?”

WNV is a mosquito borne virus that has been found in parts of Asia, Eastern Europe, Africa and the Middle East. The virus was first detected in the United States in New York City in 1999. WNV had its first active case in California in 2002, taking almost four years to cross the country.

I received a bulletin update from the California Department of Public Health on April 25, 2012. It read: “To date, there have been 3,146 human cases in California and 110 deaths. Last year (2011) 2,497 birds were tested, of which 28 percent were WNV positive. In addition, 108 dead tree squirrels were tested and 22 percent were positive. Dead bird surveillance is a key component of our early warning system, because positive birds are typically the first indicators of WNV in a county. Tree squirrels are also indicators of WNV in a local area.”

WNV is transmitted to people and animals by infected mosquito bites. The good news is that only certain species of mosquitoes carry the virus. A mosquito first acquires the infection by feeding on a bird with the virus in its blood. The virus lives in the mosquito and is transmitted to a new host in the mosquito’s saliva when the insect bites a person or animal. Human to human, bird or animal to human transmission of WNV does not occur.

So, please, if a bird or animal needs your help, help it. You cannot contract WNV from them, only by the bite of the mosquito.

Most people who are infected with WNV have no symptoms, whatsoever. The incubation period (the time between the bite and the onset of illness) range is five–15 days. Symptoms can include fever, headache, nausea, body aches, mild skin rash or swollen lymph nodes. One in every 150 people who are infected with WNV will require hospitalization.

So, what do you do if you find a dead bird or squirrel??

Get a plastic bag and reverse it. Put your hand inside the bag and pick up the dead bird or animal. Pull the plastic bag over the dead bird, then, call the WNV hotline, 877.968.2473. It is a toll free call and, if they want the dead bird or animal, they will arrange for a pick up. If they do not want it, just dispose of it in your trash.

What can we do to limit mosquito bites?

When you are outside, in the early morning and evening, be sure you have mosquito repellent on exposed skin. Be certain window screens are tight fitting and in good repair (remember, screens keep out mosquitoes, but are nothing to a bear). Buy mosquito fish for your ponds and keep your water moving. Mosquitoes don’t lay eggs in moving water.

The best part is to let our local birds help out. All swallows can eat up to 1,000 mosquitoes per day.

Ducks eat mosquito larvae as do frogs and snakes.

But, the best of all are bats. Bats can eat up to 1,000 mosquitoes per hour in a feeding frenzy. Here, at Lake Tahoe, we have only insect eating bats. So, don’t harm them. But encourage them by putting up bat houses.

My facts for this article were taken from the California Surveillance and Facts about WNV.

Cheryl Millham is executive director of Lake Tahoe Wildlife Care on the outskirts of South Lake Tahoe.