As summertime approaches, so do the mosquitoes, and with mosquitoes come the inevitable reports of West Nile virus.
That’s because for the past six years, Valley mosquitoes have tested positive for West Nile, a virus with effects that can range from asymptomatic to flu-like to swelling of the brain and even death. But before donning your mosquito netting and locking your doors, keep in mind that West Nile can be avoided.
While the Southern Nevada Health District takes West Nile very seriously, Vivek Raman emphasizes that people shouldn’t overreact.
“When we’re talking about West Nile, it’s important for people to know that it’s a completely preventable disease,” says Raman, an environmental health supervisor with the health district. “You get it though the bite of an infected mosquito. And so by preventing mosquito bites in the first place, you’re protecting yourself from the disease.”
In 2009, there were 12 cases of West Nile in the Las Vegas area. The Centers for Disease Control and Prevention reported 663 confirmed human cases of West Nile in the United States, with 30 deaths reported. To put that in perspective, CDC estimates that more than 200,000 people are hospitalized from flu-related complications each year, with about 36,000 people dying from flu-related causes.
The first case of West Nile in Nevada dates to 2004, when it was detected in a dead crow found in Carson City. The virus can be transmitted from birds to mosquitoes, and from mosquitoes it can affect humans and horses (and to a lesser extent dogs and cats). It is not transmitted through human-to-human contact.
Experts say that because the virus has been found in Las Vegas every year since 2004, it’s here to stay.
“It’s pretty much part of our ecosystem now,” Raman says. “You’ll find spikes and you’ll find decreases of West Nile, I’m sure, for years to come. It depends how much you survey, how much you test. There are a lot of factors that really go into it. But once we have it, it’s here to stay. I’m confident about that.”
The most popular lair for mosquitoes is above and around stagnant swimming pools. Raman says the health district in 2009 responded to 2,500 complaints about stagnant swimming pools, most of which were located on vacant property.
The health district’s Vector Control office also tested nearly 18,000 mosquitoes last year and found West Nile virus in about 250 of them. This year it has started testing the insects, but because of the recent strong winds it hasn’t yet caught a good sample size. Still, the health district has already visited more than 1,000 homes where stagnant water was reported.