City Expert Says Media Distort
West Nile Virus Threat

SAN FRANCISCO -- Carole Toebe is well aware of the dangers associated with the West Nile Virus. The Oxford-born professor of microbiology at San Francisco City College has been tracking the disease since it first emerged in the Western Hemisphere in 1999.

But Toebe isn't panicking. West Nile hasn't even come close to reaching the epidemic treatment she believes the news media have given the virus.

"Everybody thinks, 'I'm going to get encephalitis!'" Toebe said during a Friday lecture about the virus at SFCC's campus. Encephalitis, or viral infection of the brain, is a potentially fatal consequence of the West Nile Virus, and has caused the deaths of 160 Americans so far this year.

Toebe said that compared to the 67,000 Americans who died of the flu or pneumonia in 2000, West Nile seems relatively tame.

"One-hundred sixty versus 67,000 is a big difference," Toebe said. And true, only two cases of West Nile have turned up in California. But that doesn't mean people shouldn't be careful.

Like its countless foreign-born predecessors, the West Nile Virus came to America via New York City, which documented its first-ever case of the virus in 1999, according to the Center for Disease Control. Originally contained in the New York region, the virus spread rapidly through contact with common mosquitoes, and within a year the virus was reported up and down the eastern seaboard.

The CDC soon determined infected mosquitoes had passed the virus to crows and blue jays, two birds most susceptible to the West Nile Virus. When the birds migrated, they brought the West Nile with them.

At first, the virus spread quietly, primarily because most people who become infected show no symptoms. "You didn't see more serious outbreaks in earlier cases," Toebe said. "You mainly had flu-like symptoms."

By September 1999, however, West Nile was well documented in New York. By the end of the month, the greater metropolitan region had reported 37 infections and four fatalities linked to the virus.

Deaths related to the West Nile Virus soon escalated, largely because the disease is so difficult to detect. In 1999 and 2000, 11 percent of West Nile cases resulted in fatality. By 2001, the number had increased to 14 percent.

The outbreak of West Nile left doctors scrambling to come up with an easy screening test for the virus, a search that continues to this day. "You have to use other screening methods that aren't so optimal," said Toebe. The most common method involves an extensive laboratory screening that measures the virus against anti-bodies in the blood. Similarly, no vaccines exist.

Toebe said eliminating environments in which mosquitoes typically breed -- areas that collect shallow pools of water -- is the single biggest means of combating the West Nile Virus. She also recommended using insect repellant when traveling through areas where mosquitoes are commonly found. A 2002 report by The New England Journal of Medicine found the insect repellant DEET to be the most effective and longest lasting repellant, keeping the bugs at bay for 5 to 12 hours at a time.

"The mosquito is the number one killer animal in the world," Toebe said. To emphasize her point, she wore a pair of mosquito earrings, as well as a shirt with a giant mosquito standing over a slogan that read, "Got Blood?"

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