West Nile virus found in squirrel

(San Mateo Daily Journal) Local mosquito experts confirmed a squirrel collected earlier this month in the city of San Mateo was positive for the West Nile virus which in itself isn’t dangerous for humans but implies the presence of infected mosquitoes.That implication is leading health officials to urge people to take precautions against the potentially fatal virus, such as wearing mosquito repellent and removing standing water from property. “[T]he presence of infected squirrels means that there likely are infected mosquitoes nearby, which increases the chances that human cases may appear in San Mateo County. We urge residents to take steps now to protect themselves from mosquito bites,” Dr. Alvaro Garza, San Mateo County deputy health officer, wrote in an announcement of the squirrel discovery.

Mystech: You know you’re dealing with a ruthless foe when they’ll infect their own kind (or selves) just to serve as weapons against humans.  If a squirrel ever sneezes in your presence, never say “Bless You”, because its probably intentional. 

On July 9, the San Mateo County Mosquito Abatement District collected an eastern grey squirrel in San Mateo, said health spokeswoman Beverly Thames.

The animal was sent to the University of California at Davis Center for Vectorborne Diseases which confirmed the presence of West Nile.

West Nile is typically spread by mosquito bites to other animals. After birds, especially crows, the virus tends to infect squirrels, Garza said.

The squirrel is the first sign of West Nile virus in San Mateo County during 2007. The county, which has detected the virus since 2004, is one of 32 counties statewide with confirmed presence. So far, human cases have appeared in court counties and Kern County reported one death.

Last year, there were a total of 278 cases in California and seven deaths from the disease but no human cases in San Mateo County, Thames said.

As of last year, the Centers for Disease Control and Prevention estimated West Nile infected 1.2 million to 1.3 million people in the United States in the seven years since its presence was first identified in the nation.

However, only approximately one in five people develop symptoms and even fewer develop the life-threatening disease that has claimed 800 people and left more than 8,000 with neurological illness, meningitis or encephalitis.

To reduce the risk, the mosquito abatement district suggests draining standing water weekly, taking precautions during dusk and dawn, using insect repellents with the ingredient DEET, dressing in long sleeves and pants when mosquitoes are active and replacing damaged or missing screens on windows and doors.