Two patients were hospitalized and are recovering. Three healthy blood donors were found to be infected with West Nile Virus (WNV), though they have remained healthy. The individuals are from wide-ranging areas of Los Angeles County, the department said.
In 2012, 174 cases were reported in L.A. County, the second highest count since 2004. Four percent of the 2012 cases were fatal; 85 percent of those infected required hospitalization.
As of July 19, 2013, WNV has been detected in 89 mosquito pools and 93 dead birds in Los Angeles County, the department said. Seventy-five percent of dead birds and nearly one-third of mosquitoes were found in the South Bay, but WNV activity has been found in other areas across Los Angeles County.
The Orange County Health Care Agency said there are no confirmed cases of WNV in humans this year. Four birds were confirmed to have West Nile Virus this year.
In Los Angeles County, dead birds may be reported by calling (877) 968-2473 or logging onto L.A. County Veterinary Public Health. Stagnant swimming pools or "green pools" should be reported to the Public Health Environmental Health Bureau at (626) 430-5200, or to a local vector control agency.
West Nile Virus is spread from humans through the bite of an infected mosquito; mosquitoes can become infected by biting a bird that carries the virus. Most mosquitoes do not carry the virus and most people bitten by a mosquito are not exposed to the virus. The virus is not spread through person-to-person contact, or directly from birds to humans.
In most cases, people who are infected with West Nile virus never become sick, or have only very mild symptoms that include fever, headache, nausea, body aches, and a mild skin rash. Symptoms of WNV could appear within three to 12 days after infection. Fewer than one in 150 people who are bitten by an infected mosquito become severely ill, according to the Centers for Disease Control and Prevention (CDC). In these rare cases, the virus can cause encephalitis and death. The elderly and those with weakened immune systems are most at risk for developing severe symptoms, which may require hospitalization. Recovery from any infection with the virus can take months to years and include symptoms of fatigue, malaise, and depression. There is no specific treatment for this disease.
Decrease risk of infection:
- Avoid mosquito-infested areas at dawn and dusk.
- Wear long-sleeved shirts and long pants whenever you are outdoors.
- Repellants containing DEET, picaridin, or oil of eucalyptus, when used as labeled, are effective defenses against mosquitoes.
- Check your window screens for holes.
- Do not allow water to collect and stagnate in old tires, flowerpots, swimming pools, birdbaths, pet bowls, or other containers. These are prime breeding grounds for mosquitoes.
- Clean and chlorinate swimming pools; drain water from pool covers.
- Stock garden ponds with goldfish or other mosquito-eating fish. These eat mosquito eggs and larvae.
- Empty and wash birdbaths and wading pools weekly.
- Information on West Nile Virus by phone: (800) 975-4448.
- Information on West Nile Virus on the web: California West Nile Virus Website
Where to call with questions about mosquitoes:
Greater Los Angeles County Vector Control District: (562) 944-9656
Los Angeles County West Vector Control District: (310) 915-7370
San Gabriel Valley Mosquito and Vector Control District: (626) 814-9466
Antelope Valley Mosquito and Vector Control District: (661) 942-2917
Compton Creek Mosquito Abatement District: (310) 933-5321
Pasadena City Health Department: (626) 744-6004
City of Long Beach Vector Control Program: (562) 570-4132
The Los Angeles County Dept. of Public Health provided resources for this report.