Napa County Public Health Division and Napa County Mosquito Abatement
District confirmed this week that a 65-year-old man has become the first
person to test positive for West Nile virus in Napa County this year.
The man developed WNV meningitis and was admitted to the hospital. He has since fully recovered and has returned home.
In addition to the first human case, the California Department of Public Health confirmed the first dead bird positive for WNV on Aug. 19. The bird was a Western Scrub Jay collected in the Calistoga area on Aug. 9.
"This first dead bird testing positive for West Nile Virus and the first human case reminds us that we must take precautions to protect ourselves and our families from mosquito bites," said Dr. Karen Smith, Napa County public health officer. "West Nile virus activity is greatest during the summer, when we are outside enjoying the weather."
WNV is transmitted to humans and animals by the bite of an infected mosquito. The risk of serious illness to most people is low. Napa County Public Health recommends that people prevent exposure to mosquito bites and WNV by practicing the "Three Ds":
- Apply insect repellent containing
DEET, picaradin, oil of lemon eucalyptus or IR3535 according to label
instructions. Repellents keep the mosquitoes from biting you. DEET can
be used safely on infants and children 2 months of age and older.
2. DAWN AND DUSK
- Mosquitoes bite in the early morning and evening
so it is important to wear proper clothing and repellent if outside
during these times. Make sure that your doors and windows have
tight-fitting screens to keep out mosquitoes. Repair or replace screens
with tears or holes.
3. DRAIN - Mosquitoes lay their eggs on standing water. Eliminate all sources of standing water on your property, including flower pots, old car tires, rain gutters and pet bowls. . If you know of a swimming pool that is not being properly maintained or for other mosquito problems contact the Napa County Mosquito Abatement District at (707) 553-9610.
• Serious symptoms in a few people: Less than one percent of individuals (about 1 in 150 people) infected with WNV will develop severe illness. The severe symptoms can include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis. These symptoms may last several weeks, and neurological effects may be permanent. WNV infection can be fatal.
• Milder symptoms in some people: Up to 20 percent of the people (about 1 in 5) who become infected will display symptoms which can include fever, headache, body aches, nausea, vomiting, and sometimes swollen lymph glands or a skin rash on the chest, stomach and back. Symptoms generally last for just a few days, although even previously healthy people have been sick for several weeks.
• No symptoms in most people: Approximately 80 percent of people (about 4 out of 5) who are infected with WNV will not show any symptoms.
At-risk Groups: People 50 years of age and older have a higher chance of getting sick and are more likely to develop complications. Recent data also indicate that those with diabetes and/or hypertension are at greatest risk for serious illness. Contact your healthcare provider if you think you or someone in your care may have symptoms of WNV.
California's WNV website includes the latest information on WNV activity in the state. Californians are encouraged to report all dead birds and dead tree squirrels on the website or by calling toll-free 1-877-WNV-BIRD (968-2473). Go to http://westnile.ca.gov/ for more information.
For local problems with mosquito control contact the Napa County Mosquito Abatement District at (707) 553-9610.