San Joaquin County Mosquito & Vector Control District is committed to help you and your family from mosquito bites that can spread West Nile Virus. This area deals with: - What Is It? (FAQs) see below - Prevention - Reporting - Task Force.
FAQs
What is West Nile Virus?
West Nile virus (WNV) is a potentially serious mosquito-borne disease commonly found in
Africa, Asia, and the Middle East. It was first detected in the U.S. in
1999 in New York. Since then it has rapidly moved westward and now been
found in all of the continental United States.
How do people get WNV?
Infected Mosquitoes. Most often, WNV is spread by the bite of
an infected mosquito. Mosquitoes are carriers ("vectors") that
become infected when they feed on infected birds. Infected
mosquitoes can then spread WNV to humans and other animals when they
bite.
Transfusions, Transplants, and Mother-to-Child. All donated blood is checked for WNV before being used. The risk of getting WNV through blood transfusions and organ transplants is very small, and should not prevent people who need surgery from having it. Transmission during pregnancy from mother to baby or transmission to an infant via breastfeeding is extremely rare.
Not through touching. WNV is not spread through casual contact such as touching or kissing a person with the virus, or by breathing in the virus.
How soon do infected people get sick?
People typically develop symptoms from 3 to14 days after they are
bitten by an infected mosquito.
What are the symptoms of WNV?
WNV affects the central nervous system. However, symptoms vary:
Who is at greatest risk of getting severely ill from WNV?
People over the age of 50 have a higher chance of getting sick and are more likely to develop serious symptoms when infected with West Nile virus.
Being outside, especially at dawn or at dusk, increases your risk of being bitten by an infected mosquito. Take precautions to avoid mosquito bites if you spend a lot of time outside, either working or playing.
Risk of transmission through medical procedures is very low. All donated blood is checked for West Nile Virus before being used. The risk of getting WNV though blood transfusions and organ transplants is very small, and should not prevent people who need surgery from having it.
How is WNV infection treated?
There is no specific treatment for WNV infection. In cases with
milder symptoms, people experience fever and aches that pass on
their own. In more severe cases, people may need to go to the
hospital where they can receive supportive care including
intravenous fluids, help with breathing, and nursing care.
What should I do if I think I have WNV?
Milder WNV illness improves without treatment, and people do not
necessarily need to seek medical attention for this infection,
though they may choose to do so. If you develop symptoms of severe
WNV illness, such as unusually severe headaches or confusion, seek
medical attention immediately. Pregnant women and nursing mothers
are encouraged to talk to their doctor if they develop symptoms that
could be WNV.
If you have had WNV, are you immune to further
infections?
It is thought that once a person has recovered from WNV, they are
immune for life to future infections with WNV. This immunity may
decrease over time or with health conditions that compromise the
immune system.
Can animals get sick from WNV?
An infected mosquito can bite any animal, but not all animals will
become sick. The disease most often affects birds but may
occasionally cause disease in other animals.
Wild birds serve as the main source of virus for mosquitoes. Infection has been reported in more than 225 bird species. Although many birds that are infected with WNV will not appear ill, WNV infection can cause serious illness and death in some birds. The most severe illnesses are seen among the corvid birds, which include crows, jays, ravens, and magpies.
Squirrels & Rabbits with West Nile virus can develop neurological symptoms such as uncoordinated movement, paralysis, shaking, or circling and may die.
Like people, most horses bitten by mosquitoes will not become sick with WNV. However, of those that do, clinical signs may include stumbling, circling, hind leg weakness, inability to stand, muscle tremors, and death. A vaccine to prevent West Nile virus is available for horses and horse-owners should consult with a veterinarian about vaccinations for WNV and other mosquito-borne viruses, such as western equine encephalomyelitis. For more information on West Nile Virus and horses, please visit the California Department of Food and Agriculture website.
Dogs and cats can be exposed to WNV in the same way as humans. However, these animals are very resistant to WNV and rarely become ill. Concerned pet owners should consult with a veterinarian.
I am a physician, where can I go to obtain more
information?
Health care providers should contact their local public health
department to discuss requirements for testing or visit
http://www.westnile.ca.gov/resources.php and look under
"Clinician Information" for more information.
