Saint Louis Encephalitis is a virus, related to West Nile virus, transmitted by the bite of an infected mosquito. Culex tarsalis and to a lesser extent Culex pipiens are the mosquito species responsible for transmitting St. Louis Encephalitis.
St. Louis Encephalitis is similar to West Nile virus in that it is primarily a bird-mosquito disease. A mosquito will bite a bird infected with St. Louis Encephalitis and become infected. While looking for another blood meal, an infected mosquito can infect an uninfected bird or human.
What are the signs and symptoms of St. Louis Encephalitis?
No Symptoms: Most of those infected with St. Louis Encephalitis will have no symptoms or signs and never feel sick
Mild Symptoms: Most of those who do have symptoms or signs will have a fever and headaches
Severe Symptoms: Few of those infected have the severe symptoms such as high fever, severe headaches, coma, tremors, convulsions, paralysis, and possible death
Is St. Louis Encephalitis seasonal?
Yes, it is most likely to occur in late summer to early fall.
Is St. Louis Encephalitis in San Mateo County?
St. Louis Encephalitis is sometimes detected in Southern California but has not been found in San Mateo County recently.
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Website Accesibilty Policy San Mateo County Mosquito and Vector Control District
San Mateo County Mosquito and Vector Control District is fully committed to providing accessible facilities, elements and
channels of communication to all members of the public. As part of this commitment, San Mateo County Mosquito and Vector Control District
has a policy of providing an accessible website compatible with the Web Content Accessibility Guidelines (WCAG 2.1) and
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other impairments to understand and use the website to the same degree as someone without disabilities. We welcome
feedback and can often resolve issues in a timely manner if they arise.
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San Mateo County Mosquito and Vector Control District has designated a compliance officer for website disability-related accommodations.
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In addition to testing with users with a wide range of disabilities and coding our website to WCAG standards,
San Mateo County Mosquito and Vector Control District regularly scans its website to ensure ongoing compliance, and makes timely
changes to any inaccessible changes, if any are found. In our ongoing commitment to transparency, we make the
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August 2021 Website Accessibility Compliance Report
July 2021 Website Accessibility Compliance Report
June 2021 Website Accessibility Compliance Report
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