Rabies & Mosquito-Borne Diseases


Animal Services works with the Health Officer, veterinarians, and the entire community to help prevent the spread of rabies in Lake County. Rabies is a viral infection transmitted in the saliva of infected mammals. The virus enters the central nervous system of the host, causing an encephalomyelitis that is almost always fatal if not treated before symptoms appear.

  • Cats are not required by law to be vaccinated annually against rabies in Lake County.
  • State and local laws require dogs over four months of age to be vaccinated against rabies. The initial vaccination is good for one year. After that, rabies vaccinations are needed every three years.

What You Can Do

It's up to all of us to prevent rabies. Here's what you can do:

  • Vaccinate all domestic cats and dogs. It's the single most important step you can take to prevent rabies, and it's required by law for all dogs age four months and older. Learn more by visiting the Centers for Disease Control and Prevention's (CDC) Rabies Vaccination webpage.
  • Never handle wildlife and teach your children to admire wild animals from a distance.
  • Get vaccinated against rabies. If you work with domestic or wild animals or in situations in which you might be exposed to wildlife (especially bats), consider getting vaccinated.
  • Report exposure or potential exposure to rabies:
    • If you have been bitten by an animal or think you have been exposed to rabies, call the County of Lake Communicable Disease staff at 707-263-1090.
    • If your pet has been bitten by an animal or think they have been exposed to rabies, call Lake County Animal Control at 707-263-0278.
    • If you suspect a wild animal has rabies, call Lake County Animal Control at 707-565-7100.


  • Do not handle or feed wild animals.
  • If you think you may have been exposed to rabies, contact your doctor.
  • Any bite from a wild or unknown animal should be considered as a possible source of rabies.

The Lake County Health Officer will be notified of all bites at risk for possible rabies exposure that cannot be handled by standard quarantine of domestic animals under the supervision of Animal Care and Control. County of Lake Health Services' experienced nursing staff follows up on each bite report by conducting a case investigation. They provide rabies education, guidance for access to post-exposure prophylaxis/vaccination (PEP), and contact information for future questions.

California Rabies Surveillance Annual Report

To see where rabies has been detected in both domestic and wild animals in California view the Rabies Surveillance in California Annual Report.

Mosquito-Borne Diseases

Throughout the summer and fall mosquitos thrive in Lake County, it is important to take precautionary steps to avoid mosquito bites that can transmit disease-causing viruses.

Learn more by visiting the CDC Mosquitos webpage.

What is West Nile Virus?

West Nile Virus (WNV) is a disease carried by mosquitoes that is common in Africa, west Asia, the Middle East and more recently North America. Human infection with WNV may result in serious illness. Experts believe WNV is established as a seasonal epidemic in North America that flares up in the summer and continues in the fall.

How is West Nile Virus Transmitted?

Infected Mosquitos. Most often, WNV is spread by the bite of an infected mosquito. Mosquitoes are carriers that become infect when they feed on infected birds. Infected mosquitoes can then spread WNV to humans and other animals 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 the virus.

West Nile Virus Resources

For additional information visit Centers for Disease Control and Prevention (CDC) West Nile Virus or California West Nile Virus Website.

Is Zika Virus Still a Concern?

Dengue, chikungunya, and Zika virus outbreaks have occurred in U.S. states and territories, including Florida, Hawaii, Texas, Puerto Rico, the U.S. Virgin Islands, and American Samoa.

What We Know

  • Zika is spread mostly by the bite of an infected Aedes species mosquito (Ae. aegypti and Ae. albopictus). These mosquitoes bite during the day and night.
  • Zika can be passed from a pregnant woman to her fetus. Infection during pregnancy can cause certain birth defects.
  • There is no vaccine or medicine for Zika.

Risk of Zika

  • There is no current local transmission of Zika virus in the continental United States.
  • The last cases of local Zika transmission by mosquitoes in the continental United States were in Florida and Texas in 2016-17.
  • Since 2019, there have been no confirmed Zika virus disease cases reported from United States territories.

For more information, visit the CDC Zika Virus webpage.