Diseases and Surveillance - Vector Control District

Canine Heartworm

Canine Heartworm Disease impacts around 250,000 dogs out of 50,000,000 dogs every year. This disease is caused by a bite of the Western Treehole Mosquito (Aedes sierrensis).

West Nile Virus

West Nile Virus (WNV) is a mosquito-borne disease that was first detected in the West Nile District of Uganda. Transmitted by mosquito bites, WNV affects humans, horses, some birds, and squirrels.

A close-up image of a mosquito on a person's thumb

Lyme Disease

Lyme disease is caused by the bacterium Borrelia burgdorferi and is transmitted to humans through the bite of infected blacklegged ticks.

A close-up image of a tick on a green leaf

Western Equine Encephalitis

Western equine encephalitis is a disease that is spread to horses and humans by infected mosquitos. It is one of a group of mosquito-borne virus diseases that can affect the central nervous system and cause severe complications and even death. Other similar diseases are eastern equine encephalitis, St Louis encephalitis, and La Crosse encephalitis.

A close-up image of a mosquito on a rough surface

Arenavirus in California

Arenavirus infection linked to deaths California. SACRAMENTO

A close-up image of a black rat on a wood surface

Hantavirus Pulmonary Syndrome

Hantaviruses are a family of viruses named for the Hantaan River in Korea, where the first strain was discovered decades ago.

A close-up image of a brown rodent on a gravel surface

Leptospirosis

Leptospirosis is a bacterial disease that affects humans and animals. The incubation period is commonly about10 days (range, 2 days to 4 weeks). Symptoms can include flu-like illness (high fever, headache, chills, muscle aches), jaundice, conjunctivitis, abdominal pain, vomiting, diarrhea, and sometimes a rash.

Common Raccoon Roundworm

"Raccoons are peridomestic animals, which means they live in or around areas where people live. Roundworm eggs are passed in the feces of infected raccoons. Raccoons defecate in communal sites, called latrines. Raccoon latrines are often found at bases of trees, unsealed attics, or on flat surfaces such as logs, tree stumps, rocks, decks, and rooftops. As more raccoons move into populated areas, the number and density of their latrines will increase." -CDC