Alameda County: Tularemia Surveillance 2006-2007

Annual Report 2006-2007, Alameda County Vector Control Services

Tularemia is caused by the bacterium Francisella tularensis that infects a variety of arthropods and vertebrates. Symptoms of human tularemia may include fever, chills, malaise, and fatigue. The disease is commonly transmitted by contacts with rabbits, insects, or tick bites. In Alameda County, a confirmed human case, transmitted by an American dog tick, Dermacentor variabilis was reported by CDHS in 2004. Since tularemia is classified as a bio-terrorism agent, the CDHS requested blood samples from various animals for testing. In 2006, 12 rodent samples were submitted; results are still pending.

Alameda County: Lyme Disease Surveillance 2006-2007

Annual Report 2006-2007, Alameda County Vector Control Services

As part of the Lyme disease surveillance program, our staff collects and identifies ticks, and recommends testing for tick borne disease when deemed appropriate. Our District provides consultations, educational resources, tick identification, and testing facilities for Lyme disease. Fifteen Ixodes pacificus ticks were submitted to the Sonoma County Public Health Laboratory for Lyme disease testing; all tested negative. The District now has the capability to perform Lyme disease indirect fluorescent antibody (IFA) tests. We hope to expand this capability when new staff is hired.

San Mateo County: Population Dynamics of the American Dog Tick and Pacific Coast Tick

Entomology Report June 2007, San Mateo County Mosquito Abatement District

District staff have been monitoring the seasonal population dynamics of the American Dog tick (Dermacentor variabilis) and the Pacific Coast tick (Dermacentor occidentalis) along the coast this year. These ticks are potential vectors of tularemia and Rocky Mountain Spotted Fever in California. Human cases of these diseases appear to have been acquired in San Mateo County during the past 3 years. Cases of tularemia have occurred in children camping south of Pescadero in 2004 and 2006. In 2004, a tick removed from a patient tested positive and in 2006, infection was detected in local ticks collected in the same area.

Adults of these ticks appear during spring and summer months. Because they are not vectors of Lyme disease, they have not been surveyed by District staff as extensively as the Western black-legged tick. The District is now sampling for these ticks on a weekly basis to further characterize their seasonal population trends. This information will be incorporated into public education campaigns that teach people to avoid tick-borne diseases.

Previous related entries:

San Mateo County: Tularemia Detected in Coastal Ticks, September 2006

San Mateo County: Physician Survey on Lyme Disease

Entomology Report June 2007, San Mateo County Mosquito Abatement District

In conjunction with the San Mateo County Public Health Department, laboratory staff have surveyed over 100 physicians throughout the county to assess physician beliefs and awareness about Lyme Disease. So far, 9% of the surveys have been completed and returned. This survey will be used to develop educational materials, geared towards physicians, informing them of the risk of acquiring Lyme Disease in the county.

Previous related entries:

Survey of San Mateo County Physicians on Lyme Disease, March 2007
San Mateo County Physician Survey on Lyme Disease, November/December 2006