Tick Surveillance

Overview:

• The District collects western black-legged ticks (Ixodes pacificus) to test for the presence of Borrelia burgdorferi, the bacterium that causes Lyme disease, and Dermacentor spp. for collaborative research efforts.

Collecting ticks:

• District staff collect ticks at various parks and other publicly owned lands in Marin and Sonoma counties by a method called flagging. Ticks are sorted by species, gender and collection location, and are frozen until they are tested. 

 Testing ticks:

• Western black-legged ticks (I. pacificus) are tested for the presence of B. burgdorferi DNA using Real-Time PCR technology.  
• In 2009, District lab staff conducted research on using Real-Time PCR for testing ticks for B. burgdorferi. The research resulted in a poster that was presented at two professional conferences and a paper that was published in the 2010 Mosquito & Vector Control Association of California Proceedings and Papers.  
• In 2012, the overall minimum infection rate (MIR) in I. pacificus adults for Marin and Sonoma counties was 2.3% and 3.0% respectively. The overoverall minimum infection rate (MIR) in I. pacificus nymphs for Marin and Sonoma countieswas 3.9% and 4.7% respectively. Click here for a summary of results for 2012.
• The District collaborates with other agencies and educational institutions on various research projects related to ticks and tick-borne disease. In 2010 the District collaborated on a poster with Humboldt State University on the prevalence, density, and geographic distribution of two novel Rickettsia species in I. pacificus.

Useful links: