Skip to main content

Tick Surveillance

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

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 and B. miyamotoi  DNA using Real-Time PCR technology.  The District also collaborates with other agencies and educational institutions on various research projects related to ticks and tick-borne disease.

 

Minimum infection prevalence (MIP)
CountyStageBorrelia burgdorferiBorrelia miyamotoi
Marin CountyAdults2.06%1.24%
Nymphs 4.30%1.44%
Sonoma CountyAdults1.69%.61%
 Nymphs4.41%.97%
Marin & SonomaAdults1.86%.88%
 Nymphs4.35%1.20%

Additional resources

California Department of Public Health Tick-Borne Diseases

CDC “Surveillance for Ixodes pacificus and pathogesn found in this tick species in the United States”