County of Marin Health and Human Services

Public Health Laboratory Services

Effective immediately

The Public Health Laboratory will no longer test the Dermacentor species ticks for the presence of Borrelia burgdorferi. Dermacentor variabilis, also known as the American dog tick, is the most common species found in California.

Studies show that only the Ixodes species ticks can infect a host with B. burgdorferi upon blood-feeding. Ixodes pacificus, also known as the western blacklegged tick, is the most common species found in California. The Public Health Laboratory will continue testing the Ixodes species ticks for B. burgdorferi.  

The laboratory will still accept and identify the Dermacentor species ticks. The fee for identification and/or testing will remain the same ($35), regardless of the type of the tick submitted. No refunds will be issued.

The Public Health Laboratory offers bacterial testing for well-water safety and tick identification for Lyme disease upon request.

Note – Ticks are only accepted by mail to:

Napa/Solano/Yolo/Marin Public Health Laboratory
2201 Courage Drive MS 9-200
Fairfield, CA 94533

FeesPlease make checks out to: Public Health Laboratory.

Effective May 8, 2019, the Public Health Lab began accepting online payments. You will still need to complete a laboratory requisition with your submission.  The receipt number generated by the online portal must be included on the requisition. Links to the online payment portals appear below:

Tick Payment Portal
Well Water Testing Payment Portal 

Tick Identification is $35.00*

See portal for well water testing prices.  There is a fee schedule with a list of options available via the well water testing payment portal link above. 

*Fees are subject to change without prior notice.

Tick Removal Procedure:

  • If possible, have someone else remove the tick from you.
  • Use tweezers or forceps rather than your fingers.
  • If you must touch tick use a tissue or gloves to protect your hand.
  • Grasp the tick's mouthparts as close to the skin as possible.
  • Gently pull the tick straight out, steadily and firmly. Do not twist or jerk the tick.
  • If mouthparts of the tick break off and remain in your skin, consult your physician.

Tick Collection Procedure:

  • Place tick into clean capped container or a zip-lock plastic bag. Place a piece of cotton or tissue moistened with tap water into the container with the tick. (Note: do not use alcohol, formalin or other liquids. Do not stick tick to scotch tape. These materials make testing for the Lyme organism unsatisfactory.)
  • Mail tick to Napa/Solano/Yolo/Marin Public Health Laboatory at 2201 Courage Drive MS 9-200, Fairfield, CA 94533. 
  • Complete a laboratory form and supply the following information:
    • Name, address and birth date of person bitten.
    • Location of the bite (arm, neck, etc.)
    • Date tick removed.
    • Estimated duration of time tick was attached (i.e. 4hrs, 24hrs, etc.)
    • Geographical location (what city, park, etc.) tick was obtained.
    • Phone number, name and address of person to receive report.
    • Any obvious symptoms.

Well Water Testing Information:

Due to the continued limitations resulting from COVID-19, the Marin County Public Health is changing the procedure for dropping off water samples. 

  • Effective Wednesday, March 17, 2021 water sample drop off hours will be 9:00am- 12:00pm and 1-1:30pm, Monday through Friday. The drop off location is closed from 12-1:00pm for lunch.
  • The drop off site remains at 3240 Kerner Blvd., San Rafael. Upon arrival at 3240 Kerner Blvd, please call 415-473-6868 for immediate assistance.

Please drop off your water samples the same day they are collected as they are time sensitive. For recreational beach water testing please perform sampling after 8:30am to ensure there is enough time to get the samples back to the lab and on test prior to the 8-hour sample expiration.

Please ensure the samples remain in a cooler with ice packs during delivery.

If you have any questions, feel free to call the NSYM Public Health Lab at 707-784-4410 or Marin County Public Health, Communicable Disease Control and Prevention at 415-473-4163.

Thank you for your understanding.