What to know
- The CDC Rickettsial Isolate Reference Collection (CRIRC) is housed within the Rickettsial Zoonoses Branch at the Centers for Disease Control and Prevention in Atlanta, Georgia.
- The collection serves as a repository for reference strains.
- The CRIRC contains more than 300 isolates of species of Anaplasma, Ehrlichia, Neorickettsia, Orientia, and Rickettsia.
- DNA and viable culture samples can be requested.

Mission
The CDC Rickettsial Isolate Reference Collection (CRIRC) preserves the work of generations of rickettsiologists and public health scientists to support current public health science and research by providing quality bacterial cultures and DNA samples at no cost to other public health and research institutions in the United States.
Requesting samples from the CRIRC
If you are interested in requesting an isolate or DNA sample, download and submit a request form to CRIRC@cdc.gov.
Note: In general, the CRIRC does not support large-scale requests for isolates or DNA. Requests for more than five isolates or DNA samples will be reviewed on a case-by-case basis.
Questions?
For questions about the CRIRC, contact CRIRC@cdc.gov
For all other questions, Contact CDC-INFO
International requests
- International requesters are required to pay the cost of shipping.
- The requester is responsible for procuring the required paperwork and permits for the country of import.
- CDC is not responsible for delays in shipping or customs clearance due to missing or incorrect paperwork.
Commercial requests
All commercial requests will require review by CDC's Technology Transfer Office.
Contents and maintenance
Contents of the collection
The CRIRC consists of over 300 bacterial isolates from arthropod, animal, and human sources including contemporary and historical isolates dating back to 1935.
As of May 21, 2025, the CRIRC collection includes:
*Note: Laboratory work with Rickettsia spp. may be conducted in a BSL-2 facility with enhanced special practices including strict access control, competency, and adherence to BSL-3 practices. BSL-3 practices include, but are not limited to, appropriate personal protective equipment (e.g., rear-closing gowns, gloves, eye protection, and respiratory protection such as N95 respirators or PAPRs), use of biological safety cabinets when handling any open container with potentially infectious material, and primary containment, such as sealed centrifuge rotors and other means of containment outside the BSC. For more information, see Biosafety in Microbiological and Biomedical Laboratories (BMBL) 6th Edition | CDC Laboratories.

Quality control testing
- Species confirmation using polymerase chain reaction and sequencing
- Select-agent screening for Coxiella burnetii and Rickettsia prowazekii
- Inclusivity and exclusivity testing
- Mycoplasma contamination testing
- Mycoplasma clearance using antibiotics