This parasitic protozoan is resistant to metronidazole and can be used in antimicrobial resistance research, drug development, infectious disease research, and sexually transmitted disease research.

Pneumocystis carinii strain M167-6 was isolated in October 2003 from the lungs of an immunosuppressed Lewis male rat in Cincinnati, Ohio.

Human herpesvirus 1 strain F is propagated in HEp-2 cells (ATCC CCL-23).

Denitromonas iodocrescerans TSD-242

Nuclear polyhedrosis virus, Autographa californica VR-992

Enterovirus D68 strain Fermon is propagated in MRC-5 cells (ATCC CCL-171). This strain was isolated from a nasopharyngeal swab from of a 10-month-old female hospitalized in California in 1962.