This mostly threatens the parasite and pathogen species that are highly host-specific to critically endangered hosts.
When the last individuals of a host species are captured for the purpose of captive breeding and reintroduction programs, they typically undergo anti-parasitic treatments to increase survival and reproductive success.
A few cases of conservation-induced extinction have occurred in parasitic lice.
[1] The trichodectid louse of the black-footed ferret has been mentioned in the literature several times[7] as a parasite that became extinct during the captive breeding program of the host.
However, this parasite most probably never existed as a separate species from Neotrichodectes minutus.