But separate strains at the two locations would suggest no such spread, only different infections limited to their respective prisons.

Several separate strains of the "bulldog" type dogs were kept by ranchers as utilitarian working dogs.

For example, an individual superinfected with two separate strains of HIV may contract a strain that is resistant to antiretroviral treatment.

The penultimate strain, R4b, can mutate into two separate strains, R4b1 and R4b2.

Why not two separate strains of humanity?

However, after 1980's selection for two separate strains (meat and milk or dual-purpose) were created by the breeders of this breed.

It occurs occasionally in flocks of other colours, but is now often maintained as a separate strain.

The prized Australian fish, the barramundi, breeds in the river along with sooty grunter and a separate genetic strain of golden perch.

By the beginning of the 20th century the Aylesbury duck had diverged into two separate strains, one bred for appearance and one for meat.

Growing international interest tended to bring the separate strains of regional New Orleans music together.