It can also be spread unwittingly by humans.

Health officials feared that the healers themselves were unwittingly spreading the fatal disease.

Omnius himself suffers badly from a computer virus created by Vorian and spread unwittingly by his old companion Seurat.

Dr. Ho speculated that H.I.V.-1 might have been unwittingly spread through things like shared needles in large-scale immunization programs for diseases like polio and smallpox.

Some are unwittingly spreading the human immunodeficiency virus to new victims.

Mr. Clark emphasized that the virus's long incubation period means many people unwittingly spread the virus.

But despite the warning's authentic appearance, city and union officials say it is a hoax, which seems to have first appeared in 1992 and that was unwittingly spread by Mr. Mannion.

Celia unwittingly spreads the news Carly Morris (Sharyn Hodgson) has been raped.

These plane-hopping leaders may be unwittingly spreading infectious diseases like the hot new worry, SARS, without anyone questioning whether they come here with clean hands.

Many people are unaware of their HIV status and could unwittingly spread the disease.