Slow virus infections.

Slow viruses produce diseases whose incubation periods range from several months to many years. Because of this long latency period, the lack of inflammation produced by these diseases and the lack of recoverable virus particles, it is only recently that the association has been made between the viruses and the diseases they cause. The detailed study of kuru, a neurologic affliction of a remote tribe of cannibals in New Guinea, was responsible for the synthesis of new and previously gathered information into a unified framework to explain not only kuru but other diseases as well. Since then, animal models, transmission experiments and histologic and biochemical studies have unveiled new links connecting viruses to previously obscure neurologic, neurophthalmic and ophthalmic entities.