Update on rabies diagnosis and treatment.

The diagnosis of rabies depends on recognizing the clinical picture, because a history of an animal bite may be present or absent. Laboratory tests, particularly when based on detection of rabies virus antigen or RNA in tissues or fluids, often confirm the diagnosis. Negative laboratory tests do not exclude the diagnosis unless they are performed on brain tissues. Preventive therapy, including wound cleansing and active and passive immunization after a recognized exposure, is well established and highly efficacious. No established therapy exists that is effective for patients with rabies encephalomyelitis. The Milwaukee protocol involves induction of therapeutic coma; however, there is no clear rationale for a neuroprotective role of this therapy, many reports exist of its failures, and its use should be abandoned. Basic research is needed on the mechanisms of rabies pathogenesis. This may allow the development of new therapeutic approaches for this ancient disease.