Arbovirus-related encephalitis.

Arthropod-borne virus encephalitis in the U.S.A. includes LaCrosse, St Louis, western equine, eastern equine, Venezuelan equine, and Powassan in that order of frequency. Diagnosis can be aided by the history of seasonal occurrence, climate, geographic location, exposure to vectors, and age of the patient. The definitive diagnosis is usually made by serological tests such as neutralization, complement-fixation, hemagglutination-inhibition, and immunofluorescence, the radioimmune assay and the enzyme-linked immunosorbent assay show promise of future utility. These diseases are prevented by vector control. It is unlikely that vaccines or anti-viral agents will have application in the near future.     

Prognosis in tick-borne encephalitis

The paper presents a review of suggested and used methods of predicting the number of the main vector and its infection with the tick-borne encephalitis virus. It has been suggested that most practically important are long-term prognoses of tendencies in the changes of the parasitic system on the basis of retrospective estimation of the recurrence of its changes, that is, the definition of probability of recurrence of most important characters (states) of a parasitic system in the presence of appropriate external conditions.