[The variola virus as a biological weapon].

In view of the threat of use of the variola virus as a biological weapon, the interest of medical and other public in this causative agent that was eradicated in the wild at the end of the 1970s has increased. The paper gives an outline of the current knowledge on biological properties of the variola virus, and on the epidemiology, pathogenesis, clinical picture and prophylaxis of the disease caused by this virus. Descriptions of two sudden smallpox epidemics (Germany in 1970 and former Yugoslavia in 1972) could illustrate the potential of the smallpox virus as a biological weapon in bioterrorism and biological warfare.

Natural foci of some viral zoonoses in Croatia.

Results of several-year investigations into the epidemiology and virology of viral zoonoses with natural foci occurring in Croatia, with special reference to tick-borne encephalitis (TBE) and hemorrhagic fever with renal syndrome (HFRS), are presented. The etiologic diagnosis of these diseases was made on the basis of virus isolation from patient blood and/or findings of specific antibodies in the serum. Several TBE and Bhanja virus strains were isolated from different species of ticks, and Calovo virus from mosquitoes, while the presence of Hantaan virus antigen was determined in the lungs of certain micromammalian species, the virus natural reservoirs, by direct immunofluorescence.

Arboviruses in Croatia.

This paper lists the arboviral infections which occur in Croatia. Individual diseases are described chronologically, with the evidence of their etiologic diagnosis based on the isolation of the causative virus and/or finding specific antibodies in clinical material. Virus circulation in the natural foci of arboviral infections was determined by virus isolation from the collected vectors and by finding specific antibodies in animal sera.

Prions and prion diseases.

Currently known transmissive spongiform encephalopathies in humans and animals are presented. Caused by prions, they are known as "prion disease". The results of extensive investigations of prions are described, as well as the theories about their nature.

Isolation of Bhanja virus from ticks in Yugoslavia.

Two strains of Bhanja (BHA) virus, an ungrouped arbovirus, were isolated from Haemaphysalis punctata ticks collected from sheep on the island of Brac in the Yugoslavian Adriatic. Serologic testing gave evidence of the endemicity of BHA virus on the island, and antibody prevalence rates were high for both man (35.8%--ranging locally to 61.