Geographical distribution of arboviruses in Yugoslavia.

Studies of arboviruses started in Yugoslavia in 1953 following the isolation of TBE virus which caused a severe epidemic that year. Until now the following viruses have been proven to circulate in the country: tick-borne encephalitis (TBE), Crimean-Congo hemorrhagic fever (CCHF), Bhanja (BHA), sandfly fever (SF), Tahyna (TAH), Calovo (CVO), West Nile (WN), dengue (DEN), Jug Bogdanovac (JB), and Hantaviruses. TBE virus is endemic in the north-west part of the country, causing also epidemics in cyclical intervals.

Neutralizing antibodies for sandfly fever Naples virus in human sera on the island of Mljet.

Sera from apparently healthy residents of various age from different localities of the Adriatic island of Mljet were tested by the plaque reduction neutralization test (PRNT) for antibodies to sandfly fever Naples virus (SFN). An average of 51.4% of the sera examined was found to have neutralizing antibodies.

Incidence of hemagglutination-inhibiting antibodies for Bhanja virus in humans along the north-west border of Yugoslavia.

By the hemagglutination-inhibition test with the Yugoslav strain of Bhanja virus, the sera of 380 youngsters residing in the region along the Yugoslav-Hungarian border (North Croatia) and 367 sera from newcomers to the area from various parts of Yugoslavia were examined. The testing included 154 sera of the youngsters who had came to the region along the Yugoslav-Italian border (Slovenia) without antibodies for Bhanja virus and were staying there for a year. Hemagglutination-inhibiting antibodies for BHA virus were found in the sera of 5.

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.

Serological studies on the epidemiology of sandfly fever in the Old World.

Selected human sera from 59 different localities in Africa, the Mediterranean littoral, eastern Europe and Asia were examined by plaque reduction neutralization test against eight sandfly (Phlebotomus) fever virus serotypes (Sicilian, Naples, Arumowot, SudAn 754-61, Karimabad, Salehabad, Gordil and Saint Floris) known to occur in the Old World. Results of these studies provide new information on the geographic distribution and prevalence of human infection with each of the viruses. Specific neutralizing antibodies were detected against all of the agents except Salehabad.

Arbovirus infections in Ceylon.

The haemagglutination-inhibition test has been used to assess the frequency of arbovirus infections in the population of Ceylon, by age-group, and also in some animals. The antigens used were: chikungunya, JE, dengue 1, 2, 3, 4, and Tahyna.The percentage of positive reactors to the group-B viruses ranged from 16.