Virologic and serologic investigations of West Nile virus circulation in Belarus.

In 1985-1994 virologic and serologic investigations were performed for the purposes of West Nile (WN) virus circulation establishment on the territory of Belarus. Blood-sucking mosquitoes, midges, wild small mammals, birds as well as blood and cerebrospinal samples from patients with nondifferentiated fevers and from healthy individuals were under studies. Four virus strains were isolated in Belarus for the first time, namely: 1--from birds (48-WN Tremlya); 2--from Aedes mosquitoes (319 and 2438); 1--from a febrile patient (Win). Their antigenic and biological properties were examined in cell cultures and laboratory animals. The isolates turned to be identical with each other and closely related to reference Egypt strain Eg 101, that is a topotype for the African virus group. One more WN virus strain (8891) was isolated from Anopheles mosquitoes in 1999. Specific antibodies to the virus in human blood sera were identified by immunological and serologic assays in 1.7% of Belarusian population. In Gomel and Brest Regions the percentage of seropositive individuals reached 5.8 and 15.4, respectively. WN virus antibodies prevailed in 0.6-5.8% of cattle, in 2.9-6.8% of wild small mammals and in 6.5-16.7% of birds. Thus, the conclusion was made on the existence of favourable conditions for the virus spread throughout the whole country and in the south in particular. Blood-sucking mosquitoes and birds are principle vectors in WN virus circulation in Belarus. 16 serologically confirmed cases of WN encephalitis were revealed in patients with fever of obscure etiology. In the view of the given data, reports on the reemergence of the pathogen in different countries and the tendency in global warming WN virus monitoring should become a subject of concern for Belarusian public medical care services.

[The efficacy of lincomycin in tick-borne encephalitis]. / Ob éffektivnosti linkomitsina pri kleshevom éntsefalite.

Lincomycin was found to inhibit tick-borne encephalitis (TBE) virus. To test antiviral potential of this drug, a clinical trial was initiated entering TBE patients from known focuses of the disease (Novosibirsk, Kemerovo, Perm and Irkutsk Provinces). The drug was given to 23 patients with meningeal and meningoencephalitic TBE. A control group of 22 matched subjects received specific immunoglobulin. Resultant efficacy of lincomycin appeared not inferior to that of anti-TBE immunoglobulin. Lincomycin can be successfully introduced in the treatment of meningeal and meningoencephalitic TBE.

[Kindia virus--a new arbovirus isolated in the territory of the Republic of Guinea]. / Virus Kindia--novyi arbovirus, vydelennyi na territorii Gvineiskoi respubliki.

Circulation of a new arbovirus named Kindia has been detected in Guinea Republic. The virus was isolated from ixodid ticks and blood-sucking mosquitoes and, on the basis of the studies done, has been classified into the antigenic group Paliam, genus Orbivirus, family Reoviridae.

[Effect of gamma irradiation on immobilized trypsin]. / Vliianie gamma-oblucheniia na immobilizovannyi tripsin.

The effect of ionizing radiation of 0.05-10 Mrad on trypsin immobilized on dialdehyde cellulose was being studied. After irradiation the activity of native trypsin decreases by 25%, as compared with the initial, while the activity of immobilized trypsin remains constant. Before immobilization cellulose undergoes special pretreatment that leads to a decrease in the initial contamination. Some samples of modified cellulose were contaminated by staphylococcus culture (200,000 microbes per 0.2 g) and then exposed to irradiation of 0.05-0.4 Mrad. A distinct correlation between the irradiation dose (0.05-0.4 Mrad) and contamination of the object was registered.