Virological supervision of bluetongue disease in the south-east region of Romania

Abstract

Bluetongue is an infectious, non-contagious, vector-transmitted viral disease affecting domestic ruminants (sheep, goats, cattle) and wild (buffaloes, deer, several species of African antelopes and other species of the Artiodactyla order). The economic importance of the disease lies in the important economic losses following the decrease in the productive capacity of the animals, mortality and fetal malformations, immunization costs of the receptive animals, trade restrictions, reduction of the economic recovery price of the receptive animals and products thereof. Our study aimed at identifying by virological examinations the presence and circulation of BLA virus in the SE region of Romania. For viral isolation and identification were used blood samples collected from domestic ruminants in the counties: Galati, Braila, Tulcea and Vrancea. According to the working chart of the BT Diagnostic Manual (LNR Arboviroze Bucharest), the samples collected from suspect animals were processed and tested by RT-PCR. In the period 2015-2016, 517 blood samples with anticoagulant from 282 cattle and 235 sheep suspected of Bluetongue were tested for the identification of the viral genome by RT-PCR technique. There were no suspicions of Bluetongue disease in goats in the counties included in the study. In bovines in the SE of Romania, the viral genome was identified in 171 (60.64%) blood samples with anticoagulant. In sheep in the SE of Romania, the viral genome was identified in 209 (88.93%) blood samples with anticoagulant. Most positive samples confirmed by the detection of the BT viral genome came from Vrancea, both in cattle (161 positive samples) and in sheep (209 positive samples). Because of the pathogenicity, bluetongue virus infection can not be diagnosed for a certain period of time, the period in which the disease may exist and evolve, the infected animals being sources of infection for vectoric culicoid insects.