Seroprevalência da febre do Vale do Rift em bovinos no distrito de Matutuíne

Abstract

Rift Valley Fever (RVF) is a zoonosis caused by a virus belonging to the Phenuiviridae family and transmitted by biological vectors (mosquitoes of the Aedes and Culex genera). The disease mainly affects ruminants (sheep, goats and cattle), causing large epidemics with high mortality rates in young animals and abortions. The virus that causes RVF is found in regions of East Africa, Southern Africa, most of Sub-Saharan Africa, including West Africa, Madagascar and outside the African continent in Saudi Arabia and Yemen. In Mozambique, studies have shown evidence of the virus circulating in some provinces of the country, in both domestic and wild ruminants. there are few studies on the occurrence of RVF in the Matutuíne district. The aim of this study was to determine the seroprevalence of the virus in cattle in the district of Matutuíne, in the localities of Gala, Salamanga, Tinonganine, Macassane, Zitundo, Futi, Guengo and Matchia. A total of 491 blood samples were taken from cattle. The animals were categorised by age (calves, steers and adults) and sex (females and males). The blood samples were centrifuged to separate the serum and tested for RVF virus antibodies using an enzyme-linked immunosorbent assay (ELISA). The results revealed evidence of RVF virus circulation in cattle in the Matutuíne district. The overall seroprevalence was 31.9% (95% CI: 27.9 - 36.3), the highest prevalence was found in the locality of Guengo with 47.4% (95% CI: 30.9 - 64.2), followed by the localities of Futi and Tinonganine with 43.3% (95% CI: 30.6 - 56.8) and 41.2% (95% CI: 18.4 - 67.1) respectively. The lowest prevalence was found in Matchia with 20.7 per cent (95% CI: 7.9 - 39.7). The results showed that the geographical location and age of the animals were the risk factors for the occurrence of RVF. The high seroprevalence observed demonstrates the need to improve surveillance and control systems to prevent future outbreaks and the consequent economic impact of the disease in the Matutuíne district and other localities. (TRADUÇÃO NOSSA)