Serological Detection of Peste des Petits Ruminants Virus (PPRV) Antibodies among Sheep and Goats in River Nile State, Sudan

Abstract

Between January 2018 to December 2019, many suspected outbreaks of PPR were reported among flocks of sheep and goats in the seven localities of the River Nile State in the northern part of the Sudan. The present study was designed to investigate the presence of peste des petits ruminants virus (PPRV) antibodies among sheep and goats in the River Nile State, Northern Sudan. Serum samples were collected from 19 suspected PPR outbreaks occurred in seven localities of the River Nile State. A total of 483 serum samples were collected from sheep (337 sera) and goats (146 sera). Animals had no previous history of vaccination against PPR. Sheep and goats sera were screened using haemagglutination-inhibition (HI) test for detection of PPRV antibodies. Sera with HI titers less than 8 were considered as negative whereas sera with HI titers more than or equal to 8 were considered as positive and protective. Of the total 483 serum samples (337 sheep and 146 goats) tested, 470 sera were positive, with an overall antibodies sero-prevalence of 97.3%, while only 13 (2.7%) samples were negative. Results of the haemagglutination-inhibition test revealed titers ranged from 8 to 256 with an overall mean HI titer of 52.6. On the species basis, within sheep 324/337 (96.1%) sera were found positive whereas only 13/337 (3.9%) sera were negative. Within goat all tested sera (146/146, 100%) were found positive. As a conclusion goat sera yielded a higher overall sero-prevalence (100%) compared to sheep sera (96.1%). Results of the haemagglutination-inhibition test revealed titers ranged from 8 to 256 with mean titer of 48.9 among sheep and 61.3 among goats. Sero-prevalence of PPRV antibodies within localities of the River Nile State demonstrated the highest overall sero-prevalence of PPRV antibodies (100%) in Shendi and Berber localities with relatively lower sero-prevalence demonstrated in Ad-Damar (98.8%), Abu Hamad and Elbohira (97.4%) and Atbara (94.8%) and the least sero-prevalence was demonstrated in Elmatama (90.0%). The higher titers of PPRV antibodies detected in sheep and goats sera in all localities of the River Nile State, where outbreaks occurred, suggested the wide exposure of these animals to PPRV although it was, until recently, considered as a disease free zone.