Serological Investigation and Molecular Detection of Newcastle Disease Virus From Apparently Healthy Village Chicken in East Gojjam Zone, Ethiopia

Newcastle disease (ND) is a notifiable and highly contagious disease causing a significant economic loss in village chicken production. So, a cross-sectional study was conducted in the East Gojjam zone of Ethiopia to determine the status of ND among unvaccinated village chickens. The study sites were selected randomly. However, the chicken owners included were households that had at least four chickens with no prior history of ND vaccination. A total of 314 serum and 76 pooled tracheal and cloacal swab samples were collected from apparently healthy birds. The hemagglutination inhibition (HI) test and reverse-transcription polymerase chain reaction (RT-PCR) were conducted for serological and virological tests, respectively. The data were analyzed using the SPSS version 20 software package. Descriptive statistics and generalized linear mixed models were used for data analysis. The overall seroprevalence rate at the individual chicken level was found to be 93% (292/314 chickens). At the household level, ND was identified in all sampled households, with a minimum of two seropositive chickens found in each household. However, these chickens tested negative for the ND virus by RT-PCR. The seroprevalence rates of the NDV at each study site were 95.0%, 96.0%, and 86.9% for Gozamin, Enemay, and Debre Elias woredas, respectively, with a statistically significant difference (p