Abstract:
Brucellosis is a worldwide zoonosis that is endemic in Namibia. This study estimated seroprevalence
of brucellosis, and determined the presence of Brucella infection in slaughtered cattle using the
genus-specific 16-23S rRNA interspacer PCR (ITS-PCR), and the species-specific AMOS-PCR. Between
December 2018 and May 2019, sera (n = 304), pooled lymph nodes (n = 304), and individual spleen
(n = 304) were collected from slaughtered cattle from 52 farms. Sera were tested for anti-Brucella
antibodies using the Rose Bengal test (RBT), and the complement fixation test (CFT). Seroprevalence
was 2.3% (7/304) (RBT) and 1.6% (5/304) (CFT). Prevalence of positive herds was 9.6% (5/52). Lymph
node (n = 200) and spleen (n = 200) samples from seronegative cattle tested negative for Brucella
spp. DNA on ITS-PCR, but Brucella spp. DNA was detected in lymph nodes (85.7%, 6/7) and spleen
(85.7%, 6/7) from RBT positive cattle. ITS-PCR confirmed isolates from lymph node (51.4%, 4/7) and
spleen (85.7%, 6/7) as Brucella spp.; while AMOS-PCR and Brucella abortus species specific (BaSS) PCR
confirmed the isolates as Brucella abortus, and field strains, respectively. Provision of adequate
protective gear, and the promotion of brucellosis awareness among abattoir workers is recommended
to prevent zoonotic infection.
