Exposure to Brucella spp. in Goats and Sheep in Karenga District, Uganda Diagnosed by Modified Rose Bengal Method

Abstract

A retrospective study was conducted in 2022 to determine the seroprevalence of brucellosis and its risk factors among goat and sheep herds in the Karenga district, Karamoja region, Uganda. Sera from 332 goats and 81 sheep from 20 kraals in all seven administrative units of the district were tested using the modified Rose Bengal test (mRBT). It was determined that brucellosis was present in 20% of the small ruminant herds in the Karenga district, with an overall animal level seropositivity of 3.39% (CI: 1.87–5.62%; n = 14/413). Higher seropositivity was recorded in goats (3.92%, CI: 2.1–6.6%) than sheep (1.23%, CI: 0.03–6.69%). Similarly, seropositivity was higher in females (3.95%, CI: 2.12–6.66%) than males (1.19%, CI: 0.03–6.456), and also higher in goats and sheep more than two years old (4.15%, CI: 2.09–7.31%) than those one to two years old (1.98%, CI: 0.24–6.97%) or those less than one year old (2.13%, CI: 0.05–11.29%). Only herd size was statistically significant (p < 0.05) as a risk factor for exposure to brucellosis in the Karenga district. Although the prevalence of brucellosis among goats and sheep in the Karenga district is low, there still exists a risk to the pastoralists who closely interact with the animals and also practice risky behaviours such as consumption of uncooked or unpasteurised goat milk. There is need to expand herd health messaging in Karenga to include risk communication on brucellosis and other zoonotic diseases.

Seroprevalence and risk factors of brucellosis in pastoralists and their livestock in South Sudan

“…Additionally,[10] reported a higher seroprevalence of 3.92% (13/332) in goats compared to 1.23% (1/81) in sheep in Karega District, Uganda.…”

“…loss of work days, lost leisure time, loss of productive years due to premature death [8]. Studies have shown that brucellosis is high in pastoral and mixed farming system where humans have been embedded with livestock, so it constitutes a high risk of infection [9][10][11][12][13].…”

“…Furthermore, several studies within the African region have identified several risk factors and reported varying prevalence levels of brucellosis based on spatial and temporal features, diagnostic methods, and species. [9,10,[13][14][15]. However, few studies have been conducted in South Sudan to assess the prevalence of brucellosis in 6 humans and cattle [16][17][18][19].These studies have reported seroprevalence of 23.2% (48/250) [17]and 23.3% (97/416) [16]in cattle and humans, respectively.…”

“…Furthermore, several studies within the African region have identified several risk factors and reported varying prevalence levels of brucellosis based on spatial and temporal features, diagnostic methods, and species. [9,10,13–15].…”

Sero-prevalence and risk factors associated with occurrence of anti-Brucella antibodies among slaughterhouse workers in Uganda

“…Brucellosis is endemic in Uganda and is a priority zoonosis for control [ 35 ]. Although important in major food animals in Uganda, particularly cattle and goats [ 20 , 36 ], information about human brucellosis is scanty. According to a widely cited review, the incidence in Uganda is 0.9 cases per million but this estimate is based on incomplete WHO records of the year 2004 [ 37 ].…”