Prevalence of bovine tuberculosis in cattle, goats, and camels of traditional livestock raising communities in Eritrea

Abstract

BackgroundThe aim of the current study was to assess the prevalence of bovine tuberculosis (BTB) in cattle, goats, and camels, and its zoonotic potential within the traditional livestock raising communities in four regions of Eritrea. The Single Intradermal Comparative Tuberculin Test (SICTT) as indicator of M. bovis infection was conducted on 1077 cattle, 876 goats, and 195 camels. To elucidate possible risk factors for BTB transmission between animals and its potential zoonotic implication, questionnaire based face-to-face interviews were conducted in households of which 232 raised cattle, 128 goats, and 29 camels.ResultsThe results of the SCITT were interpreted using the OIE standard (> 4 mm cut-off) for positive responses. In cattle, individual animal (n = 1077) and herd (n = 413) prevalences were 1.2% (n = 13) [Confidence Interval (CI) 95% CI, 1.0–1.3%] and 3.2% (n = 13) (95% CI, 3.0–3.4%), respectively. In goats (n = 876), none of the animals was positive. In camels, individual animal (n = 195) and herd (n = 70), BTB prevalences were 1.5% (n = 3) (95% CI,1.4–1.6%) and 2.9(n = 2) (95% CI, 0.9–4.6%), respectively. Overall, male animals were more at risk (OR = 2.6; 95% CI:1.0–8.7) when compared to females. Sharing of water points, introduction of new animals into herds and migration of animals over large distances were common events that may contribute to intra and inter-species transmission of BTB. Consumption of raw milk, lack of BTB transmission awareness, and low levels of education were common in the farming communities.ConclusionThe current study highlighted a low prevalence of M. bovis in cattle, goats and camels in extensive traditional livestock in Eritrea. Despite this, the spatial distribution of affected animals across most of the sampled regions and consumption of unpasteurized milk warrants surveillance, cautious and timely control measures for the disease.Electronic supplementary materialThe online version of this article (10.1186/s12917-018-1397-0) contains supplementary material, which is available to authorized users.

Isolation, identification and associated risk factors of non‐tuberculous mycobacteria infection in humans and dromedary camels in Samburu County, Kenya

“…Screening using the SICTT, the proportions of positive reactors were much higher than the findings from similar studies in Eritrea, 1.5%, M. bovis PPDreactors (Ghebremariam, Michel, Vernooij, Nielen, & Rutten, 2018) and in Kenya, 3.57% and 18.18% (Lamuka, Njeruh, Gitao, & Abey, 2018) and Ethiopia, 0.4% and 10% (Gumi, Schelling, Berg, et al, 2012; Gumi, Schelling, Firdessa, et al, 2012), bovine and avian PPDreactors, respectively. The difference in induration from the two studies could be due to several host, environmental and procedural factors (Chambers, 2013; Tschopp & Aseffa, 2016).…”

“…(2018) in Eritrea, consumption of raw milk, lack of zoonotic transmission awareness, low levels of education, the introduction of new animals and migration over large distances were found as common events that predispose to human–animal and animal–animal infection. In our study, a much higher proportion of households interviewed (48/83) indicated the presence of respiratory disease symptomatic of TB compared to a study where 2.3% was reported (Ghebremariam et al., 2018). This could be due to differences in sample size as well as stigma attached to being presumed to have TB which was also encountered in our study.…”

Genetic profiling of Mycobacterium bovis strains from slaughtered cattle in Eritrea

“…The samples were collected from one slaughterhouse and were few due to the absence of tissues with TBL during the study period. The low prevalence of BTB in the traditional livestock raising system [ 59 ] where majority of slaughtered animals come from, has limited the possibility of detecting more M . bovis strains from different geographical regions of Eritrea.…”

Prevalence of bovine tuberculosis in dairy cattle in China during 2010–2019: A systematic review and meta-analysis

“…It is well known that bTB can be transmitted through the respiratory tract, which is exacerbated by the closure of cattle sheds on scale farms, and higher stocking density also tends to be associated with regional epidemic of bTB [28]. The relatively high levels of sunlight outside, lower farming density, and better air circulation in free-range cattle reduce the burden of M. bovis, relative to that in scale farming [29]. In recent years, mass movement of dairy cattle between large-scale farms in China and the introduction of foreign cattle breeds may also accelerate the spread of bTB [30].…”