The prevalence of brucellosis and bovine tuberculosis in ruminants in Sidi Kacem Province, Morocco

Abstract

Bovine tuberculosis (BTB) and brucellosis are major endemic zoonoses in ruminants in Morocco that impact on both animal and human health. This study presents an assessment of the epidemiological and socioeconomic burden of bacterial zoonoses in Sidi Kacem Province in Northern Morocco from a cross-sectional survey of 125 cattle and/or small ruminant-owning households. In total, 1082 sheep and goats were examined from 81 households. The single intradermal comparative cervical test to screen for bovine tuberculosis was undertaken on 1194 cattle from 123 households and all cattle were blood sampled. Cattle and small ruminant sera were tested for brucellosis using the standard Rose Bengal Test (sRBT) and the modified Rose Bengal Test (mRBT). Bacteriology was performed on 21 milk samples obtained from cattle that were seropositive for brucellosis for isolation and phenotyping of circulating Brucella strains. Individual and herd prevalence for BTB in cattle of 20.4% (95% CI 18%-23%) and 57.7% (95% CI 48%-66%), respectively, were observed in this study. The prevalence of brucellosis in cattle at individual and herd level was 1.9% (95% CI 1.2%-2.8%) and 9% (95% CI 4.5%-1.5%), respectively. Brucella pathogens were isolated from three cattle milk samples and were identified as B. abortus using Bruceladder® multiplex PCR and B. abortus biovar 1 by classical phenotyping. All small ruminants were seronegative to sRBT, two were positive to mRBT. A higher risk of BTB and brucellosis was observed in cattle in intensive livestock systems, in imported and crossed breeds and in animals from larger herds (>15). The three risk factors were usually present in the same herds, leading to higher transmission risk and persistence of both zoonoses. These results highlight the importance of implementing control strategies for both BTB and brucellosis to reduce productivity losses and the risk of transmission to humans. Prioritising control for BTB and brucellosis in intensive livestock production systems is essential for human and animal health.

Bovine tuberculosis prevalence and risk factors in selected districts of Bangladesh

“…In view of the financial losses caused by bTB and in addition to its public health risk, further efforts should be made to implement a science based disease control strategy. Test and slaughter has been presented as the best strategy to eliminate bTB in high income countries around the world [ 63 ]. However, due to socio-economic reasons such a strategy is not easily implementable in LMICs such as Bangladesh.…”

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

“…Intensive farming has been shown to be a contributing factor to bTB in animals [14,27]. 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 the seasonal subgroup, the prevalence in summer was significantly higher than in winter (P < 0.05). Cattle are more stressed in the hotter and wetter summer months [28,31]. In addition, the days are longer than the nights in summer, giving cows that are active for a prolonged time more opportunity to come into contact with sick animals [34].…”

“…The results were basically consistent with the above seasonal and geographical factors. We speculated that warm and humid weather may exacerbate the prevalence of bTB [28,29,31].…”

Interactive web-based tool for evaluating the spread of bovine tuberculosis and brucellosis in Colombia

“…We suggest that BTB and brucellosis are spreading actively since 2004 in temporal outbreaks, which can be explained by low screening and lack of suitable detection tools (Henrioud, 2011;Arenas et al, 2017). The main causes that influence the active spread of BTB and brucellosis in Colombia could be attributable to illegal animal traffic from neighboring countries, deficiencies in intensive testing plans, lack of socio-economic benefits and trade-offs for smallholder milk farmers with positive animals, and animal movement or insemination procedures between non-certified livestock farms (Jojoa-Jojoa et al, 2016;Yahyaoui-Azami et al, 2018;Ávila-Granados et al, 2019;Cárdenas et al, 2019). Remarkably, our dashboard can allow users to infer potential epidemiological links regarding BTB and brucellosis cases found in livestock production systems (Fletcher-Lartey and Caprarelli, 2016).…”