Oakley, Regina Bina, Gemechu, Gizachew, Gebregiorgis, Ashenafi, Alemu, Ayinalem, Zinsstag, Jakob, Paris, Daniel Henry, and Tschopp, Rea
Background: Coxiella burnetii, the causative agent of Q fever, and Rift Valley fever virus are two under-researched zoonotic pathogens in Ethiopia. Potential outbreaks of these diseases, in light of the high dependency of nomadic pastoralists on their livestock, poses a risk to both human and animal health in addition to risking the pastoralists livelihoods. Our study aimed to determine the seroprevalence and associated risk factors for Q fever and Rift Valley fever in pastoral communities in the Afar region of north-eastern Ethiopia. Methodology/Principal findings: This cross-sectional study screened pastoralists (n = 323) and their livestock (n = 1377) for IgG antibodies to Coxiella burnetii and Rift Valley fever virus. A seroprevalence for Q fever of 25.0% (95%CI 18.6–32.6) was found in pastoralists and 34.3% (95%CI 27.9–41.3) in livestock overall; with 51.9% in goats (95%CI 44.9–58.8), 39.9% in sheep (95%CI 24.6–51.2), 16.3% in camels (95%CI 10.4–24.6) and 8.8% in cattle (95%CI 5.0–15.0). For Rift Valley fever the seroprevalence in pastoralists was 6.1% (95%CI 3.3–11.0) and 3.9% (95%CI 2.6–5.7) in livestock overall; cattle had the highest seroprevalence (8.3%, 95%CI 3.3–19.2), followed by goats (2.7%; 95%CI 1.4–5.1), sheep (2.5%; 95%CI 1.0–5.9) and camels (1.8%; 95%CI 0.4–6.9). Human Q fever seropositivity was found to be associated with goat abortions (OR = 2.11, 95%CI 1.18–3.78, p = 0.011), while Rift Valley fever seropositivity in livestock was found to be associated with cattle abortions (OR = 2.52, 95%CI 1.05–6.08, p = 0.039). Conclusions/Significance: This study provides evidence for a notable exposure to both Q fever and Rift Valley fever in pastoralists and livestock in Afar. The outbreak potential of these pathogens warrants ongoing integrated human and animal surveillance requiring close collaboration of the human and animal health sectors with community representatives following a One Health approach. Author summary: Q fever and Rift Valley fever are two diseases that can affect both humans and animals, causing illness and death. These two diseases can cause large-scale outbreaks, not only affecting the health of individuals and communities but also resulting in a substantial economic loss at the individual, community, regional and national levels through losses in livestock products. We conducted a sero-epidemiological study in the Afar region of north-eastern Ethiopia to determine the presence of these two diseases in nomadic pastoralists and their livestock. Our results indicate that 25.0% of the pastoralists and 34.3% of their animals have had previous exposure to Q fever and 6.1% of the pastoralists and 3.9% of their animals have been exposed to Rift Valley fever. Goats appear to be the most common livestock species associated with Q fever in this region, while cattle are the most common species associated with Rift Valley fever. Our findings highlight the importance of continuous surveillance; additionally, we would recommend the development of rapid response plans for potential outbreaks that integrate the human and animal health sectors. [ABSTRACT FROM AUTHOR]