Serospatial epidemiology of zoonotic Coxiella burnetii in a cross section of cattle and small ruminants in northern Nigeria

Abstract

The persistent and highly transmissible Coxiella burnetii is a neglected infection that negatively affects reproductive parameters of livestock. It is also of zoonotic importance and has been reported to cause devastating human infections globally. Domestic ruminants represent the most frequent source of human infection. Data from Nigeria are very few and outdated. There is a significant gap in up-to-date information on the exposure, spatial distribution and risk factors of infection of this important disease. The exposure to C. burnetii was determined using sensitive serological assays in cattle and small ruminants. A total of 538 animals made up of 268 cattle and 270 small ruminants were sampled from three northern Nigerian states. The proportion of cattle sampled that were seropositive from the study locations were: Kwara 14/90 (15.6%; 95% CI: 8.8-24.7); Plateau 10/106 (9.43%; 95% CI: 4.6-16.7) and Borno 4/72 (5.56%; 95% CI: 1.5-13.6) states. Lower seroprevalence was recorded among the small ruminants sampled, with positives recorded from sheep and goat sampled from only Kwara state 6/184 (3.3%; 95% CI: 1.2-7.0); while none of the small ruminants sampled from Plateau were seropositive. The results of the bivariate analysis showed that none of the tested independent variables (village, age group, sex, breed of cattle, presence of ticks, reproductive status, and management system) were statistically significant factors associated with seropositivity of cattle for antibodies to C. burnetii. Stakeholders involved in animal husbandry should be duly educated on proper disposal of birth products as well as bodily fluids in order to reduce environmental contamination, persistence and human infection.

Fig 1. Map of Nigeria (within West Africa), showing the three northern states (Kwara, Plateau and Borno) where cattle and small ruminants were sampled.

Fig 2. Map of villages sampled in Kwara State showing the proportion of cattle seropositive for Coxiella burnetii.

Fig 3. Map of villages sampled in Plateau State showing the proportion of cattle seropositive for Coxiella burnetii.

Fig 4. Map of Borno State showing the proportion of cattle seropositive for Coxiella burnetii Coxiella burnetii seropositivity.