Serosurvey and Risk Factors of Coxiella burnetii in Sheep and Goats in three agricultural zones of Borno State, Nigeria

Abstract

Coxiellosis (Q-fever) caused by Coxiella burnetii is a cosmopolitan zoonosis that causes significant losses through abortions and stillbirths in small ruminants. A cross-sectional seroprevalence study was conducted in three agricultural zones of Borno State in the flocks of sheep and goats. Seven hundred sixty-eight small ruminants (384 sheep and goats each) of both sexes (282 males and 486 females) of different age groups from 90 flocks were randomly selected to collect sera and related epidemiological data information. A commercial indirect enzyme-linked immunosorbent assay (iELISA; I.D. Vet) was used to test the samples for the presence of both phases I and II antibodies to Coxiella burnetii infections. The seroprevalence in sheep and goats was 10.9% (44/384) and 12.0% (46/384). There was no statistically significant association in the two species of the animals tested and the infection rates of coxiellosis. Bivariate analysis showed that female animals of all species tested were more seropositive for antibodies to Coxiella burnetii than males. There was a statistically significant association between the sex of both sheep and goats tested and the infection rates of coxiellosis. Breed and age of sheep and goats were not statistically significant for seropositivity to Coxiella burnetii. The study indicates that seroprevalence of coxiellosis was high in the studied small ruminants’ population, particularly among female sheep and goats and can be considered a potential risk for both susceptible animals and humans in the study area.

Distribution and Prevalence of Coxiella burnetii in Animals, Humans, and Ticks in Nigeria: A Systematic Review

“…All these observations point to the role of milk as a vehicle in the transmission of C. burnetii to humans. In our study, we also observed that among small ruminants, the infection rates for sheep was comparatively higher at 3.8-12.0% [3,26], compared to goats at 3.1-10.9% [3,25,31,32]. On the contrary, the infection rate in a similar study in Kenya showed that the infection was higher in goats (20.0-46.0%) compared to sheep (6.7-20.0%), while the results for other host includes cattle (7.4-51.0%) and camels (20.0-46.0%) [49].…”

“…The features of all the studies included in this review are summarized in Table 1. The studies included in this review used either an Enzyme-Linked Immunosorbent Assay (ELISA) [3,[25][26][27][28][29][30][31][32][33] or a Microimmunofluorescence test [23] to carry out serological analysis or molecular assays [14][15][16]22] for the detection of C. burnetii. The Capillary Agglutination Test (CAT) was also employed to screen the milk samples for C. burnetii [34].…”

“…Similarly, only one study in southern Nigeria screened ticks' DNA for C. burnetii compared to two studies in the north. However, across Nigeria, the prevalence of C. burnetii in cattle ranges from 2.5 to 23.5% [3,25,[31][32][33]; for sheep, it ranges from 3.8 to 12.0% [3,26]; and for goats, from 3.1 to 10.9% [3,25,31]. The result for human-reported prevalence ranges are from 12.0 to 61.3% [25,32].…”

“…A combination of several diagnostic methods has been employed so far, including the capillary agglutination test (CAT) [34], the Enzyme-Linked Immunosorbent Assay (ELISA) [3,[25][26][27][28][29][30][31][32][33], and PCR [14][15][16]22] for the study of coxiellosis in humans, animals, milk, and tick vectors in the country. However, the studies involving tick species employed morphological identification of tick species and semi-nested PCR, which was used to detect the genetic materials of C. burnetii from the vectors targeting the 16S rDNA gene [16].…”

“…The majority of the published studies on C. burnetii infection in humans, animals, and tick vectors were observed to have emanated from the northern region of the country with prevalence ranging from 3.8 to 11.9% [3,[25][26][27][28][29][30][31][32]. The present study identified two PCR-based studies that examined the presence of C. burnetii DNA in ticks in the northern part of Nigeria.…”