Coxiella burnetii Seroprevalence in Small Ruminants in The Gambia

Abstract

BackgroundQ fever is a zoonosis caused by Coxiella burnetii, a Gram negative bacterium present worldwide. Small ruminants are considered the main reservoirs for infection of humans. This study aimed to estimate the extent of C. burnetii infection among sheep and goats in part of The Gambia.Methodology/Principal FindingsThis survey was carried out from March to May 2012 at two areas in The Gambia. The first area comprised a cluster of seven rural villages situated 5–15 km west of Farafenni as well as the local abattoir. A second sampling was done at the central abattoir in Abuko (30 km from the capital, Banjul) in the Western Region. Serum samples were obtained from 490 goats and 398 sheep. In addition, 67 milk samples were obtained from lactating dams. Sera were tested with a Q fever ELISA kit. C. burnetii DNA was extracted from milk samples and then detected using a specific quantitative multiplex PCR assay, targeting the IS1111a element. A multivariable mixed logistic regression model was used to examine the relationship between seropositivity and explanatory variables. An overall seroprevalence of 21.6% was found. Goats had a significantly higher seroprevalence than sheep, respectively 24.2% and 18.5%. Seropositive animals were significantly older than seronegative animals. Animals from the villages had a significantly lower seroprevalence than animals from the central abattoir (15.1% versus 29.1%). C. burnetii DNA was detected in 2 out of 67 milk samples, whereas 8 samples gave a doubtful result.Conclusion/SignificanceA substantial C. burnetii seroprevalence in sheep and goats in The Gambia was demonstrated. People living in close proximity to small ruminants are exposed to C. burnetii. Q fever should be considered as a possible cause of acute febrile illness in humans in The Gambia. Future studies should include a simultaneous assessment of veterinary and human serology, and include aetiology of febrile illness in local clinics.

Occurrence and Genotyping of Coxiella burnetii in Ixodid Ticks in Oromia, Ethiopia

“…16 Included in the few studies from African countries are reports of antibodies against C. burnetii in the sera of 1-24% of humans in 7 west African countries: 17 30.9% of humans, 28.3% of cattle, 18.2% of sheep and 32% of goats in Kenya, 18 24.2% of goats and 18.5% of sheep in Gambia, 19 C. burnetii DNA in the blood of 7.8% of cattle and 7.5% of goats in Tanzania, 20 and 0.3% of febrile patients in Algeria and 0.4% in Senegal 21 . A previous study performed nearly half a century ago in Ethiopia reported the detection of C. burnetii in 5.3% of Amblyomma variegatum and 10.8% of Hyalomma truncatum ticks.…”

Coxiella burnetii(Q Fever) Infection in Farmed Ruminants in Three Northeastern Provinces and Inner Mongolia Autonomous Region, China

“…Moreover, subclinical infection in carrier animals is typical (Saegerman et al 2015). Serological methods, such as immunofluorescence assay (IFA) and ELISA, have been widely used for Q fever diagnosis (Ni et al 2011, González-Barrio et al 2013, Klaasen et al 2014, Shin et al 2014. We used the ELISA method because of its convenience and high sensitivity.…”

“…Humans are infected primarily by inhaling an aerosol contaminated with material from the urine or feces of infected animals (Esmaeili et al 2014, Schimmer et al 2014. People engaged in livestock breeding have a particularly high seroprevalence (Guatteo et al 2011, Klaasen et al 2014. Ticks are the main reservoir hosts, but mammals, birds, and other arthropods also play an important role in transmission (Ioannou et al 2009).…”

“…In animals, C. burnetii infection is usually mild with no distinct clinical signs. However, it is likely associated with infertility in cattle and late abortions in small ruminants (goats and sheep) (Klaasen et al 2014). Analysis of recent human Q fever outbreaks suggests that small ruminants, such as sheep and goats, play an important role in these outbreaks, rather than cattle (Georgiev et al 2013).…”

“…This is because of the massive shedding by small ruminants of C. burnetii during abortions. Thus, detecting the shedders of C. burnetii and investigating the prevalence of the infection are important for controlling the transmission of C. burnetii among animals and from animals to humans (Maurin and Raoult 1999, Cardinale et al 2014, Klaasen et al 2014.…”