Molecular Detection and Risk Factors Analysis of Coxiella Burnetii and Chlamydia Abortus Infections in Sheep and Goats in Kajiado, Kenya

Abstract

Chlamydia abortus (C. abortus) infection and Q fever caused by Coxiella burnetii (C. brunetii) are zoonotic diseases caused by obligate intracellular bacteria. The infections cause economic losses in sheep and goat production systems in many parts of the world. The diseases are also of public health importance since they can infect humans. Information on the status of the two infections and risk factors responsible for the outbreak infections in sheep and goats is limited or lacking in Kenya, especially in pastoral communities. Moreover, molecular detection for confirming infections in shoats has not been exploited widely in Kenya. As a consequence, the objective of this study was to investigate into the presence of Q-fever and C. abortus infection in sheep and goats in five selected wards in Kajiado County. One hundred and thirty pastoralist flocks were selected from the five wards, which included Ildamat (27 flocks), Iloodokilani (27 flocks), Matapato south (25 flocks), Kenyawa-Poka (21 flocks), and Kaputiei north (30 flocks). After that, 1560 sheep and goat blood samples were collected from these flocks in the five wards. The samples were then transported to the Department of Public health, Pharmacology Laboratory for further analysis. The genomic DNA was extracted from whole blood samples using the Gene JET commercial Mini-Kit according to the manufacturer's instructions. Oligonucleotide primer targeting IS1111transposase element of C. brunetti and 16S-23S rRNA of C. abortus was used to amplify the DNAs by polymerase chain reaction (PCR) using the Veriti 96 well thermos-cycler. The amplicons were electrophoresed, stained, and visualized by a gel documentation imager. To assess the risk factors as well as to establish knowledge, attitudes, and practices of the pastoralist farmers, questionnaires were administered to respondents responsible for the flock. The prevalence of the two infections was estimated, and risk factors were determined by logistic regression. Coxiella burnetti-DNA was not detected in all samples analyzed. Chlamydia

abortus DNA was detected in 86 (24.8%) sheep and goats blood samples, with 30(20.3%) samples being detected in sheep while 56 (28.1%) samples were detected in goats. Although samples positive for C. abortus-DNA were more in goats than those in sheep, the difference observed was not statistically significant (P <0.0.5). The prevalence of C. abortus in the five wards was 34.96% in Ildamat, 31.6% in Iloodokilani, 10.9% in Mathapato south 15.4% in Kenyawa poka, and 18.4% in Kaputiei. Approximately 56% of the farmers reported abortions as the main problem in their flocks. They believed that infections such as Brucellosis, Rift valley fever, tick-borne diseases were the major problems in their flocks. The study also found that 27.7% of the respondents were aware of zoonotic diseases. Furthermore, it was also observed that 39 (30%) farmers were aware that some of these diseases could also be transmitted to humans through the consumption of milk and meat. The risk factors associated with C. abortus infection were the watering points for animals during the wet season (OR=1.57, P=0.02), abortions (OR.84, P=0.02), and consumption of fermented raw milk by household pastoralists (OR=1.25, P= 0.05). In conclusion, it appears that sheep and goats raised in Kajiado County are infected with C. abortus. Transmission of C. abortus may be enhanced by overcrowding of sheep and goats at a drinking point during the wet season, as well as abortion in flocks. Further research on detection and risk factors of the two infections among pastoralists is recommended.