Rift Valley fever (RVF) is an emerging and re-emerging mosquito-borne zoonosis of major economic, public health, and veterinary importance, often causing great population-level impact. Q fever remains a neglected zoonotic disease of considerable public health and veterinary significance, responsible for notable economic losses for livestock farmers. Despite their significance, the epidemiology of RVFV and Coxiella burnetii (Q fever) remains poorly understood, with little evidence on their seroprevalence and associated risk factors. We conducted a cross-sectional study to estimate the seroprevalence of RVFV and C. burnetii, and to identify associated risk factors in domestic livestock. We collected a total of 568 blood samples from domestic livestock across three different districts using convenience sampling. Individual animal and herd-level data were obtained through a pre-tested structured questionnaire. Serum samples were tested for antibodies against RVFV and C. burnetii using a competitive Enzyme-Linked Immunosorbent Assay (cELISA). While none of the animals tested positive for RVFV antibodies, the overall seroprevalence of C. burnetii antibodies was 9.7% (95% CI: 7.4-12.4), which was highest in sheep (5.8%), followed by goats (2.1%), camels (1.1%), and cattle (0.7%). Animals from households (OR = 0.19, p = 0.04) and young livestock (OR = 0.10, p burnetii seropositivity than those from farms and adults, respectively, whereas animals with moderate BCS (OR = 3.1, p burnetii among livestock population of this country. Although no serological evidence of RVFV was detected in the studied animals, the possibility of exotic vector-borne disease being introduced into the country cannot be ruled out. Therefore, we recommended establishing a sustainable surveillance program in both livestock and vector populations to monitor and mitigate the burden of Q fever while maintaining vigilant for potential RVF emergence and other vector-borne viruses in regions where they are not currently endemic at the animal-human interface.
Rural communities in Malaysia have been shown to be exposed to Coxiella, Borrelia and rickettsial infections in previous seroprevalence studies. Further research is necessary to identify the actual causative agents and the potential vectors of these infections. The arthropods parasitizing peri-domestic animals in these communities may serve as the vector in transmitting arthropod-borne and zoonotic agents to the humans. Molecular screening of bacterial and zoonotic pathogens from ticks and fleas collected from dogs, cats and chickens from six rural communities in Malaysia was undertaken. These communities were made up of mainly the indigenous people of Malaysia, known as the Orang Asli, as well as settlers in oil palm plantations. The presence of Coxiella burnetii, Borrelia, and rickettsial agents, including Rickettsia and Anaplasma, was investigated by performing polymerase chain reaction (PCR) and DNA sequencing. Candidatus Rickettsia senegalensis was detected in one out of eight pools of Ctenocephalides felis fleas. A relapsing fever group Borrelia sp. was identified from one of seven Haemaphysalis hystricis ticks tested. The results from the PCR screening for Anaplasma unexpectedly revealed the presence of Candidatus Midichloria sp., a potential tick endosymbiont, in two out of fourteen Haemaphysalis wellingtoni ticks tested. C. burnetii was not detected in any of the samples tested. The findings here provide evidence for the presence of potentially novel strains of rickettsial and borrelial agents in which their impact on public health risks among the rural communities in Malaysia merit further investigation. The detection of a potential endosymbiont of ticks also suggest that the presence of tick endosymbionts in the region is not fully explored.
A total of 44 Rhipicephalus sanguineus ticks collected from 23 dogs from Malaysia were screened for Rickettsia, Anaplasmataceae and Coxiella burnetii. Coxiella burnetii was detected in 59% (26/44) of ticks however Rickettsia and Anaplasmataceae were not detected in any of the ticks. In order to genotype the strains of C. burnetii, multispacer sequence typing (MST) was carried out using three different spacers. One of the spacers; Cox2 successfully amplified a fragment for which the full length sequence of 397 bp was obtained. The sequenced product revealed only a single nucleotide difference with the Cox2.3 type sequence.