Molecular Detection of Coxiella burnetii from Farm Animals and Ticks in Malaysia.

Coxiella burnetii, the causative agent of Q fever, is an intracellular bacterium of medical and veterinary importance. The reservoirs of C. burnetii are extensive which include mammals and arthropods, particularly ticks. As the organism is difficult to culture, this study was aimed to detect C. burnetii DNA in animal (mainly blood and vaginal samples of cattle, goats and sheep) and tick samples obtained from farm animals, wild rodents and vegetation. Two polymerase chain reaction (PCR) assays targeting IS1111 transposon-like gene (TransPCR) and com1 gene (OMP-PCR) were used for C. burnetii detection. Sequence determination of the amplified fragments and a real-time PCR assay were used to confirm PCR findings. C. burnetii DNA was detected from 9.1% of cattle blood and 4.2% vaginal samples, respectively. A small percentage (5.8%) of ticks (including Amblyomma, Dermacentor, Rhipicephalus and Haemaphysalis spp.) haboring C. burnetii were identified in this study. This study provides molecular evidence on the presence of C. burnetii in cattle and ticks. The possible zoonotic transmission of C. burnetii is yet to be investigated.

Case-control investigation on the risk factors of melioidosis in small ruminant farms in Peninsular Malaysia.

AIMS: Epidemiology of melioidosis is poorly understood because its occurrence is influenced by complex interaction of environmental, climatic, physicochemical and host factors. We investigated the potential risk factors for the exposure to Burkholderia pseudomallei in small ruminants' farms in Peninsular Malaysia. METHODS AND RESULTS: Melioidosis-positive (n = 33) and negative (n = 27) farms were selected and visited for interviews and environmental samples collection. The characteristics and putative disease risk factors were compared between the case and the control farms using Chi-square test and logistic regression analysis. The multivariable logistic regression analysis showed that the odds of melioidosis were significantly higher in farms that had bush clearing around farms (odds ratio (OR) = 6.61, 95% confidence interval (CI) = 1.12-38.84, P = 0.037), in farms with B. pseudomallei present in the soil (OR = 6.23, 95% CI = 1.03-37.68, P = 0.046), in farms that have other animal species present (OR = 7.96, 95% CI = 1.14-55.99, P = 0.037) and in farms that had flooding or waterlogging conditions (OR = 11.95, 95% CI = 1.39-102.6, P = 0.024) when compared to the odds of the disease in farms that did not have the above conditions. The odds of the disease in farms that treated their soils with lime were significantly lower (OR = 0.028, 95% CI = 0.003-0.29, P = 0.003) compared to the odds in those that did not. CONCLUSIONS: The risk factors for the exposure to B. pseudomallei highlighted above may have contributed to the occurrence of melioidosis in animals in the study farms. SIGNIFICANCE AND IMPACT OF THE STUDY: Information from the study may be helpful in planning control measures against melioidosis and have improved understanding of the epidemiology of the disease in livestock farms.

Inter-species differentiation of benign Theilerias by genomic fingerprinting with arbitrary primers.

A method was developed to obtain reproducible DNA fingerprints from five distinct purified benign Theileria genomic DNAs by PCR-based amplification. Randomly amplified polymorphic DNA (RAPD) profiles were obtained from 10 randomly designed 12-mers. However, nine of the 10 primers could generate the difference in RAPD-PCR profiles which allowed discrimination of Theileria species. The method has advantage of being simple, fast and sensitive for diagnosis and characterization of the parasites since it does not require prior DNA sequence information to construct species-specific probes or primers. The results are also beneficial for a proper understanding of the epidemiology and designing rational control programmes for Theileriosis in Asian and South-East Asian countries.