Lyme Borreliosis-associated Risk Factors in Residents of Beijing Suburbs: a Preliminary Case-control Study / 生物医学与环境科学（英文）

A population-based case-control study was conducted to evaluate the relative factors in the environments, agricultural works, outdoor activities, and the effectiveness of Lyme borreliosis (LB)- associated personal protective measures in Beijing. Thirty-four cases and 272 controls were personally interviewed by well-trained interviewers. Venous blood samples were taken from each subject. Sowing or harvesting in summer (OR=2.571, 95% CI: 1.109-5.962), living in house with weeding in the yard (OR=2.247, 95% CI: 1.062-4.755), and residence at the plain area (OR=2.630, 95% CI: 1.050-6.588) were the independent relative factors for seropositive LB. Wearing long pants and clothes with cuffs was the only protective behavior against tick bite (OR=0.186, 95% CI: 0.041-0.846). The findings showed that local farmers were easily infected with LB and almost no protective measure was taken against LB infection. Infection with LB was easier in residents of plain regions. Pets raising and outdoor activities were not the risk factors for infection with LB. Further studies are needed to fully understand the risk of infection with LB in China.

Investigation on Ehrlichia chaffeensis and Anaplasma phagocytophilum infection among farmers and domestic animals in rural areas of Beijing, China / 中华流行病学杂志

Objective To investigate the status of Ehrlichia (E.)chaffeensis and A naplasma (A.) phagocytophilum infection among farming populations and domestic animals in the rural area of Beijing,China.Methods Blood samples from 562 farmers and 163 blood samples including 90 goats,71 ox and 2 dogs,were collected.Specificity of IgG antibodies against E.chaffeensis and A.phagocytophilum were tested by micro-indirect immunofluorescent assay (mIFA).16S rRNA genes of A.phagocytophilum were amplified from the domestic animal blood samples and products were sequenced and analyzed by nested PCR.Results The positive rates of E.chaffeensis and A.phagocytophilum antibody were 16.5％ and 14.0％ respectively for farmers.The total positive rates of A.phagocytophilum were 2.3％ and 0 for both goats and oxen respectively.No antibody was found for the 2 tested dogs.The PCR positive rates were 48.9％ and 23.9％ for goats and oxen respectively.Three dominant varieties of A.phagocytophilum were demonstrated in goats and oxen.Conclusion The prevalence rates of E.chaffeensis and A.phagocytophilum were identified in the rural areas of Beijing.