ABSTRACT
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.
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Agriculture , Case-Control Studies , China , Epidemiology , Cities , Environment , Human Activities , Lyme Disease , Epidemiology , Microbiology , Risk FactorsABSTRACT
Objective To understand the exposure and the infection status of virus among people engaging in breeding or butchering ducks in the suburb of Beijing.Methods People from six districts (Daxing,Fangshan,Huairou,Miyun,Shunyi,Tongzhou) who engaged in breeding or butchering ducks were studied and the status of infecting avian influenza virus was obtained by testing antibody level in serum.Information on demographic characteristics,status of regular exposure and exposure to sick or dead poultry were collected through a self-designed questionnaire.Results 1741people were involved in this study in which 313 (18.0％ ) were workers in duck-breeding enterprise,562 (32.3％) were workers in duck slaughterhouse,261 (15.0％) farmers were in individualsmall-scale duck farms,605 (34.7％) were farmers raising duck in backyard.Among farmers raising duck in backyard,the percentage of people whose ducks ever contacted with wild birds was higher than the other three groups (66.8％)(P＜0.05).Among farmers who bred their ducks in the backyard (35.2％) and those abattoir workers (31.3％ ),the percentage of people who had contacted ducks but not been vaccinated with avian influenza vaccine was higher than the other two groups (P＜0.05).Regarding the status on cleaning and disinfection among the studied farmers who had bred their ducks in the backyard,the percentage of people who had closer contact with ducks would clean the settings more than 4 times per month (8.8％) and disinfected those places more than 12 times per year (27.3％) but still lower than the other three groups (P＜0.05).Among those farmers who bred ducks in the backyard,the percentage of people who had ever touched duck with their hands was high (34.4％) (P＜ 0.05).Regarding exposure to sick or dead poultry,higher proportion was found among those who had ever closely contacted sick or dead poultry commercial duck raisers (36.1％) and individuals who raise large amount of ducks (36.0％).70.8％ of the individual duck raisers had never taken any protective measures when closely contacting the sick or dead poultry.Among 1741 samples,0 were positive to avian influenza virus H5 and H7 subtypes.12 were positive to H9 subtype (positive rate was 0.7％ ),in which 10 were farmers raising ducks in backyard (the positive rate of 1.7％ ).Differences between H9 subtype antibody positive rates difference in 4 population groups were statistically significant (x2=13.699,P＜0.05).Conclusion Farmers who bred their ducks in the backyard had greater risk of contracting the avian influenza.Individual duckers who raise ducks in large scale and the farmers who bred their ducks in the backyard were in lack of protective measures when contacting the sick or dead poultry.Our findings suggested that some intervention measures should be taken to reduce the risk of avian influenza infection.
ABSTRACT
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.