[Soil properties and microbial respiration activities of riparian forest wetland in the north of permafrost zone, the Great Hing'an Mountains, Northeast China]. / å¤§å ´å®‰å²­åŒ—éƒ¨å¤šå¹´å†»åœŸåŒºæ²³å²¸æ£®æž—æ¹¿åœ°åœŸå£¤æ€§è´¨å’Œå¾®ç”Ÿç‰©å‘¼å¸æ´»æ€§ç‰¹å¾.

Riparian wetlands in permafrost regions are critical regions for hydrological, ecological, and biochemical processes. We studied the soils of riparian and transition wetlands and analyzed physicochemical properties, stoichiometry, and microbial respiration activities (microbial biomass carbon, basal respiration, microbial entropy, and metabolic entropy) of the humus layer and diffe-rent soil layers. The results showed that the main differentiation of soil physical and chemical pro-perties in riparian forest wetlands was below 20 cm. Compared to the wetlands of transition zone, total carbon content, total nitrogen content, C/P and N/P decreased significantly with soil depth in riparian forest wetlands. These changes in soil stoichiometry were mainly caused by soil nitrogen content. Such a result meant that the transferring of nitrogen was relatively fast and that there was nitrogen limitation. The main differentiation of Na, Mg, K and Ca in soil occurred in the 30 cm layer of the transition zone and the 20 cm layer of the riparian forest wetlands. The correlations between soil Mg content and total C, total N, total P contents were significant. It meant that the soil Mg was an important element to riparian wetlands in the Great Hing'an Mountains. Microbial respiration activities of the humus layer in riparian forest wetlands and transition zone were higher than those in the other soil layers, indicating that the content of labile carbon fractions was high. The correlations between soil microbial respiration activities and soil properties, stoichiometry, nutrient elements were different in riparian wetland and transition zone. Soil total nitrogen contents were significantly correlated with soil microbial respiration activities in riparian wetland, indicating that soil microbial respiration activities were limited by nitrogen in riparian wetland of the Great Hing'an Mountains.

Risk Factors for Bunyavirus-Associated Severe Fever with Thrombocytopenia Syndrome: A Community-Based Case-Control Study.

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by a novel bunyavirus. Previous studies about risk factors for SFTSV infection have yielded inconsistent results, and behavior factors have not been fully clarified. METHODS: A community-based, 1:4 matched case-control study was carried out to investigate the risk factors for SFTS in China. Cases of SFTS were defined as laboratory-confirmed cases that tested positive for real-time PCR (RT-PCR) for severe fever with thrombocytopenia syndrome bunyavirus (SFTSV) or positive for IgM antibodies against SFTSV. Controls of four neighborhood subjects were selected by matching for sex, age, and occupation. Standardized questionnaires were used to collect detailed information about their demographics and risk factors for SFTSV infection. RESULTS: A total of 334 subjects participated in the study including 69 cases and 265 controls. The median age of the cases was 59.5 years, 55.1% were male, and 87.0% were farmers. No differences in demographics were observed between cases and controls. In the final multivariate analysis, tick bites two weeks prior to disease onset (OR = 8.04, 95%CI 3.34-19.37) and the presence of weeds and shrubs around the house (OR = 3.46, 95%CI 0.96-12.46) were found to be risk factors for SFTSV infection; taking preventative measures during outdoor activities (OR = 0.12, 95%CI 0.01-1.01) provided greater protection from SFTSV infection. CONCLUSIONS: Our results further confirm that SFTSV is transmitted by tick bites and prove that preventative measures that reduce exposure to ticks can prevent SFTSV infection. More efforts should be directed toward health education and behavior change for high-risk populations, especially outdoor workers, in SFTS endemic areas.

[A cross-sectional survey on the prevalence of Brucellosis among workers in Jiangsu province, 2012].

OBJECTIVE: To study the status of infection and risk factors on Brucellosis among workers in Jiangsu province so as to provide related preventive and control measures. METHODS: A cross-sectional survey was conducted on 238 workers at three butcheries, one trading market and one stockyard. Related risk factors on the different exposures to the disease were also analyzed. RESULTS: 50 workers were identified to have had the infection, with a infection rate as 21% (50/238). No significant differences in gender, age, working length and occupations were found. Jobs as slaughtering (RR = 1.80, 95%CI:1.1-3.1), particular on bleeding (RR = 1.90, 95%CI:1.1-3.3) were risk factors. Habit as hand-washing before eating was a protective factor (RR = 0.25, 95% CI: 0.14-0.44). CONCLUSION: Workers from butcheries, trading markets and stockyards were seriously infected with Brucellosis in Jiangsu province and related. Control measures and education should be implemented to the workers in that trade.

[Surveillance of echinococcosis in high risk areas of Yixing City from 2008 to 2009].

An investigation was conducted retrospectively for echinococcosis (hydatid disease) in Yixing City from 2008 to 2009, the serum or fecal samples of suspected patients during the past 5 years and host animals were assessed by ELISA. There were 2 cases reported by network and 4 confirmed patients by investigation, and among the total 6 cases, 5 cases may be infected in the locality. The positive rates were 0.52%, 0.14% and 1.08% in adults aged over 20 years, children aged 7 to 12 years (by serum tests) and dogs (by fecal tests) respectively.