[Disease burden of chronic obstructive pulmonary diseases in China from 1990 to 2019].

Objective: To examine the trend of the burden on chronic obstructive pulmonary diseases (COPD) and epidemiologic transition on related risk factors among the Chinese population from 1990 to 2019. Methods: Based on the data from the Global Burden of Disease 2019 Study, we used the indicator numbers such as disability-adjusted life year (DALY), years of life lost (YLD), years lived with disability (YLL), and prevalence rate to describe the changes of COPD burden stratified by different sex and age groups from 1990 to 2019. We applied population attribution faction (PAF) to analyze the burden attributed to risk factors and epidemiological transition. Results: In 2019, the age-standard rate for DALY, YLD, and YLL and prevalence rate for COPD were 1 102.77/100 000 population,862.37/100 000 population, 240.40/100 000 population, and 2 404.41/100 000. Both age-standardized DALY and YLL rates for COPD in males were higher than in females, except for the YLD rate in females. COPD's top five risk factors were particulate matter pollution, smoking, occupational particulate matter, gases, and fumes, low temperature, and secondhand smoke. Smoking surpassed environmental particulate pollution in 1994 and became the first factor causing the disease burden of COPD. Since then, the order of risk factors has not changed. The PAF of environmental particulate pollutants increased by 1.78% annually, from 15.22% in 1990 to 25.37%, and the PAF of household air pollution from solid fuels decreased by 5.59% annually, from 40.30% in 1990 to 7.59%. Conclusions: From 1990 to 2019, the per person health loss caused by COPD in China showed an overall downward trend. The PAF of relevant risk factors has also changed, the importance of environmental factors is relatively declined, and the status of smoking and other related risk behaviors has become increasingly prominent. The prevention and control of COPD can focus on screening high-risk groups (≥40 years old, smoking, heavy air pollution, having occupational exposure), smoking cessation, and environmental treatment.

Assessment of community-wide antimicrobials usage in Eastern China using wastewater-based epidemiology.

Wastewater-based epidemiology (WBE) has potential to identify the epidemiological links between people, animals, and the environment, as part of antimicrobial resistance (AMR) surveillance. In this study, we investigated six wastewater treatment plants (WWTPs) serving six communities located in two regions in Eastern China: Site A in Zhejiang and site B in Jiangsu province to assess the public use of antimicrobial agents (AA). Fifty antimicrobials and 24 of their metabolites were quantified using ultraperformance liquid chromatography coupled with triple quadrupole tandem mass spectrometry (UPLC-MS/MS). Spatiotemporal trends were established for measured concentrations, daily loads, and population-normalised daily loads. Daily AA mass loads varied between 1.6 g/day and 324.6 g/day reflecting the WWTP scales, with macrolides and ß-lactams showing the highest overall environmental burden at 223.7 g/day and 173.7 g/day, respectively. Emissions of antibiotic residues from manufacturing have been observed, with the peak daily load 12-fold higher than the overall load from a community serving a population of over 600,000. Community exposure levels of 225.2 ± 156.2 mg/day/1000 inhabitant and 351.9 ± 133.5 mg/day/1000 inhabitant were recorded in site A and B, respectively. Paired parent-metabolites analysis identified a large proportion (64-78%) of un-metabolised metronidazole and clindamycin at site B, indicating improper disposal of unused drugs either in the community or in livestock production. Consumption levels, calculated via WBE, suggested relatively low antimicrobial usage in Eastern China compared to other areas in China. This first application of WBE in Eastern China to assess the community-wide exposure to AAs has potential to inform regional antimicrobial stewardship.

Inequalities in changing mortality and life expectancy in Jiading District, Shanghai, 2002-2018.

BACKGROUND: Improvements of population health in China have been unevenly distributed among different sexes and regions. Mortality Registration System provides an opportunity for timely assessments of mortality trend and inequalities. METHODS: Causes of death were reclassified following the method of Global Burden of Disease Study (GBD). Age-standardized mortality rate (ASMR) and ring-map of the rate by town were used to describe inequalities in changing mortality. Life expectancy (LE) and cause-deleted LE were calculated on the basis of life table technique. RESULTS: The burden of death from 2002 to 2018 was dominated by cardiovascular diseases (CVD), neoplasms, chronic respiratory diseases and injuries in Jiading district, accounting for almost 80% of total deaths. The overall ASMR dropped from 407.6/100000 to 227.1/100000, and LE increased from 77.86 years to 82.31 years. Women lived about 3.0-3.5 years longer than men. Besides, a cluster of lower LE was found for CVD in the southeast corner and one cluster for neoplasms in the southern corner of the district. The largest individual contributor to increment in LE was neoplasms, ranged from 2.41 to 3.63 years for males, and from 1.60 to 2.36 years for females. CONCLUSIONS: Improvement in health was mainly attributed to the decline of deaths caused by CVD and neoplasms, but was distributed with sex and town. This study served as a reflection of health inequality, is conducive to formulate localized health policies and measures.

Predictors, sources, and health risk of exposure to neonicotinoids in Chinese school children: A biomonitoring-based study.

BACKGROUND: Recent studies have suggested an extensive exposure to neonicotinoids in human, but the information on predictors, sources, and health risk remains limited in children. OBJECTIVE: To explore the predictors, sources, and health risk for exposure of Chinese school children to neonicotinoids by biomonitoring method. METHODS: In 2019, 309 school children aged 7-11 years were selected from a dynamic cohort of children established in Shanghai, East China. Eight neonicotinoids and four metabolites were determined in first morning urine. After detailed information on demographic and socioeconomic indices, intake of drinking water, food consumption, and anthropometric measurements was collected, the predictors and sources of exposure to neonicotinoids were explored by binary and ordinal logistic regression models. Health risk was assessed by the hazard quotient (HQ) and hazard index (HI) based on estimated daily exposure dose. RESULTS: Six neonicotinoids (thiamethoxam, clothianidin, imidacloprid, acetamiprid, nitenpyram, and dinotefuran) and three metabolites (N-desmethyl-thiamethoxam, N-desmethyl-clothianidin, and N-desmethyl-acetamiprid) were detected in 81.3% of urine samples. Children in nuclear family or girls had a higher detection frequency of thiamethoxam. N-desmethyl-acetamiprid was more likely to be detected in children who were older, physically active, or obese. Parents' occupation was heterogeneously associated with the detection of thiamethoxam and clothianidin. Thiamethoxam and clothianidin were more likely to be detected in children consuming more fresh vegetables in all or its specific items of cabbage, nori, and kelp. N-desmethyl-acetamiprid was more likely to be detected in children who drank more tap water. The maximum HQ and HI were 0.3522 and 0.5187, respectively, and 2.8% of children had a HI between 0.1 and 1. CONCLUSION: Predictors for the exposure of children to neonicotinoids included demographic and socioeconomic factors, physical exercise, and relative body weight. Tap water and fresh vegetables were potential sources. A low risk was posed on children's health by the neonicotinoids.

Prevalence and associated factors of Treponema pallidum infection in a rural area of southwestern China.

BACKGROUND: Epidemiological data on Treponema pallidum infection are scarce from the southwestern region of China. The purpose of this study was to determine the distribution and determinants of T. pallidum infection in the region. METHODS: A community-based cross-sectional study of 2608 participants aged ≥14 years was conducted in a rural area of southwestern China in 2014-15. A pretested questionnaire was used to collect sociodemographic characteristics and other factors associated with T. pallidum infection. The diagnoses of T. pallidum, human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV) infections were determined by commercial test kits. Logistic regression analysis was used to determine the correlates for T. pallidum infection, and adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated. RESULTS: The prevalence of T. pallidum infection was 1.2% (95% CI 0.8 to 1.7%). Risk factors varied by gender. In the male group, T. pallidum infection was significantly associated with ever injection drug use (aOR = 9.42, 95% CI 2.47 to 35.87) and HCV infection (aOR = 13.28, 95% CI 3.20 to 51.70). In the female group, correlates for T. pallidum infection included spouse having syphilis (aOR = 126.66, 95% CI 7.58 to 2122.94), ever having blood transfusion (aOR = 10.51, 95% CI 1.58 to 41.21) and HBV infection (aOR = 4.19, 95% CI 1.35 to 10.93). CONCLUSIONS: The prevalence of T. pallidum infection was high in the rural area of southwestern China. Correlates for T. pallidum infection varied with sex specific. Intervention should be developed for the prevention and control of T. pallidum infection.

Profit considerations in vaccine safety-related events in China.

Objectives: China has made remarkable achievements in the field of immunization. However, several widespread vaccine safety-related events have recently received worldwide attention and reflect flaws in vaccine management. This study aimed to summarize vaccine safety-related events between 1985 and 2018 in China and analyze the profit motives of these events.Methods. Literature and media reviews were conducted to discover vaccine safety-related events. We developed a conceptual model with profit-related variables, and using information available from each event, we identified which profit-related variable was implicated, and how it related to the pursuit of higher profits.Results: A total of 39 vaccine safety-related events were found in vaccine production, procurement, transportation, and daily management, along with adverse events following immunization (AEFIs). Overall, 90% (35/39) of the events could be classified as profit-driven. The motives of most events could be tied to one or more reasons, including decreasing costs among vaccine producers (67%, 26/39), reducing actual procurement price (67%, 26/39), and reducing costs of transportation and/or cold chain (24/39, 62%).Conclusions: In order to deal with vaccine-related challenges, a more restrictive supervision system on vaccine production and more emergency preparedness, including health and risk communication strategies, for vaccine safety should be implemented.

Factors associated with exposure of pregnant women to perfluoroalkyl acids in North China and health risk assessment.

Perfluoroalkyl acids (PFAAs) have been frequently found in blood of pregnant women, but the predictors and potential health risk have not been well studied in China. We recruited 534 pregnant women in Tangshan City of Hebei Province in North China between 2013 and 2014 and measured five PFAAs in serum during their early term of pregnancy, including perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid (PFHxS), perfluoro­n­undecanoic acid (PFUdA), and perfluorononanoic acid (PFNA). We explored the factors associated with the levels of serum PFAAs and assessed associated health risks. Food consumption information was obtained by food frequency questionnaire covering 100 items. Multiple linear regression model was used to determine the associations of sociodemographic, anthropometric, and food factors with the concentrations of serum PFAAs. Some PFAAs in serum were positively associated with age and body mass index (BMI). Consumption of beans, aquatic products, and eggs was positively associated with the concentrations of several PFAAs after adjusting for important covariates. Pregnant women who ate more cereal, vegetables, mushrooms and alga tended to have lower levels of serum PFOA, PFOS and PFNA. The Hazard index (HI) for reproductive toxicity and developmental toxicity was below 0.8, and the HI for hepatotoxicity beyond 1 was found in 0.37% of pregnant women. These results suggested that age, BMI, and some food consumption were predictors for the exposure to PFAAs in Chinese pregnant women. More attention should be paid to the hepatotoxicity for these exposures.

Exposure of Adults to Antibiotics in a Shanghai Suburban Area and Health Risk Assessment: A Biomonitoring-Based Study.

An extensive exposure to antibiotics has been demonstrated in children and pregnant women by biomonitoring, but data from general adults remain limited. In the current study, we studied 822 adults aged 21-75 years in Shanghai in 2017 and analyzed 18 common antibiotics (five veterinary antibiotics (VAs), four human antibiotics (HAs), and nine human/veterinary antibiotics (H/VAs)) in spot urine by liquid chromatography coupled to high-resolution mass spectrometry. All 18 antibiotics were detected in urine with an overall detection frequency of 45.9% and the detection frequency for each ranged from 0.1% to 15.2%. HAs, VAs, H/VAs, and VAs+H/VAs were detected in 4.4%, 11.6%, 38.0, and 44.5% of urine samples, respectively. Adults with the sum of estimated daily exposure dose of all the antibiotics below 1.55 µg/kg/day accounted for 89.1% of adults tested positive. A hazard index value beyond one was seen in 7.2% of adults based on microbiological effect. Ciprofloxacin was the biggest contributor to HI and its hazard quotient value more than one was seen in 5.6% of adults. These findings indicated an extensive exposure to low-dose multiple antibiotics in adults in Shanghai and some adults were at health risk related to the disturbance of gut microbiota.

Predictors of urinary antibiotics in children of Shanghai and health risk assessment.

BACKGROUND: An extensive exposure to antibiotics has been confirmed in children, but the predictors and potential health risk remain unclear. OBJECTIVE: To investigate the predictors of antibiotics in urine and potential health risk in children of Shanghai. METHODS: We selected 284 school children aged 8-11 years from a central area of Shanghai, China, in 2017. Ultra-performance liquid chromatography coupled with high-resolution mass spectrometry was used to measure 20 antibiotics, including four human antibiotics (HAs), six veterinary antibiotics (VAs), 10 human/veterinary antibiotics (H/VAs), and three metabolites in first morning urine. Logistic regression model was used to examine the associations of 17 variables related to demographic and socioeconomic factors, recent antibiotic use, drinking water intake, food consumption, and anthropometric measurements with the detection frequency of HAs, VAs, or H/VAs in urine. After daily intake was estimated, health risk was assessed for VAs and H/VAs by using hazard quotient (HQ) and hazard index (HI) based on microbiological or toxicological effects. RESULTS: The detection frequencies of 20 antibiotics and three metabolites ranged from 0 to 27.8% with an overall detection frequency being 56.0%. The detection frequency of HAs increased with age and screen time at weekend. Sex, age, family income and screen time were positively associated with the detection frequencies of VAs and H/VAs. Children reporting antibiotic use in the past three months had a higher detection frequency of HAs. Children with a higher consumption frequency of dairy products had a higher detection frequency of VAs + H/VAs, but a lower detection frequency of HAs. An increased overall detection frequency of all antibiotics was seen in children with higher consumption frequencies of aquatic products, livestock and poultry meat, or milk and dairy products. HQ >1 was only found for ciprofloxacin (5.6%) and ofloxacin (0.4%) based on microbiological effect. HI >1 was found in 6.0% of children for microbiological effect and none was found for toxicological effect. CONCLUSIONS: Predictors for antibiotics in urine for children included sex, age, family income, screen time, clinical use, and animal-derived food consumption. There was potential health risk for children with exposure to antibiotics.

Price adjustment for traditional Chinese medicine procedures: Based on a standardized value parity model.

Traditional Chinese medicine (TCM) is an important part of China's medical system. Due to the prolonged low price of TCM procedures and the lack of an effective mechanism for dynamic price adjustment, the development of TCM has markedly lagged behind Western medicine. The World Health Organization (WHO) has emphasized the need to enhance the development of alternative and traditional medicine when creating national health care systems. The establishment of scientific and appropriate mechanisms to adjust the price of medical procedures in TCM is crucial to promoting the development of TCM. This study has examined incorporating value indicators and data on basic manpower expended, time spent, technical difficulty, and the degree of risk in the latest standards for the price of medical procedures in China, and this study also offers a price adjustment model with the relative price ratio as a key index. This study examined 144 TCM procedures and found that prices of TCM procedures were mainly based on the value of medical care provided; on average, medical care provided accounted for 89% of the price. Current price levels were generally low and the current price accounted for 56% of the standardized value of a procedure, on average. Current price levels accounted for a markedly lower standardized value of acupuncture, moxibustion, special treatment with TCM, and comprehensive TCM procedures. This study selected a total of 79 procedures and adjusted them by priority. The relationship between the price of TCM procedures and the suggested price was significantly optimized (p < 0.01). This study suggests that adjustment of the price of medical procedures based on a standardized value parity model is a scientific and suitable method of price adjustment that can serve as a reference for other provinces and municipalities in China and other countries and regions that mainly have fee-for-service (FFS) medical care.

Urinary Antibiotics of Pregnant Women in Eastern China and Cumulative Health Risk Assessment.

Exposure to antibiotics during pregnancy can pose a systematic effect on human health. A few biomonitoring studies have demonstrated an extensive exposure of children to antibiotics, but there is still a lack of data for pregnant women. To assess the exposure of pregnant women to antibiotics and potential health risk, we investigated 536 pregnant women aged 16-42 years from two geographically different study sites in Eastern China in 2015. We measured 21 antibiotics of five categories (seven fluoroquinolones, three phenicols, four tetracyclines, three macrolides, and four sulfonamides) in urine using the isotope dilution ultraperformance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry. The hazard index (HI) was calculated on the basis of estimated daily exposure dose and acceptable daily intakes. A total of 16 antibiotics were found in urine, with detection frequencies between 0.2 and 16.0%. Antibiotics were overall detected in 41.6% of urine, and two or more antibiotics were detected in 13.1% of urine. Ciprofloxacin, ofloxacin, and trimethoprim were most frequently detected in urine, with detection frequencies between 10 and 20%. The majority of the antibiotics tested had an estimated daily exposure dose less than 1 µg/kg/day, and 4.3% of pregnant women had a HI value of more than 1. These findings indicated that pregnant women were frequently exposed to antibiotics and some individuals were in the potential risk of adverse microbiological effects induced by antibiotics.

[Detection and assessment of antibiotic and sex hormone residues in Eriocheir sinensis sold in markets in Shanghai].

OBJECTIVE: To understand the antibiotic and sex hormone residue level in the Eriocheir sinensis sold in markets in Shanghai. METHODS: Fifty six mitten crabs were collected through convenient sampling in Xuhui and Changning districts in Shanghai in 2014. The residues of 13 antibiotics (4 quinolones, 3 sulfonamides, 2 tetracyclines, 2 amphenicols, 1 macrolides, and trimethoprim) and 7 sex hormones (4 endogenous sex hormones and 3 synthetic sex hormones) were detected by the isotope dilution method based on ultra-performance liquid chromatography coupled to quadrupole/time-of-flight mass spectrometry in visceral organs and muscles of crabs. RESULTS: A total of 7 antibiotics were detected in visceral organs or muscles of crabs, including 3 quinolones (ciprofloxacin, norfloxacin, and enrofloxacin), 3 sulfonamides (sulfamethazine, sulfadiazine, and sulfamethoxazole) and trimethoprim. In visceral organs, the overall antibiotic detection rate was 32.1%, the maximum sum of mass concentration was 23.8 µg/kg, and the 75th percentile was 1.45 µg/kg. In muscles, the overall antibiotic detection rate was 39.3%, the maximum sum of mass concentration was 40.5 µg/kg, and the 75th percentile was 1.75 µg/kg. No sex hormones were detected in both visceral organs and muscles. CONCLUSION: The antibiotic and sex hormone residue level in the Eriocheir sinensis sold in markets in Shanghai did not exceed the national standard, indicating that no risk was posed to human health.

[An assessment of association of thyroid volume with growth indicators and comparison of different thyroid volume indexes in school-aged children].

OBJECTIVE: To analyze the association between thyroid volume and physical growth of school-age children, and to compare volume indexes of individual thyroids for reference of selection of assessment indicators. METHODS: All the students of the 12 classes of grades 3-5 at a primary school in Minhang district, Shanghai were rounded up with a multi-stage cluster sampling, for physical examinations to measure their height, weight, Body mass index (BMI) and body surface area (BSA), followed by B-ultrasonography to measure their thyroid volume. Data of the measurements were calculated to learn their height corrected volume index (HVI), weight and height corrected volume index (WHVI), BMI corrected volume (BMIV), and BSA corrected volume (BSAV) individually. Their urine and salt samples were collected to measure iodine concentration in urine and salt. Individual indexes were studied for their association with the growth and development indexes of children. RESULTS: Thyroid volume data were collected for 485 students, including 258 boys (53.2%) and 227 girls (46.8%). Their height, weight, BMI and BSA were found to be positively correlated with their age (P < 0.05). For children of the same age group, their thyroid volume was also positively correlated with their physical development indexes. Of all the thyroid indexes, the difference between BSAV physical development factors had no statistical association (with partial-correlation coefficients for age, gender, height, and weight being 0.07, 0.05, 0.01 and 0.02 respectively), and their thyroid volume, HVI, BMI and weight were correlated to age, height and weight. CONCLUSION: Thyroid volume was associated with age and weight. It was inappropriate to diagnose goiter with criteria of age, gender and thyroid volume. BSAV was recommended for its non-association with age, gender and weight and its stability.

Urinary excretion of phthalate metabolites in school children of China: implication for cumulative risk assessment of phthalate exposure.

We analyzed 13 metabolites of 9 phthalates in urine of 782 Chinese school children aged 8­11 years and estimated the daily intake for phthalates based on urinary metabolite levels. The daily intakes were compared with acceptable intake levels to calculate the hazard quotient (HQ) for single phthalate. Finally, the cumulative risk for each child was assessed by means of a hazard index (HI) which is the sum of HQs. Overall, 11 metabolites were found in at least 85% of the urine samples with the highest median concentration of 47.1 ng/mL (93.4 µg/g creatinine) for mono-n-butyl phthalate (MnBP). Monooctyl phthalate (MOP) and monoisononyl phthalate (MiNP) were not detectable. The cumulative risk assessment covering di(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DnBP), di-isobutyl phthalate (DiBP), and butyl-benzyl phthalate (BBzP) demonstrated that 19.8% (volume model-based) and 40.3% (creatinine model-based) of the children exceeded 1 for the HI based on tolerable daily intake (TDI) values (considered as potential adverse antiandrogenic effect). Furthermore, at least 36% of the children from the manufacturing-intensive region had a HI higher than 1. The results indicate that Chinese children are widely exposed to phthalates and those from manufacturing-intensive regions are probably at a high risk of cumulative phthalate exposure.

Rapid and sensitive screening and selective quantification of antibiotics in human urine by two-dimensional ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry.

A rapid and sensitive method for the screening and selective quantification of antibiotics in urine by two-dimensional ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was developed. This method allowed the injection of 200 µL urine extract. The 200-µL injection volume used in this method increased the absolute sensitivity for target antibiotics in solvent by an average 13.3 times, with a range from 8.4 to 28.5 times, compared with the 10-µL conventional injection volume. A 96-well solid phase extraction procedure was established to eliminate the contamination on the chromatographic column resulting from the large-volume injection and increase the throughput of sample preparation. Fourteen target antibiotics from six common categories (ß-lactams, quinolones, tetracyclines, macrolides, sulfonamides, and chloramphenicols) were selected as model compounds, and a database containing an additional 74 antibiotics was compiled for posttarget screening. The limit of detection of the target antibiotics, defined as a signal-to-noise ratio of 3, ranged from 0.04 to 1.99 ng/mL. The mean interday recoveries ranged between 79.6 and 121.3 %, with a relative standard deviation from 2.9 to 18.3 % at three spiking levels of 20 ng/mL, 50 ng/mL, and 100 ng/mL. This method was successfully applied in 60 real urine samples from schoolchildren aged 8-11 years, and four target antibiotics (azithromycin, sulfadiazine, trimethoprim, and oxytetracycline) and two posttarget antibiotics (sulfadimidine and cefaclor) were found in the urine samples. This method can be used as a large-scale biomonitoring tool for exposure of the human population to antibiotics.

Rapid and sensitive analysis of phthalate metabolites, bisphenol A, and endogenous steroid hormones in human urine by mixed-mode solid-phase extraction, dansylation, and ultra-performance liquid chromatography coupled with triple quadrupole mass spectrometry.

Steroid hormone levels in human urine are convenient and sensitive indicators for the impact of phthalates and/or bisphenol A (BPA) exposure on the human steroid hormone endocrine system. In this study, a rapid and sensitive method for determination of 14 phthalate metabolites, BPA, and ten endogenous steroid hormones in urine was developed and validated on the basis of ultra-performance liquid chromatography coupled with electrospray ionization triple quadrupole mass spectrometry. The optimized mixed-mode solid phase-extraction separated the weakly acidic or neutral BPA and steroid hormones from acidic phthalate metabolites in urine: the former were determined in positive ion mode with a methanol/water mobile phase containing 10 mM ammonium formate; the latter were determined in negative ion mode with a acetonitrile/water mobile phase containing 0.1 % acetic acid, which significantly alleviated matrix effects for the analysis of BPA and steroid hormones. Dansylation of estrogens and BPA realized simultaneous and sensitive analysis of the endogenous steroid hormones and BPA in a single chromatographic run. The limits of detection were less than 0.84 ng/mL for phthalate metabolites and less than 0.22 ng/mL for endogenous steroid hormones and BPA. This proposed method had satisfactory precision and accuracy, and was successfully applied to the analyses of human urine samples. This method could be valuable when investigating the associations among endocrine-disrupting chemicals, endogenous steroid hormones, and relevant adverse outcomes in epidemiological studies.

Long-term impact of the World Bank Loan Project for schistosomiasis control: a comparison of the spatial distribution of schistosomiasis risk in China.

BACKGROUND: The World Bank Loan Project (WBLP) for controlling schistosomiasis in China was implemented during 1992-2001. Its short-term impact has been assessed from non-spatial perspective, but its long-term impact remains unclear and a spatial evaluation has not previously been conducted. Here we compared the spatial distribution of schistosomiasis risk using national datasets in the lake and marshland regions from 1999-2001 and 2007-2008 to evaluate the long-term impact of WBLP strategy on China's schistosomiasis burden. METHODOLOGY/PRINCIPAL FINDINGS: A hierarchical Poisson regression model was developed in a Bayesian framework with spatially correlated and uncorrelated heterogeneities at the county-level, modeled using a conditional autoregressive prior structure and a spatially unstructured Gaussian distribution, respectively. There were two important findings from this study. The WBLP strategy was found to have a good short-term impact on schistosomiasis control, but its long-term impact was not ideal. It has successfully reduced the morbidity of schistosomiasis to a low level, but can not contribute further to China's schistosomiasis control because of the current low endemic level. A second finding is that the WBLP strategy could not effectively compress the spatial distribution of schistosomiasis risk. To achieve further reductions in schistosomiasis-affected areas, and for sustainable control, focusing on the intermediate host snail should become the next step to interrupt schistosomiasis transmission within the two most affected regions surrounding the Dongting and Poyang Lakes. Furthermore, in the lower reaches of the Yangtze River, the WBLP's morbidity control strategy may need to continue for some time until snails in the upriver provinces have been well controlled. CONCLUSION: It is difficult to further reduce morbidity due to schistosomiasis using a chemotherapy-based control strategy in the lake and marshland regions of China because of the current low endemic levels of infection. The future control strategy for schistosomiasis should instead focus on a snail-based integrated control strategy to maintain the program achievements and sustainably reduce the burden of schistosomiasis in China.

Urbanisation and health in China.

China has seen the largest human migration in history, and the country's rapid urbanisation has important consequences for public health. A provincial analysis of its urbanisation trends shows shifting and accelerating rural-to-urban migration across the country and accompanying rapid increases in city size and population. The growing disease burden in urban areas attributable to nutrition and lifestyle choices is a major public health challenge, as are troubling disparities in health-care access, vaccination coverage, and accidents and injuries in China's rural-to-urban migrant population. Urban environmental quality, including air and water pollution, contributes to disease both in urban and in rural areas, and traffic-related accidents pose a major public health threat as the country becomes increasingly motorised. To address the health challenges and maximise the benefits that accompany this rapid urbanisation, innovative health policies focused on the needs of migrants and research that could close knowledge gaps on urban population exposures are needed.

High prevalence of hyperglycaemia and the impact of high household income in transforming rural China.

BACKGROUND: The prevalence of hyperglycaemia and its association with socioeconomic factors have been well studied in developed countries, however, little is known about them in transforming rural China. METHODS: A cross-sectional study was carried out in 4 rural communities of Deqing County located in East China in 2006-07, including 4,506 subjects aged 18 to 64 years. Fasting plasma glucose (FPG) was measured. Subjects were considered to have impaired fasting glucose (IFG) if FPG was in the range from 5.6 to 6.9 mmol/L and to have diabetes mellitus (DM) if FG was 7.0 mmol/L or above. RESULTS: The crude prevalences of IFG and DM were 5.4% and 2.2%, respectively. The average ratio of IFG/DM was 2.5, and tended to be higher for those under the age of 35 years than older subjects. After adjustment for covariates including age (continuous), sex, BMI (continuous), smoking, alcohol drinking, and regular leisure physical activity, subjects in the high household income group had a significantly higher risk of IFG compared with the medium household income group (OR: 1.74, 95% CI: 1.11-2.72) and no significant difference in IFG was observed between the low and medium household income groups. Education and farmer occupation were not significantly associated with IFG. CONCLUSIONS: High household income was significantly associated with an increased risk of IFG. A high ratio of IFG/DM suggests a high risk of diabetes in foreseeable future in the Chinese transforming rural communities.

Nonparametric evaluation of dynamic disease risk: a spatio-temporal kernel approach.

Quantifying the distributions of disease risk in space and time jointly is a key element for understanding spatio-temporal phenomena while also having the potential to enhance our understanding of epidemiologic trajectories. However, most studies to date have neglected time dimension and focus instead on the "average" spatial pattern of disease risk, thereby masking time trajectories of disease risk. In this study we propose a new idea titled "spatio-temporal kernel density estimation (stKDE)" that employs hybrid kernel (i.e., weight) functions to evaluate the spatio-temporal disease risks. This approach not only can make full use of sample data but also "borrows" information in a particular manner from neighboring points both in space and time via appropriate choice of kernel functions. Monte Carlo simulations show that the proposed method performs substantially better than the traditional (i.e., frequency-based) kernel density estimation (trKDE) which has been used in applied settings while two illustrative examples demonstrate that the proposed approach can yield superior results compared to the popular trKDE approach. In addition, there exist various possibilities for improving and extending this method.