Effects of cigarette smoking associated with sarcopenia in persons 60 years and older: a cross-sectional study in Zhejiang province.

PURPOSE: Smoking is a risk factor for sarcopenia. Nevertheless, few studies analyzed the independent effects of various smoking dimensions (duration, intensity, cumulative dose) on sarcopenia risk. This is a cross-sectional study based on an older population in Zhejiang Province to determine which smoking dimensions are mainly important for sarcopenia risk and to explore the dose-response relationship between them. METHODS: Our study included 783 patients with sarcopenia and 4918 non-sarcopenic individuals. Logistic regression and restricted cubic with logistic regression (for nonlinear dose effects) were used to obtain odds ratios (ORs) and 95% confidence intervals as well as restricted cubic splines (RCS) curves. RESULTS: Compared with never-smokers, current smokers had an increased risk of sarcopenia (OR = 1.786; 95% CI 1.387-2.301) after adjusting for confounders such as age, sex, education, alcohol consumption, disease history, etc. There was no significant association between smoking intensity and sarcopenia after more than 20 cigarettes per day (OR = 1.484; 95% CI 0.886-2.487), whereas the risk of sarcopenia increased significantly with increasing duration of smoking after more than 40 years (OR = 1.733; 95% CI 1.214-2.473). Meanwhile, there was a significant non-linear dose-response relationship between smoking duration or intensity and the risk of sarcopenia. However, the risk of sarcopenia increased linearly with the number of pack-years of smoking, which is not a significant nonlinear dose-response relationship. CONCLUSIONS: This study indicated the association between smoking and sarcopenia. Both smoking duration and cumulative dose were significantly and positively associated with sarcopenia. These findings reflect the important role of the number of years of smoking in increasing the risk of sarcopenia and provide scientific evidence that different smoking dimensions may influence the risk of the sarcopenia.

Association between ambient fine particular matter components and subsequent cognitive impairment in community-dwelling older people: a prospective cohort study from eastern China.

BACKGROUND: Fine particular matter (PM2.5) has been associated with dementia, but limited information is available regarding the association between PM2.5 components and dementia. AIMS: We aimed to identify the major components of PM2.5 that affect cognitive function to further investigate its mechanism of action, and develop a prevention strategy for dementia. METHODS: In this study, we included 7804 participants aged ≥ 60 years recruited from seven counties in Zhejiang province, eastern China. The participants completed the baseline survey between 2014 and 2015, and were followed up until the end of 2020. We adopted single-component robust Poisson regression models for analyses, and estimated relative risks and 95% confidence intervals describing associations between the chemical constituents of PM2.5 exposure and incident cognitive impairment in those who were free from cognitive impairment at baseline. RESULTS: Significantly positive associations were observed between sulfate, nitrate, ammonium, and organic matter in PM2.5 and incident cognitive impairment across different exposure periods; the relative risks of 10-year exposure before enrollment ranged from 1.01 to 1.02. However, we did not find a significant association between black carbon and cognitive impairment. The point estimates of the relative risk values did not change substantially after performing the sensitivity analyses. CONCLUSIONS: Our findings strengthen the idea that long-term exposure to PM2.5 mass and its chemical components is associated with an elevated risk of incident cognitive impairment among older adults.

Egg consumption reduces the risk of depressive symptoms in the elderly: findings from a 6-year cohort study.

BACKGROUND: Accumulating evidence showed that dietary habits might modify the risk of depression. This study aimed to evaluate the longitudinal association of egg consumption with depressive symptoms in the Chinese elderly. METHODS: We analyzed the data from Zhejiang Ageing and Health Cohort Study including 8289 participants. The Patient Health Questionnaire-9 scale (PHQ-9) was used to assess depressive symptoms at baseline and three waves of follow-up (2015, 2016, and 2019-2020). A PHQ-9 cut-off score ≥ 5 was used to define depressive symptoms. The participants with depressive symptoms at baseline were excluded. Egg consumption was evaluated through the diet habits section of the baseline questionnaire. Self-reported egg consumption was measured as the number of eggs per week and categorized into three categories. Log-binomial regression models with Generalized Estimating Equations were utilized to evaluate the association of egg consumption with depressive symptoms and estimate relative risks (RRs). RESULTS: The mean age of included participants was 68.6 years. After 6 years of follow-up, 1385 (16.7%) participants were indicated with depressive symptoms by PHQ-9 at least once. Compared with non-consumers or less-than-weekly consumers, participants consuming < 3 eggs/week and ≥ 3 eggs/week had 30% (RR = 0.70, 95%CI 0.62-0.80) and 38% (RR = 0.62, 95%CI 0.54-0.71) lower risks of depressive symptoms, respectively. A linear association was confirmed (P for trend < 0.01), and each egg increment per week was associated with a 4% lower risk of depressive symptoms (RR = 0.96, 95%CI 0.93-0.99). Sensitivity analyses yielded consistent results to the main analyses. CONCLUSIONS: Egg consumption is prospectively related to a lower risk of depressive symptoms in the Chinese elderly. More prospective studies are needed to verify the association.

A machine learning-based data mining in medical examination data: a biological features-based biological age prediction model.

BACKGROUND: Biological age (BA) has been recognized as a more accurate indicator of aging than chronological age (CA). However, the current limitations include: insufficient attention to the incompleteness of medical data for constructing BA; Lack of machine learning-based BA (ML-BA) on the Chinese population; Neglect of the influence of model overfitting degree on the stability of the association results. METHODS AND RESULTS: Based on the medical examination data of the Chinese population (45-90 years), we first evaluated the most suitable missing interpolation method, then constructed 14 ML-BAs based on biomarkers, and finally explored the associations between ML-BAs and health statuses (healthy risk indicators and disease). We found that round-robin linear regression interpolation performed best, while AutoEncoder showed the highest interpolation stability. We further illustrated the potential overfitting problem in ML-BAs, which affected the stability of ML-Bas' associations with health statuses. We then proposed a composite ML-BA based on the Stacking method with a simple meta-model (STK-BA), which overcame the overfitting problem, and associated more strongly with CA (r = 0.66, P < 0.001), healthy risk indicators, disease counts, and six types of disease. CONCLUSION: We provided an improved aging measurement method for middle-aged and elderly groups in China, which can more stably capture aging characteristics other than CA, supporting the emerging application potential of machine learning in aging research.

Impact of air pollution exposure on the risk of Alzheimer's disease in China: A community-based cohort study.

Alzheimer's disease (AD) is the most common type of dementia. Impact of air pollution (AP) on the risk of AD is unclear. It is unknown which air pollutants are independently associated with AD and whether fish consumption mitigated the association. We carried out a community-based cohort of 6115 participants aged ≥60 years in China to examine the association of PM2.5, PM10, CO, NO2, SO2 and O3 exposure with AD, and differences in the association between people with low and high consumption of fish. The participants were randomly recruited from six counties in Zhejiang province for health survey to document socio-demographic and disease risk factors in 2014, and were followed up to diagnose AD in 2019. A total of 986 cohort members were diagnosed with AD. Based on the daily mean air pollutants monitored in 2013-2015 in the counties, participants were divided into low, middle and high AP exposure groups for subsequent analysis. The multiple adjusted odds ratio (OR) of AD in participants living with the middle and high levels of PM2.5 exposure versus the low exposure were 1.50 (95% CI 0.90-2.50) and 3.92 (2.09-7.37). The increased ORs were also with PM10 (1.74, 0.65-4.64; 3.00, 1.22-7.41) and CO (2.86, 1.32-6.20; 1.19, 0.45-3.18), but not with NO2 (0.63, 0.17-2.27; 0.95, 0.28-3.19), SO2 (0.44, 0.19-1.001; 1.21, 0.56-2.62), and O3 (0.38, 0.20-0.74; 0.50, 0.21-1.21). There were no significant interaction effects of AP with fish consumption on AD. However, participants with low consumption of fish appeared to have higher ORs in PM2.5 exposure (1.80, 1.39-2.33; 5.18, 3.93-6.82) than those high consumption (1.38, 0.78-2.47; 2.89, 1.50-5.59). Our findings of PM2.5, PM10 and CO exposure significantly increased the risk of AD and the potential mitigating effect of fish consumption on the association provide evidence for developing effective strategies for AD reduction and air pollution control.

Risk of severe coronavirus disease in imported and secondary cases in Zhejiang province, China.

BACKGROUND: To our knowledge, no previous studies have focused on determining whether the virulence and case fatality rate of the severe acute respiratory coronavirus 2 (SARS-CoV-2) decreases as the virus continues to spread. Hence, our aim was to retrospectively explore the differences in the risk of severe or critical COVID-19 among imported, secondary and tertiary cases in Zhejiang, China. METHODS: We categorized COVID-19 cases reported by hospitals in Zhejiang as first-, second- and third-generation cases. Univariate and multivariate logistic regression analyses were performed to compare disease severity and case generation. RESULTS: Of 1187 COVID-19 cases, 227 (19.1%, 95% CI: 16.9-21.4) manifested severe or critical illness. The adjusted risk difference for severe or critical illness was lower for second- (odds ratio (OR) = 0.84, 95% confidence interval (CI): 0.52-1.36) and third-generation (OR = 0.55, 95% CI: 0.37-0.83) cases than for first-generation cases. Compared with hospitalized patients, cases identified at centralized isolation locations (OR = 0.62, 95% CI: 0.40-0.97) and those identified through active search or gateway screening (OR = 0.28, 95% CI: 0.08-1.04) were at a lower risk of severe or critical illness. CONCLUSIONS: Second- and third-generation cases of COVID-19 have a lower risk of developing severe or critical illness than first-generation cases.

Blood pressure and cognitive decline over the course of 2 years in elderly people: a community-based prospective cohort study.

BACKGROUND: Numerous studies have shown a significant association between blood pressure (BP) and cognition, but little is known about the effect of BP on the rate of cognitive decline. AIMS: To investigate the relationship between blood pressure and the subsequent rate of cognitive decline in elderly people. METHODS: Based on a prospective cohort that has been followed since 2014, we collected baseline blood pressures and other covariates in 7874 Chinese individuals aged 60 years or older, and followed their cognitive change using the Mini-Mental State Examination (MMSE) until Dec 31, 2016. Linear mixed-effects models were used to measure changes in MMSE scores over time in relation to blood pressure values, and in addition to the covariates, we included random effects for intercepts and slopes. RESULTS: In the non-hypertension group, we observed that faster cognitive decline was associated with higher systolic blood pressure, lower diastolic blood pressure, lower mean arterial pressure, and higher pulse pressure. In the hypertension group, lower diastolic blood pressure, lower mean arterial pressure, and higher pulse pressure were associated with faster cognitive decline, but not systolic blood pressure. CONCLUSION: Higher systolic blood pressure, lower diastolic blood pressure, lower mean arterial pressure, and higher pulse pressure accelerate the subsequent rate of cognitive decline in elderly people. The results of this study may help improve blood-pressure control strategies to prevent cognitive decline.

Impact of heatwaves on daily outpatient visits of respiratory disease: A time-stratified case-crossover study.

OBJECTIVES: This study aims to estimate the impact of heatwaves from July 2010 to October 2012 on daily outpatient visits for respiratory disease (RD) in Cangnan, China and identify vulnerable populations. METHODS: The definition of heatwave was a period at least 3 consecutive days with maximum temperature exceeding 35 °C in this study. A time-stratified case-crossover design was conducted to examine the relationship between heatwaves and outpatient visits for RD. Patient data for the period from 2010 to 2012 were collected from the Third People's Hospital of Cangnan and daily meteorological data for the same period were collected from the China Meteorological Data Service Center. Data regarding the air pollution index (API), a composite indicator of air pollution, were collected from the Data Center of the Chinese Ministry of Environmental Protection. RD were identified based on the 10th revision International Classification of Diseases (ICD-10) codes (J00-J99). A conditional Poisson regression model was applied to examine the heatwave-RD association using the Relative Risk (RR) while adjusting for meteorological and air pollution factors including temperature, rainfall, wind speed, pressure, humidity, sunshine hours and API. RESULTS: During the study period, 4 heatwaves occurred and a total of 1732 outpatient visits for RD were reported. Heatwaves increased the frequency of RD outpatient visits and the highest RR of total RD was 1.155% and 95% Confidence Intervals (95% CI) was 1.084-1.232 at Lag 0. For subcategories, heatwaves increased the risk of infectious RD (Lag 0: RR =1.182, 95% CI: 1.106-1.263) and decreased the risk of non-infectious RD ((Lag 6: RR =0.750, 95% CI: 0.568-0.990). Moreover, heatwaves showed adverse effects on acute upper respiratory infection (Lag 0: RR =1.306, 95% CI: 1.177-1.450). The RR of outpatient visits for RD was statistically significant in females (Lag 0: RR =1.161, 95% CI: 1.046-1.298), males (Lag 4: RR =1.161, 95% CI: 1.096-1.261), young people aged 4-17 years (Lag 0: RR =1.741, 95% CI: 1.524-1.990) and elders aged 65 years or older (Lag 5: RR =1.412, 95% CI: 1.111-1.794) during heatwaves. CONCLUSIONS: Heatwaves had a significant harmful impact on daily outpatient visits for RD in Cangnan, especially for vulnerable population identified. These results can be used not only to strengthen the health education and protection of these vulnerable populations, but also to assist relevant organizations with developing intervention programmes and improving disease prevention and community care.

[Risk assessment for emergency events of infectious disease in outlying areas of large-scale activities].

OBJECTIVE: To identify and assess the potential public health risks of emergency events of infectious disease in the surrounding areas of Hangzhou during the 11th G20 summit, and to assess their impacts on the G20 summit. METHODS: The surrounding cities of Hangzhou included Ningbo, Wenzhou, Jiaxing, Huzhou, Shaoxing, Jinhua, Quzhou, Zhoushan, Taizhou and Lishui. Background information on infectious diseases in Zhejiang province was collected, and the brainstorming and expert consultation methods were used to identify the risks. The local risks and the impact of local risks on the G20 summit were assessed. RESULTS: The criteria for public health risk was first established. Through the assessments,a total of 27 kinds of infectious diseases in 4 types of public health risks were identified. The impact of these risks on Hangzhou G20 summit was divided into 1 item of high-risk, 12 items of medium risk and 14 items of low risk.According to the results of risk assessment, the recommendations for risk management of respiratory infectious diseases, intestinal infectious diseases, imported infectious diseases like Middle East respiratory syndrome and other infectious diseases were made. With risk management, Middle East respiratory syndrome was not occurred during the G20 summit, and the epidemic situation of other infectious diseases with middle or low risks was almost the same with that of past years. CONCLUSIONS: sThe public health risks of Hangzhou G20 summit from sudden infectious diseases in outlying areas are mainly medium and low risks. The recommendations on risk management provide a basis for reducing the adverse consequences of public health risks in the event of an outbreak of infectious diseases, avoiding the impact of various risk factors in the outlying areas on G20 summit.

Infectious diarrheal disease caused by contaminated well water in Chinese schools: A systematic review and meta-analysis.

BACKGROUND: In China, waterborne outbreaks of infectious diarrheal disease mainly occur in schools, and contaminated well water is a common source of pathogens. The objective of this review was to present the attack rates, durations of outbreak, pathogens of infectious diarrheal disease, and sanitary conditions of wells in primary and secondary schools in China, and to analyze risk factors and susceptibility of school children. METHODS: Relevant articles and reports were identified by searching PubMed, Web of Science, China National Knowledge Infrastructure, China Information System for Disease Control and Prevention, and the Chinese Field Epidemiology Training Program. Essential information, including urban/rural areas, school types, attack rates, pathogens, durations of outbreak, report intervals, and interventions were extracted from the eligible articles. Wilcoxon signed-rank test, Kruskal-Wallis H test, and Spearman correlation test were conducted in statistical analyses. Sex- and age-specific attack rate ratios were calculated as pooled effect sizes. RESULTS: We screened 2188 articles and retrieved data of 85 outbreaks from 1987 to 2014. Attack rates of outbreaks in rural areas (median, 12.63 cases/100 persons) and in primary schools (median, 14.54 cases/100 persons) were higher than those in urban areas (median, 5.62 cases/100 persons) and in secondary schools (median, 8.74 cases/100 persons) (P = 0.004 and P = 0.013, respectively). Shigella, pathogenic Escherichia coli, and norovirus were the most common pathogens. Boys tended toward higher attack rates than girls (sex-specific attack rate ratio, 1.13; 95% CI, 1.00-1.29, P = 0.05). Unsanitary conditions of water wells were reported frequently, and unhealthy behavior habits were common in students. CONCLUSION: School children were susceptible to waterborne disease in China. Chinese government should make efforts to improve access to safe water in schools. Health education promotion and conscientiousness of school leaders and teachers should be enhanced.

Tea and Risk of Age-Related Cataracts: A Cross-Sectional Study in Zhejiang Province, China.

BACKGROUND: The antioxidant properties of tea extracts are considered to be effective in protecting against cataracts. However, there is still insufficient epidemiological knowledge about the protective effects of different types of tea on age-related cataracts. METHODS: The data was derived from the Zhejiang Major Public Health Surveillance (ZJMPHS) Program on health and related factors in the elderly. The relationships between consumption of different types of tea and risk of age-related cataracts were assessed after adjusting for related covariates. RESULTS: The prevalence of age-related cataracts in this study population was 4.4% (409/9343). After adjustment for potential confounders, tea drinking was associated with reduced risk of age-related cataracts (adjusted odds ratio [OR] 0.65; 95% confidence interval [CI], 0.47-0.91). Compared to nondrinkers, green tea drinkers had a significantly reduced risk of cataracts (adjusted OR 0.58; 95% CI, 0.40-0.85). Average tea consumption of 14-27 cups (adjusted OR 0.55; 95% CI, 0.33-0.93) and over 28 cups (adjusted OR 0.58; 95% CI, 0.34-0.99) per week had a protective effect against cataracts in comparison to no consumption. In addition, ingesting a moderate concentration of tea significantly decreased the risk of cataract compared to no consumption (adjusted OR 0.43; 95% CI, 0.27-0.71). CONCLUSIONS: Tea ingestion was associated with reduced risk of age-related cataracts. In light of these findings, we suggest that reasonable tea consumption (ie, favoring green tea and consuming an average of over 500 mL per day at moderate concentration) should offer protection against age-related cataracts.

Association between eating alone and depressive symptom in elders: a cross-sectional study.

BACKGROUND: Depression is one of the main health concerns in elders which could lead to many negative outcomes. Eating alone is an emerging issue in elders in China and would become more serious along with the fast course of industrialization and urbanization, as well as population aging. However, their relationship was seldom researched. METHODS: Using a two-stage cluster sampling strategy, an investigation was conducted in 2014 among 9,361 permanent residents aged 60 years and above in Zhejiang Province, China. Totally, 7,968 cognitively normal elders were included in our analysis. Multilevel logistic regression was used to explore the association between eating arrangement (number of companions in mealtime) and depressive symptom as well as the association between eating alone and depressive symptom in relation to living alone. RESULTS: In our sample, 17.1% of the elders ate alone and 8.7% had depressive symptom. We observed a distinct inverse association between eating arrangement (number of companions in mealtime) and geriatric depressive symptom (female: OR = 1.12, P = 0.027; aged 60-74 years: OR = 1.16, P = 0.002), after adjustment for demography, socioeconomic status, social relation, health behaviors, underlying conditions and living alone. We then introduced a combined variable of eating alone and living alone and examined its relationship with depressive symptom. We found that compared with elders who ate and lived with others, those who ate alone but lived with others had a significant increased odds of depressive symptom (female: OR = 1.62, P = 0.027; aged 60-74 years: OR = 1.59, P = 0.025). CONCLUSIONS: Our results suggested that a lack of companionship in mealtime might be independently associated with geriatric depressive symptom for females and those aged 60-74 years. What's more, eating alone might be a stronger factor associated with depressive symptom than living alone. We recommend interventions to be performed in encouraging elders especially females and those aged 60-74 years to eat with others. Longitudinal studies in different populations which focus on this topic are required to better understand this issue.

Systematic review of severe fever with thrombocytopenia syndrome: virology, epidemiology, and clinical characteristics.

Severe fever with thrombocytopenia syndrome (SFTS) was firstly discovered in China in 2010, followed by several reports from many other countries worldwide. SFTS virus (SFTSV) has been identified as the causative agent of the disease and has been recognized as a public health threat. This novel Bunyavirus belongs to the Phlebovirus genus in the family Bunyaviridae. This review also describes the different aspects of virology, pathogenesis, epidemiology, and clinical symptoms on the basis of the published article surveillance data and phylogenetic analyses of viral sequences of large, medium, and small segments retrieved from database using mega 5.05, simplot 3.5.1, network 4.611, and epi information system 3.5.3 software. SFTS presents with fever, thrombocytopenia, leukocytopenia, and considerable changes in several serum biomarkers. The disease has 10~15% mortality rate, commonly because of multiorgan dysfunction. SFTSV is mainly reported in the rural areas of Central and North-Eastern China, with seasonal occurrence from May to September, mainly targeting those of ≥50 years of age. A wide range of domesticated animals, including sheep, goats, cattle, pigs, dogs, and chickens have been proven seropositive for SFTSV. Ticks, especially Haemaphysalis longicornis, are suspected to be the potential vector, which have a broad animal host range in the world. More studies are needed to elucidate the vector-animal-human ecological cycle, the pathogenic mechanisms in high level animal models and vaccine development.

Human infection and environmental contamination with Avian Influenza A (H7N9) Virus in Zhejiang Province, China: risk trend across the three waves of infection.

BACKGROUND: The third wave of H7N9 cases in China emerged in the second half of 2014. This study was conducted to identify the risk trends of H7N9 virus in human infections and environment contamination. METHODS: A surveillance program for H7N9 virus has been conducted in all 90 counties in Zhejiang since March 2013. All H7N9 cases were reported by hospitals through the China Information System for Disease Control and Prevention. Sampling sites for environment specimens were randomly selected by a multi-stage sampling strategy. Poultry-related workers for serological surveillance were randomly selected from the sampling sites for environmental specimens in the first quarter of each year. rRT-PCR and viral isolation were performed to identify H7N9 virus. A hemagglutination inhibition assay was conducted to detect possible H7N9 infection among poultry-related workers. RESULTS: A total of 170 H7N9 cases were identified in Zhejiang from 20 March 2013 to 28 February 2015. The proportion of rural cases increased from 42.2% (19/45) to 67.7% (21/31) with progression of the three epidemics (P < 0.05). In 32% (161/503) of towns and 16.0% (238/1488) of surveyed premises, H7N9 virus was detected in the environment. The positive rate of environmental specimens was 6.1% (868/14207). In addition, 912 poultry-related workers were recruited and 3.7% (34) of them tested positive for H7N9 antibodies. Positive detection of H7N9 virus during environmental surveillance increased from the first to third wave (P < 0.05). Almost all positive rates of environmental surveillance were higher in urban than rural in the second wave (P < 0.05), however they were higher in rural area in the third wave (P < 0.05). CONCLUSIONS: Our study highlights that the severity of poultry-related environmental contamination by H7N9 virus is intensifying. We strongly recommend that the local government stop illegal trading immediately and close live poultry markets in the territory. Poultry operations in slaughtering plants must be supervised rigorously. Prior to the closure of live poultry markets, daily cleaning and disinfecting of areas potentially contaminated by H7N9 virus, centralized collection and disposal of trash, designating certain days as market rest days, banning overnight poultry storage and other measures should be strictly carried out in both urban and rural areas.

Detection of spotted fever group Rickettsiae in ticks from Zhejiang Province, China.

Tick species distribution and prevalence of spotted fever group Rickettsiae (SFGR) in ticks were investigated in Zhejiang Province, China in 2010 and 2011. PCR was used to detect SFGR and positive amplicons were sequenced, compared to published sequences and phylogenic analysis was performed using MEGA 4.0. A total of 292 adult ticks of ten species were captured and 7.5 % (22/292) of the ticks were PCR-positive for SFG Rickettsia. The PCR-positive rates were 5.5 % (6/110) for Haemaphysalis longicornis, 3.6 % (1/28) for Amblyomma testudinarium and 16 % (15/94) for Ixodes sinensis, respectively. Phylogenetic analyses of gltA genes detected in ticks indicated that there are two dominating groups of SFGR. Sequences of group one were closely related to Rickettsia monacensis, whereas sequences of group two were closest related to Rickettsia heilongjiangensis and Rickettsia japonica, which are human pathogens. Our findings underline the importance of these ticks in public health surveillance in Zhejiang Province, China.

[Construction of early warning model of influenza-like illness in Zhejiang Province based on support vector machine].

OBJECTIVE: To construct a forecasting model of influenza-like illness in Zhejiang Province. METHODS: The number of influenza-like cases and related pathogens among outpatients and emergency patients were obtained from 11 sentinel hospitals in Zhejiang Province during 2012 to 2013 (total 104 weeks), and corresponding meteorological factors were also collected. The epidemiological characteristics of influenza during the period were then analyzed. Linear correlation and rank correlation analyses were conducted to explore the association between influenza-like illness and related factors. Optimal parameters were selected by cross validation. Support vector machine was used to construct the forecasting model of influenza-like illness in Zhejiang Province and verified by the historical data. RESULTS: Correlation analysis indicated that 8 factors were associated with influenza-like illness occurred in one week. The results of cross validation showed that the optimal parameters were C=3, ε=0.009 and γ=0.4. The results of influenza-like illness forecasting model after verification revealed that support vector machine had the accuracy of 50.0% for prediction with the same level, while it reached 96.7% for prediction within the range of one level higher or lower. CONCLUSION: Support vector machine is suitable for early warning of influenza-like illness.

[Semi-quantitative risk assessment on local transmission of Dengue fever caused by introduced cases].

OBJECTIVE: To assess the risk of local transmission of Dengue caused by introduced cases with semi-quantitative method in 2015 in Zhejiang Province. METHODS: Risk indexes of local transmission of Dengue caused by introduced cases were reviewed. The weights of indexes were computed by analytic hierarchy process and further used to generate absolute risk values by multiplying indexes. Moreover, comprehensive indexes were computed to describe relative risk by combining analytic hierarchy process and TOPSIS methods. RESULTS: Four primary indexes and 19 secondary indexes were identified for risk assessment of local transmission of Dengue. The indexes with maximum and minimum weight were the number of immigration from countries with Dengue patients (weight value: 0.0678) and density of population (weight value: 0.0371) respectively. All CR values, statistics for measuring consistency of score matrix, were less than 0.1 (minimum: 0.000, maximum: 0.0922, average: 0.0251). The absolute risk of Zhejiang Province was within the range of 0.397-0.504 (the full score was 1.0). The risk orders of 11 municipalities sorted by relative comprehensive indexes and absolute risk values methods were similar. The three highest municipalities were Hangzhou, Wenzhou and Ningbo and the ranges of absolute risk value were 0.387-0.494, 0.404-0.511 and 0.392-0.499 respectively. CONCLUSION: The results provides scientific basis for preventing and controlling Dengue in Zhejiang Province. The indexes and weights may be used to assess risk of Dengue in future. In addition, the semi-quantitative method constructed in this study would be a significant reference for risk assessment of public health in emergencies.

Enterovirus infection in children attending two outpatient clinics in Zhejiang Province, China.

Enteroviruses are responsible for hand, foot, and mouth disease, and have caused many deaths in China during recent years. But the natural history of enterovirus infection in children, especially asymptomatic children, is not yet clear. From April 2011 to May 2012, 505 stool and throat swab samples of children attending outpatients clinics in two hospitals were collected weekly to test for Enterovirus 71, Coxsackievirus A16, and other enterovirus nucleic acids by real-time RT-PCR. Two hundred sixty-four patients were enterovirus positive, the positive rate was 52.3%, 27.5% (22/80) in children without a rash and 56.9% (242/425) in children with a rash. Coxsackievirus A16 positive rate of male (24%, 61/254) was higher than that of female (15.2%, 26/171) (χ(2) = 4.87, P = 0.027). The highest positive rate of enterovirus infection was 63.5% in the 2-year-old age group. Comparing children with and without a rash, within the same age groups, no statistical difference was found (P > 0.05). The seasonal distribution of Enterovirus 71 had only one peak in May, but Coxsackievirus A16 had two peaks in April and October. In patients with a rash, the frequency of Enterovirus 71 was relatively high before July, and then that of Coxsackievirus A16 increased gradually. In the case of Enterovirus 71 and Coxsackievirus A16, stool specimens had a higher positive rate than throat swab specimens' (χ(2) = 3.88, P = 0.05; χ(2) = 15.13, P < 0.001). Enterovirus infection was more frequent in males 2-3 year-old children, with the implicated virus varying by season. Targeted prevention and control measures should be carried out.

Depressive symptoms and associated factors among older patients with arthritis: evidence from a community-based study in eastern China.

Introduction: Depressive symptoms are often experienced by patients with arthritis and are correlated with poor health outcomes. However, the association between depressive symptoms and multidimensional factors (sociodemographic characteristics, health conditions, health behaviors, and social support) among older patients with arthritis in China remains poorly understood. This study aimed to explore the prevalence of depressive symptoms in older patients with arthritis in eastern China and identify the associated factors. Methods: We analyzed data of 1,081 older patients with arthritis using secondary data from 2014 to 2020 from a community-based ongoing study initiated in 2014 in eastern China. The prevalence of depressive symptoms was calculated, and univariate and multilevel logistic regression analyses were used to identify the associated factors. Results: The mean age of older patients with arthritis was 69.16 ± 7.13 years; 42.92% were men and 57.08% were women. The prevalence of depressive symptoms in older patients with arthritis was 14.99% (95% confidence interval: 12.91-17.26%), about 1.8 times higher than that in older adults without arthritis (8.49%, p < 0.001). Multilevel logistic regression identified perception of poor economic status (odds ratio [OR] = 5.52, p < 0.001), multimorbidity (OR = 1.96, p = 0.001), limitations in activities of daily living (OR = 2.36, p = 0.004), and living alone (OR = 3.13, p = 0.026) as factors positively associated with depressive symptoms. Patients diagnosed with arthritis at an older age had lower odds of experiencing depressive symptoms (OR = 0.67, p = 0.046). Conclusion: Screening for depressive symptoms is essential among older patients with arthritis, especially those who perceive themselves as having a poor economic status, are diagnosed at an earlier age, have multimorbidity, have limitations in activities of daily living, and live alone. The associations of age at arthritis diagnosis and dietary behaviors with depressive symptoms require further research.

Estimation of scrub typhus incidence and spatiotemporal multicomponent characteristics from 2016 to 2023 in Zhejiang Province, China.

Background: China is one of the main epidemic areas of scrub typhus, and Zhejiang Province, which is located in the coastal area of southeastern China, is considered a key region of scrub typhus. However, there may be significant bias in the number of reported cases of scrub typhus, to the extent that its epidemiological patterns are not clearly understood. The purpose of this study was to estimate the possible incidence of scrub typhus and to identify the main driving components affecting the occurrence of scrub typhus at the county level. Methods: Data on patients with scrub typhus diagnosed at medical institutions between January 2016 and December 2023 were collected from the China Disease Control and Prevention Information System (CDCPIS). The kriging interpolation method was used to estimate the possible incidence of scrub typhus. Additionally, a multivariate time series model was applied to identify the main driving components affecting the occurrence of scrub typhus in different regions. Results: From January 2016 to September 2023, 2,678 cases of scrub typhus were reported in Zhejiang Province, including 1 case of reported death, with an overall case fatality rate of 0.04%. The seasonal characteristics of scrub typhus in Zhejiang Province followed an annual single peak model, and the months of peak onset in different cities were different. The estimated area with case occurrence was relatively wider. There were 41 counties in Zhejiang Province with an annual reported case count of less than 1, while from the estimated annual incidence, the number of counties with less than 1 case decreased to 21. The average annual number of cases in most regions fluctuated between 0 and 15. The numbers of cases in the central urban area of Hangzhou city, Jiaxin city and Huzhou city did not exceed 5. The estimated random effect variance parameters σ λ 2 , σ ϕ 2 , and σ ν 2 were 0.48, 1.03 and 3.48, respectively. The endemic component values of the top 10 counties were Shuichang, Cangnan, Chun'an, Xinchang, Pingyang, Xianju, Longquan, Dongyang, Yueqing and Qingyuan. The spatiotemporal component values of the top 10 counties were Pujiang, Anji, Pan'an, Dongyang, Jinyun, Ninghai, Yongjia, Xiaoshan, Yinwu and Shengzhou. The autoregressive component values of the top 10 counties were Lin'an, Cangnan, Chun'an, Yiwu, Pujiang, Longquan, Xinchang, Luqiao, Sanmen and Fuyang. Conclusion: The estimated incidence was higher than the current reported number of cases, and the possible impact area of the epidemic was also wider than the areas with reported cases. The main driving factors of the scrub typhus epidemic in Zhejiang included endemic components such as natural factors, but there was significant heterogeneity in the composition of driving factors in different regions. Some regions were driven by spatiotemporal spread across regions, and the time autoregressive effect in individual regions could not be ignored. These results that monitoring of cases, vectors, and pathogens of scrub typhus should be strengthened. Furthermore, each region should take targeted prevention and control measures based on the main driving factors of the local epidemic to improve the accuracy of prevention and control.