Time series analysis of reported cases of hand, foot, and mouth disease from 2010 to 2013 in Wuhan, China.

BACKGROUND: Hand, foot, and mouth disease (HFMD) is an infectious disease caused by a group of enteroviruses, including Coxsackievirus A16 (CVA16) and Enterovirus A71 (EV-A71). In recent decades, Asian countries have experienced frequent and widespread HFMD outbreaks, with deaths predominantly among children. In several Asian countries, epidemics usually peak in the late spring/early summer, with a second small peak in late autumn/early winter. We investigated the possible underlying association between the seasonality of HFMD epidemics and meteorological variables, which could improve our ability to predict HFMD epidemics. METHODS: We used a time series analysis composed of a spectral analysis based on the maximum entropy method (MEM) in the frequency domain and the nonlinear least squares method in the time domain. The time series analysis was applied to three kinds of monthly time series data collected in Wuhan, China, where high-quality surveillance data for HFMD have been collected: (i) reported cases of HFMD, (ii) reported cases of EV-A71 and CVA16 detected in HFMD patients, and (iii) meteorological variables. RESULTS: In the power spectral densities for HFMD and EV-A71, the dominant spectral lines were observed at frequency positions corresponding to 1-year and 6-month cycles. The optimum least squares fitting (LSF) curves calculated for the 1-year and 6-month cycles reproduced the bimodal cycles that were clearly observed in the HFMD and EV-A71 data. The peak months on the LSF curves for the HFMD data were consistent with those for the EV-A71 data. The risk of infection was relatively high at 10 °C ≤ t < 15 °C (t, temperature [°C]) and 15 °C ≤ t < 20 °C, and peaked at 20 °C ≤ t < 25 °C. CONCLUSION: In this study, the HFMD infections occurring in Wuhan showed two seasonal peaks, in summer (June) and winter (November or December). The results obtained with a time series analysis suggest that the bimodal seasonal peaks in HFMD epidemics are attributable to EV-A71 epidemics. Our results suggest that controlling the spread of EV-A71 infections when the temperature is approximately 20-25 °C should be considered to prevent HFMD infections in Wuhan, China.

Application of seasonal auto-regressive integrated moving average model in forecasting the incidence of hand-foot-mouth disease in Wuhan, China.

Outbreaks of hand-foot-mouth disease (HFMD) have occurred many times and caused serious health burden in China since 2008. Application of modern information technology to prediction and early response can be helpful for efficient HFMD prevention and control. A seasonal auto-regressive integrated moving average (ARIMA) model for time series analysis was designed in this study. Eighty-four-month (from January 2009 to December 2015) retrospective data obtained from the Chinese Information System for Disease Prevention and Control were subjected to ARIMA modeling. The coefficient of determination (R 2), normalized Bayesian Information Criterion (BIC) and Q-test P value were used to evaluate the goodness-of-fit of constructed models. Subsequently, the best-fitted ARIMA model was applied to predict the expected incidence of HFMD from January 2016 to December 2016. The best-fitted seasonal ARIMA model was identified as (1,0,1)(0,1,1)12, with the largest coefficient of determination (R 2=0.743) and lowest normalized BIC (BIC=3.645) value. The residuals of the model also showed non-significant autocorrelations (P Box-Ljung (Q)=0.299). The predictions by the optimum ARIMA model adequately captured the pattern in the data and exhibited two peaks of activity over the forecast interval, including a major peak during April to June, and again a light peak for September to November. The ARIMA model proposed in this study can forecast HFMD incidence trend effectively, which could provide useful support for future HFMD prevention and control in the study area. Besides, further observations should be added continually into the modeling data set, and parameters of the models should be adjusted accordingly.

Postpartum practices of puerperal women and their influencing factors in three regions of Hubei, China.

BACKGROUND: 'Sitting month' is a Chinese tradition for women's postpartum custom. The present study aims to explore the postpartum dietary and health practices of puerperal women and identify their influential factors in three selected regions of Hubei, China. METHODS: A cross-sectional retrospective study was conducted in the selected urban, suburban and rural areas in the province of Hubei from 1 March to 30 May 2003. A total of 2100 women who had given birth to full-term singleton infants in the past two years were selected as the participants. Data regarding postpartum practices and potentially related factors were collected through questionnaire by trained investigators. RESULTS: During the puerperium, 18% of the participants never ate vegetables, 78.8% never ate fruit and 75.7% never drank milk. Behaviour taboos such as no bathing, no hair washing or teeth brushing were still popular among the participants. About half of the women didn't get out of the bed two days after giving birth. The average time they stayed in bed during this period was 18.0 h. One third of them didn't have any outdoor activities in that time periods. The educational background of both women and their spouses, location of their residence, family income, postnatal visit, nutrition and health care educational courses were found to be the influencing factors of women's postpartum practices. CONCLUSION: Traditional postpartum dietary and health behaviours were still popular among women in Hubei. Identifying the factors associated with traditional postpartum practices is critical to develop better targeting health education programs. Updated Information regarding postpartum dietary and health practices should be disseminated to women.

Self-reported health problems related to traditional dietary practices in postpartum women from urban, suburban and rural areas of Hubei province, China: the 'zuò yuèzi'.

BACKGROUND AND OBJECTIVES: We aimed to investigate the prevalence of maternal health problems in the postpartum period and their association with traditional Chinese postpartum diets and behaviours in three selected regions in Hubei province, China. METHODS AND STUDY DESIGN: A cross-sectional study was conducted in urban, suburban and rural areas. A total of 2100 women who had given birth to full-term single infants in the past two years were enrolled. Their postpartum diet, personal behaviours, and health problems were surveyed by trained interviewers. RESULTS: During the puerperium women consumed plentiful eggs, fish, poultry and meats; however, fruit, vegetable and milk consumption were limited. A high prevalence of health problems potentially related to pregnancy and the puerperium were found. At least one such problem was reported by 59.3% of women. The putative postpartum problems were backaches (29.6%), arthralgia or leg clonus (12.7%), breast problems (19.6%), constipation (18.7%), haemorrhoids (11.7%), dizziness or headaches (14.8%), anaemia (10.0%). Multiple logistic regression analysis showed that leafy vegetable intake and frequent recipe change in the puerperium were positively associated with less anal diseases. Bathing or hair washing did not increase the risk of maternal infection as belief would have suggested. However, bathing was a risk factor for backache or arthralgia, and tooth brushing was a risk factor for bleeding gums. Excessive housework was a risk factor for anal diseases and disordered uterine involution. CONCLUSION: Postpartum maternal health problems were prevalent in Hubei province. These were in part associated with postpartum traditional Chinese diets and behaviours.