Epidemiological and clinical differences between sexes and pathogens in a three-year surveillance of acute infectious gastroenteritis in Shanghai.

Acute infectious gastroenteritis cases in Shanghai, reported over three years, were analyzed. Pathogens were identified in 1031 patients; of these, 725 and 306 were bacterial and viral cases, respectively. Vibrio parahemolyticus and Salmonella were the dominant bacteria, and Caliciviridae and Reoviridae were the dominant viral families in the local area. The acute gastroenteritis epidemic peaks appeared in August and January, which represented the active peak periods of bacteria and viruses, respectively. Logistic regression analyses with sex stratification showed that abdominal pain, fever and ingestion of unsafe food at restaurants were independent factors more frequently associated with bacterial gastroenteritis irrespective of sex; red cell-positive fecal matter was associated with bacterial gastroenteritis with an odds ratio (OR) of 3.28 only in males; and white blood cell count was associated with bacterial gastroenteritis with an OR of 1.02 only in females. Pathogen stratification showed that age, vomiting and red cell-positive fecal matter were associated with males with ORs of 0.99, 0.61 and 1.71, respectively, in bacterial gastroenteritis; and the migrant ratio was higher in males with an OR of 2.29 only in viral gastroenteritis. In conclusion, although bacterial and viral gastroenteritis shared many features, epidemiological and clinical factors differed between sexes and pathogens.

Impact of meteorological factors on the incidence of childhood hand, foot, and mouth disease (HFMD) analyzed by DLNMs-based time series approach.

BACKGROUND: Hand, foot, and mouth disease (HFMD) has become an emerging infectious disease in China in the last decade. There has been evidence that meteorological factors can influence the HFMD incidence, and understanding the mechanisms can help prevent and control HFMD. METHODS: HFMD incidence data and meteorological data in Minhang District, Shanghai were obtained for the period between 2009 and 2015. Distributed lag non-linear models (DLNMs) were utilized to investigate the impact of meteorological factors on HFMD incidence after adjusting for potential confounders of long time trend, weekdays and holidays. RESULTS: There was a non-linear relationship between temperature and HFMD incidence, the RR of 5th percentile compared to the median is 0.836 (95% CI: 0.671-1.042) and the RR of 95th percentile is 2.225 (95% CI: 1.774-2.792), and the effect of temperature varied across age groups. HFMD incidence increased with increasing average relative humidity (%) (RR = 1.009, 95% CI: 1.005-1.015) and wind speed (m/s) (RR = 1.197, 95% CI: 1.118-1.282), and with decreasing daily rainfall (mm) (RR = 0.992, 95% CI: 0.987-0.997) and sunshine hours (h) (RR = 0.966, 95% CI: 0.951-0.980). CONCLUSIONS: There were significant relationships between meteorological factors and childhood HFMD incidence in Minhang District, Shanghai. This information can help local health agencies develop strategies for the control and prevention of HFMD under specific climatic conditions.

The population-based health effect of hand, foot and mouth disease in children in Shanghai.

BACKGROUND: An effective enterovirus 71 (EV71) vaccine is needed to control the annual outbreaks of hand, foot and mouth disease (HFMD) in China. Adequate epidemiologic data relating to HFMD are needed to make decisions about appropriate public health interventions and implementation of the new EV71 vaccine. METHODS: We analyzed the population-based epidemiologic characteristics, clinical outcome and laboratory investigation of the 2011 HFMD outbreak in children based on the citywide surveillance system in Shanghai. RESULTS: The incidence rate of HFMD was 25.8 per 1000 in children <10 years of age in Shanghai in 2011, ranging from 2.5 per 1000 in the age group 7 to 9.9 years to 48.4 per 1000 in the age group 3 to 3.9 years. Children 1 to 1.9 years were at the highest risk of developing severe complications and most susceptible to HFMD. Boys and migrant children had significantly increased risks of contracting HFMD and developing severe disease. More institutional clusters/outbreaks occurred in the winter peak months than in the summer peak months. Migrant young children played a central role in the spread of HFMD in the community. EV71 was identified in 39.7% of mild HFMD outpatients, 47.4% of hospitalized patients, 92.1% of severe inpatients with complications, 50% of outbreaks and 38.8% of clusters in institutions. CONCLUSION: HFMD and EV71 infections have a significant health effect on Shanghai children.