Surveillance of hand, foot, and mouth disease in mainland China (2008-2009).

OBJECTIVE: Since HFMD was designated as a class C communicable disease in May 2008, 18 months surveillance data have been accumulated to December 2009. This article was to describe the distribution of HFMD for age, sex, area, and time between 2008 and 2009, to reveal the characteristics of the epidemic. METHODS: We analyzed weekly reported cases of HFMD from May 2008 to December 2009, and presented data on the distribution of age, sex, area and time. A discrete Poisson model was used to detect spatial-temporal clusters of HFMD. RESULTS: More than 1 065 000 cases of HFMD were reported in Mainland China from May 2008 to December 2009 (total incidence: 12.47 per 10 000). Male incidence was higher than female for all ages and 91.9% of patients were <5 years old. The incidence was highest in Beijing, Shanghai, Zhejiang and Hainan. The highest peak of HFMD cases was in April and the number of cases remained high from April to August. The spatial-temporal distribution detected four clusters. CONCLUSION: Children <5 years old were susceptible to HFMD and we should be aware of their vulnerability. The incidence was higher in urban than rural areas, and an annual pandemic usually starts in April.