Risk factors for hand, foot, and mouth disease and herpangina and the preventive effect of hand-washing.

BACKGROUND: Hygiene and social distancing are recommended control measures for hand, foot, and mouth disease (HFMD) and herpangina. However, empirical data to support this recommendation are limited. METHODS: During an outbreak of HFMD and herpangina due to infection by the human enterovirus 71, we defined a case as a vesicular papular rash on the hands, feet, buttocks, or oral mucosa and onset from April 30 to June 26, 2008. We selected 176 HFMD and herpangina case-children and a stratified random sample of 201 asymptomatic control-children; frequency matched according to residency status. We administered a questionnaire to the parents about their children's exposures and hygienic behaviors. RESULTS: Risk factors for HFMD and herpangina included playing with neighborhood children (odds ratio [OR]: 11 [95% confidence interval (CI): 6.2-17]), visiting an outpatient clinic for another reason ≤ 1 week before onset (OR: 20 [95% CI: 5.0-88]), and community exposures to crowded places (OR: 7.3 [95% CI: 4.1-13]). By using a score summarizing responses to 4 hand-washing questions, we found that 50% of the case-children and 2.5% of control-children had a poor score of 1 to 3, whereas 12% of the case-children and 78% of control-children had a good score of ≥ 7 (OR: 0.00069 [95% CI: 0.0022-0.022]) after we adjusted for residency, age, and community exposures by using logistic regression. CONCLUSIONS: Hand-washing by preschool-aged children and their caregivers had a significant protective effect against community-acquired HFMD and herpangina from the human enterovirus 71 infection.

An outbreak of coxsackievirus A16 infection: comparison with other enteroviruses in a preschool in Taipei.

BACKGROUND/PURPOSE: The transmission rate of enteroviruses in young children remains unclear. Therefore, we carried out active surveillance in preschool children to investigate the transmission rate and clinical manifestation of enteroviruses. METHODS: From September 2006 to December 2008, we monitored infectious diseases in children 2(-3 years of age) in a preschool in Taipei. If any child had a febrile illness or symptoms/signs of enteroviral infection [e.g. herpangina or hand-foot-and-mouth disease (HFMD)], we performed viral isolation and enterovirus polymerase chain reaction. VP1 sequencing was performed to define their serotypes. We also collected clinical data and analyzed transmission rates. RESULTS: There were eight episodes of enterovirus infection during the study period. The serotypes included coxsackievirus A4 (CA4), CA2 and CA16. The transmission rates of CA4 and CA2 among children in same class were 26% and 35%, respectively. Between November 28 and December 12, 2008, 13/21 (61.9%) children contracted herpangina and/or HFMD. The average age was 2.82 (range, 2.43-3.39) years. CA16 was detected in 10/13 (76.9%) of the throat swabs by polymerase chain reaction VP1 genotyping. Compared with previous CA2 and CA4 outbreaks, CA16 had a significantly higher transmission rate (p = 0.035) and resulted in more cases of HFMD (p < 0.001). The transmission duration of coxsackie A viruses within the same class ranged from 12 to 40 days. CONCLUSION: Compared with CA2 and CA4, CA16 infections resulted in more cases of HFMD and had significantly higher transmission rates in preschoolers.