Objective: To investigate an outbreak of beta-hemolytic streptococcal tonsillitis in a hospital.
Methods: A case-control study was conducted with a self-made questionnaire to collect the risk factors. Univariate and multivariate logistic regression model were used to explore the relationship between risk factors and morbidity.
Results: 74 cases were occurred during the outbreak with patients aged mainly between 20-30 and more females than males. Most cases appeared abrupt onset between Aug., 20-22. All the patients were hospital workers, with majority as nurses and doctors from the operating room, department of anesthesiology and surgical related departments (71.62%). All patients shared the same experience-eating lunch in the dining room on Aug 19(odds ratio 6.67, 95% confidence interval 1.92-23.23). Beta-hemolytic streptococci was observed from cultures of the throats from the patients.
Conclusion: The outbreak was an explosive epidemic of tonsillitis in a hospital, caused by beta-hemolytic streptococci. Food provided from the dining room attached to the operating theater on August, 19 seemed to be the risk factor.