Objective To analyze the clinical symptoms and epidemiological characteristics of infant botulism cases admitted to two large children's hospitals in Beijing from May 2015 to April 2021 and provide evidence for the detection, diagnosis, treatment and prevention of infant botulism.

Methods The information of 18 cases of infant botulism admitted to two children's hospitals in Beijing during this period, including age, sex, time of onset, area distribution, clinical symptoms, treatment, laboratory toxin detection and serotype of isolated strains were collected for a descriptive analysis.

Results The male to female ratio of the 18 cases was 2.00∶1. The cases were aged 3-8 months, the median age was 6 months. The cases mainly occurred in Hebei and Beijing, and the case count increased year by year. The annual case count was lowest in the first quarter, and it was similar in other quarters. General fatigue and constipation were the most common clinical symptoms. Serotype test results showed that serotype B was predominant, accounting for 94.00% (17 cases). Real-time fluorescence quantitative polymerase chain reaction (PCR) and mouse test were the most sensitive methods, followed by culture and isolation.

Conclusion Real time PCR has the advantage of fast and simple, and can be used as a routine detection method. If case has unexplained general fatigue and constipation, infant botulism should be considered in clinical diagnosis and treatment and case's stool and serum samples should be taken for testing. In the area with high incidence of infant botulism, it is necessary to conduct or strengthen professional training in physicians to improve their understanding and diagnosis of infant botulism. Meanwhile, the timely stockpile of serotype specific antitoxin should be made. The early use of adequate botulism antitoxin in treatment is a key measure to save life, and ventilator is needed to assist breathing when necessary.