ABSTRACT
Objective To investigate the characteristics of outbreaks of acute gastroenteritis caused by sapovirus infection among primary school students in Yangzhou. Methods An on-site epidemiological investigation was carried out to analyze the clinical symptoms and risk factors of epidemic transmission. Samples of patients were collected for nucleic acid detection of sapovirus. Follow-up observations were carried out on cases with positive detection to explore the duration of intestinal detoxification of sapovirus infection. Samples of close contacts without clinical symptoms were collected to analyze recessive infection status. Results A total of 30 cases were reported from two outbreaks of sapovirus infection. As a main symptom, the incidence rate of vomiting was 93.33%. The duration of intestinal detoxification of the cases was 3 to 19 days, with an average of 11.12 days. The rate of recessive infection was 26.32%. The risk factor for sapovirus infection was exposure to vomit or feces within 1 meter (OR=12.94, 95%CI 1.19-140.37), and the protective factor was washing hands before eating (OR=0.064, 95%CI 0.007-0.56). Conclusion The main symptom of sapovirus infection was vomiting, with a high rate of recessive infection and a long detoxification period. It is easy to cause an outbreak in primary schools. Exposure to vomit or feces within 1 meter could increase the risk of sapovirus infection. Washing hands before eating could reduce the risk of sapovirus infection.
ABSTRACT
Objective@#To explore the duration of intestinal detoxification and its related factors infected with Norovirus, and to provide scientific evidences for the prevention and control of acute gastroenteritis caused by Norovirus in the future.@*Methods@#Follow up and sampling program on 115 employees in a restaurant outbreak of Norovirus in Chengdu in 2017 was carried out. Anal swab was collected every 3 d or 7 d for nucleic acid detection, and the experimental results were statistically analyzed.@*Results@#The positive rates of Norovirus in restaurant employee were 14.78%, 7.89%, 3.51% and 0.88% on the 7th, 11th, 17th and 24th day, respectively. During the follow-up period, the positive rates of Norovirus decreased as time increased. The positive rate of all employees was up to 14.78% on the 7th day. The positive rates had no significant difference between different sex and between different types of work. The duration of detoxification averaged 14.94 days and the maximum of detoxification time was on 28 days. The detoxification period of treatment case was shorter than that of asymptomatic carriers.@*Conclusions@#There were asymptomatic carriers in restaurant employees during the outbreak of Norovirus that their role as a source of infection in the transmission of Norovirus should not be neglected. In the treatment of the epidemic, we should strengthen the sampling and testing of practitioners, and strictly implement isolation measures for positive detection.