Objective:
To analyze the characteristics of a norovirus outbreak in a kindergarten, and factors affecting the detoxification time, so as to provide a scientific basis for targeted control measures.
Methods:
On February 24,2023, the basic personal information, clinical manifestations,morbidity and treatment of 16 kindergarten cases with a norovirus outbreak in Wuhan were collected. Anal swabs were collected every 7 d after the outbreak to detect norovirus. Chisquare test was used for comparison of intergroup rates. The comparison of detoxification time between different groups was conducted by Logrank test, and the influencing factors of detoxification time in cases were analyzed by Cox multiple regression analysis.
Results:
From February 19-28, 2023, a total of 18 cases were reported and 16 of them participated in the detoxication time monitoring. In the first, second, third and fourth sampling after the outbreak, the positive rates were 60.00%, 100.00%, 75.00% and 0, respectively. The reverse transcriptionpolymerase chain reaction cycle threshold (Ct values) were (25.83±5.74, 28.83±5.55, 36.13±4.30), and undetected, respectively. The median time of detoxification was 19.42 d with 95%CI=(18.21-20.64)d. The results of Cox regression showed that the detoxication time was shorter in the treatment group than in the nontreatment group[HR(95%CI)=5.09(1.39-18.58), P<0.05].
Conclusion
Children infected with norovirus has a long duration of detoxification,and case management, which could be shortened by drugs, and disinfection should be strengthened after the case returned to school.