Re-Positive Rate Of Discharged COVID-19 Patients During 0801 COVID-19 Outbreak In Jiyang District,Sanya City,Hainan Province

Objective:This study investigated the situation of re-positive infected patients discharged from Jiyang District,Sanya City,Hainan Province,during the Hainan0801 COVID-19 outbreak.We calculated the re-positive rate of infected patients.Further we captured the characteristics of infected patients in the recovery period,and analyzed risk factors of re-positive and re-positive time interval as well as the severity of disease and length of hospitalization after re-positive.Methods:In this study,infected patients in Jiyang District,Sanya City,Hainan Province,from the 0801 COVID-19 outbreak were selected as the study participants,and information on hospital discharges from August 13 to September 9,2022 was collected.Data were collected and analyzed using Excel and SPSS software.The c~2test and Kruskal-Wallis test were used for one-way analysis.The Kaplan-Meier method was used to calculate the 7-day cumulative re-positive rate of hospital discharge and Log-Rank test was performed on the results.Logistic regression model and linear regression model were used for multi-factor analysis to investigated the risk factors of re-positive and re-positive time interval.Result:5340 individuals were included in analyze(with 833 individuals nucleic acid re-positive after discharged,and 4507 individuals were not).The result indicated that the re-positive rate in our study was 15.6%(95%CI:14.6-16.6).The results of logistic regression showed that age and length of hospitalization were independent factors for re-positive(both P-values<0.050).The risk of re-positive was low in children aged 0-8 years(OR:0.706[95%CI:0.533-0.935]),that decreased with increasing length of hospitalization gradually(P-value<0.050).The cumulative re-positive rate at 7 days post-discharge follow-up was lowest(8.8%[95%CI:6.3-11.8%])in the early phase(August 1 to August 7,2022)and highest(27.6%[95%CI:22.2-33.5%])in the last phase(August 22 and after).The length of hospitalization was an independent factor of time interval of re-positives,and the time interval between re-positives was longer for infected patients with short hospitalization(β:0.930[95%CI:0.471-1.389]).The majority of re-infected patients had fewer symptoms and shorter hospital stay than the first admission,and there was no difference between age groups in terms of whether symptoms worsened after re-positive and whether the hospital stay was prolonged.Conclusion:The results showed that the re-positive rate in Jiyang District was15.6%(95%CI:14.6-16.6%).Children aged 0-8 years had a low risk of re-positive,and patients with short hospitalization had a high risk of re-positive and a long interval of re-positive.Most of the patients had milder symptoms and shorter hospitalization time during re-positive hospitalization compared to the initial infection.