key: cord-0960151-f12v6bp0
authors: Pan, Q.; Gao, F.; Peng, R.; Li, M.
title: Epidemiological characteristics of patients with residual SARS-Cov-2 in Linyi, China
date: 2020-06-18
journal: nan
DOI: 10.1101/2020.06.16.20133199
sha: 23edb2b40263a1dc7bef5be1899d7d07cb8b338a
doc_id: 960151
cord_uid: f12v6bp0

Patients with 2019 novel Coronavirus infection are probably showing positive testing results again. In order to better treat these patients and provide basis for further control measures, we analyze the epidemiological outcomes and clinical features of patients with residual Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-Cov-2) in Linyi city. From January 23 to March 31 in 2020, epidemiological and clinical information of confirmed patients are collected for analysis. Stool and pharyngeal swab samples are collected for RT-PCR testing. 64 confirmed patients are included and 17 patients present re-positive testing after discharge. For these 17 patients, 70.59% are family aggregated, the interval between first time of negative testing and first time of re-positive testing is 11.82{+/-}3.42 days. There is no difference between patients with continued negative testing results and re-positive testing. After discharge, the interval between first time of negative testing and first time of re-positive testing is associated with severity of disease (p=0.013). Besides, the duration from first time to last time of re-positive testing is associated with exposure or contact history (p=0.049) and severity of disease (p=0.001). The analysis reveals epidemiological characteristics of patients with residual SARS-Cov-2 and provide basis for further control measures.

From December in past year, 2019 novel Coronavirus (2019-nCov) started to spread around the world, causing more than 7.11 million cases of infection and 406 thousand cases of death. The virus transmits from people to people, and causes severe acute respiratory disease 1 

Participants and data collection 64 patients confirmed by laboratory testing for 2019-nCoV are included in the study. All the patients discharge with at least two continued negative testing for SARS-Cov-2, then they are centralized isolation for observation. The following testing during isolation is performed by the Linyi People's Hospital or Linyi Centers for Disease Control and Prevention. The study ranges from January 23 to March 31 in 2020. Gender, age, exposure history to Hubei Province or contact with confirmed patients, onsets of symptoms, data of diagnosis, date of testing first negative, date of re-positive testing , severity of disease and other information were included for further analysis. All data were checked by two researchers (Q P and F G). The diagnosis, treatment and isolation for Coronavirus Disease 2019 (COVID-19) is according to the Chinese management guideline for COVID-19 (version 5.0) 3 . This study is approved by institutional review board of Linyi People's Hospital. The need for informed consent is waived.

Both stool and pharyngeal swab samples are collected for testing. The interval between . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)

The copyright holder for this preprint this version posted June 18, 2020. . https://doi.org/10.1101/2020.06.16.20133199 doi: medRxiv preprint two samples collection is not fixed. Real-time RT-PCR method 4 was used for laboratory confirmation of SARS-CoV-2 infection.

Chi-square test and ANOVA test were used to compare the difference where appropriate.

A two-sided α of less than 0.05 was considered statistically significant. SPSS 22.0 was used for statistical analysis. Table 1 (Table 1) , which means that patients with serious illness have a longer time in duration of re-positive testing.

This study focuses on 2019-nCoV infection in a city with a large population. We found there is no difference in the gender, age and exposure between patients with re-positive testing . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

The copyright holder for this preprint this version posted June 18, 2020. . https://doi.org/10.1101/2020.06.16.20133199 doi: medRxiv preprint and testing negative after discharge. This analysis indicated that population with residual SARS-Cov-2 are not special group. However, we find more than 70% patients are family aggregated. Along with previous study 2 , we deduce that contact control may effectively reduce exposure to SARS-Cov-2 and reduce the chance of re-positive testing. In our study, we find that patients with serious illness appear positive testing earlier. The reason maybe that serious illness resulted from more virus infections, and more residual SARS-Cov-2 remained in the body of these patients, which makes the positive testing appear easier and more likely. This reason is similar with previous report 5 . The analysis also indicates that even discharge from hospital with negative testing at least two times, some patients still carry residual SARS-Cov-2 and show repeatedly positive testing outcome for 22.44±13.61 days. For these patients, three weeks or longer time of isolation and continuous detection for SARS-Cov-2 after discharge is valuable 6 .

There are some limitations in this analysis. Our analysis mainly study the epidemiological and clinical characteristics of patients in Linyi city, the study is regional and crowd limited.

The duration of exposure or contact and the severity of imported patients from other cities are not detailed recorded. The testing collection is not performed day by day, which causes deviation to accurate calculation of interval and duration. In our study, we find patients with history of exposure to Hubei Province show a shorter day in positive duration after discharge. This means that exposure to Hubei is not necessarily infect more virus than contact with confirmed patients. Incomplete recording information maybe the reason for the difference in exposure or contact history. Besides, one case in the analysis is special.

He is 62 years old, has a poor basic health state and low immunity. Considering that the poor immunity affect the response of immune system to virus infection, he is excluded for this analysis. Thus, only one case older than 60 years is included in the study, leading limitation to age comparison.

Most patients with re-positive testing are family aggregated, more than three week isolation and observation are necessary for them. Patients with serious illness are earlier to appear re-positive testing, and have a longer time in positive testing for SARS-Cov-2 after . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

The copyright holder for this preprint this version posted June 18, 2020. . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

The copyright holder for this preprint this version posted June 18, 2020. . https://doi.org/10.1101/2020.06.16.20133199 doi: medRxiv preprint Table 1 Relationship between clinical features and positive outcomes Interval refers to range between first time of negative testing and first time of re-positive testing.

Duration refers to range between first time and last time of re-positive testing after discharge. * P value for Asymptomatic+Mild vs Severe+Critic is 0.005; ** P value for Asymptomatic+Mild vs Severe+Critic is 0.037, for Common vs Severe+Critic is 0.006.

Interval ( . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)

The copyright holder for this preprint this version posted June 18, 2020. . https://doi.org/10.1101/2020.06.16.20133199 doi: medRxiv preprint

A familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-to-person transmission: a study of a family cluster

Pathological evidence for residual SARS-CoV-2 in pulmonary tissues of a ready-for-discharge patient

Guidelines for the Diagnosis and Treatment of Novel Coronavirus (2019-nCoV) Infection by the National Health Commission (Trial Version 5

Clinical Features of Maintenance Hemodialysis Patients with 2019 Novel Coronavirus-Infected Pneumonia in Wuhan, China

Epidemiological characteristics of SARS-CoV-2 infections in Shaanxi

Isolation, quarantine, social distancing and community

The authors declare no competing interests.Supplementary Table 1 Difference between patients with re-positive and negative testing Positive duration refer to range from onsets of symptom or to last time of positive testing, for asymptomatic patients, the range is from first positive laboratory testing to last time of positive testing. . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

The copyright holder for this preprint this version posted June 18, 2020. Interval refers to range between first time of negative testing and first time of re-positive testing. Duration1 refers to range between onsets of symptom and the last time of positive testing in hospital, for asymptomatic patients, the range is from first positive laboratory testing to last time of positive testing.Duration 2 refers to range between first time and last time of re-positive testing after discharge.. CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

The copyright holder for this preprint this version posted June 18, 2020. . https://doi.org/10.1101/2020.06.16.20133199 doi: medRxiv preprint . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)The copyright holder for this preprint this version posted June 18, 2020. . https://doi.org/10.1101/2020.06.16.20133199 doi: medRxiv preprint