Study design and participants
We enrolled patients from Jan 20 to Feb 26, 2020, at Department of Infectious Disease，the Fifth Affiliated Hospital, Sun Yat-sen University, in Zhuhai, Guangdong Province, China. Patients diagnosed with SARS-CoV-2 infection were screened according to WHO interim guidance3. The inclusion criteria were as follows: (1) between 18 and 65 years old, (2) being SARS-CoV-2 RNA positive, (3) willing to provide respiratory swabs, and (4) using WeChat. The criteria for exclusion were as follows: (1) confirmed as severe COVID-19 pneumonia, (2) rapidly deteriorated into severe, (3) complicated with malignant tumors or compromised immune system, and (4) unable to make voice call daily by WeChat.
A confirmed case with SARS-CoV-2 infection was defined as a positive result to high-throughput sequencing or real-time reverse-transcriptase polymerase-chain-reaction (RT-PCR) assay for nasal or pharyngeal swab specimens1, 7. The incubation period was defined as the duration from the contact of the transmission source to the onset of symptoms. Exposure history was defined as exposure to people with confirmed SARS-CoV-2 infection or to the Wuhan area. Respiratory samples were collected every 1–2 days until two sequential negative results were obtained.
The study was approved by the Medical Ethical Committee of the Fifth Affiliated Hospital of Sun Yat-sen University (approval number L076-1) and informed consent was obtained from participants. Both of the test and the control groups were treated with standard therapy and routine ward-round, according to the guideline of diagnosis and treatment of SARS-CoV-2 infection (standard version)8. All changes in patients' conditions were monitored, recorded and responded timely.
Aiming to explore new electronic communication mode to treat the infectious disease, we grouped patients of the test group into three subgroups, providing additional high-quality on-line ward-round and psychological care using WeChat voice calls.
The first group (5 minutes group) was given an extra on-line ward-round by WeChat voice call for 5 minutes once daily. In the 5 minutes patients could communicate with the doctor in charge about the disease progression. The second group (10 minutes group) was given an extra on-line ward-round by We-Chat for 10 minutes once daily. In the 10 minutes patients could communicate with the doctor in charge about the disease progression, and the extent and future outlook of the disease. The third group (10 minutes + minutes group) was given an extra 10 minutes’ on-line talk every three days, which could gather more detailed information of the disease. The fourth group, also the blank controlled group, was just treated with standard therapy. Respecting patient consent, all patients were free to choose consent or opting-out.
The epidemiological characteristics (including recent exposure history), clinical symptoms and signs and laboratory findings were extracted from electronic medical records. Computed tomography was used as radiologic assessment. Laboratory assessments consisted of complete blood count, blood chemistry, coagulation test, liver and renal function, electrolytes, reactive protein, procalcitonin, lactate dehydrogenase and creatine kinase. All data were checked by two physicians (ZF and ZG) and a third researcher (JL) adjudicated any difference in interpretation between the two primary reviewers.
The primary endpoint was the duration of positive-to-negative conversion of SARS-CoV-2 RNA diagnosed by the NAT (nucleic acid testing). It was the time from laboratory conformed positive to negative of SARS-CoV-2 RNA result after two sequential negative respiratory tract sample results. The interval between the two negative results must be more than 24 hours.
We used SPSS (version 19.0) for all analyses. Continuous variables were presented as median (interquartile range) and compared with Mann-Whitney U test. Categorical variables were presented as number (%) and compared by Chi-square test or Fisher’s exact test.