Is reinfection possible after recovery from COVID-19?

• Published in: Hong Kong medical journal = Xianggang yi xue za zhi Vol. 26; no. 3; pp. 264 - 265
• Main Authors: Law, S K, Leung, A W N, Xu, C
• Format: Journal Article
• Language: English
• Published: China Hong Kong Academy of Medicine 01-06-2020
• Subjects: Betacoronavirus - isolation & purification; Betacoronavirus - physiology; Clinical Laboratory Techniques - methods; Coronavirus Infections - diagnosis; Coronavirus Infections - virology; Coronaviruses; COVID-19; COVID-19 Testing; Disease transmission; Humans; Infections; Laboratories; Pandemics; Pneumonia, Viral - diagnosis; Pneumonia, Viral - virology; Polymerase chain reaction; Recurrence; SARS-CoV-2; Severe acute respiratory syndrome coronavirus 2; Specimen Handling - methods; Specimen Handling - standards; Viral infections; Virus Physiological Phenomena; Viruses; Hong Kong; China
• ISSN: 1024-2708; 2226-8707
• DOI: 10.12809/hkmj208601

Among 111 recovered patients, 5% in China and 10% in South Korea have tested positive again.1 2 Typically, after recovery from a viral infection, the body produces antibodies that can resist reinfection from the same virus.3 There is evidence that COVID-19 reinfection is not possible within 7 to 10 days.4 A Chinese study on COVID-19 involving primates showed no viral replication in all primary tissue compartments at 5 days post-reinfection, indicating that the primary infection of SARS-CoV-2 could prevent subsequent infections.5 Positive reverse transcription polymerase chain reaction test results from the patients who have recovered from COVID-19 are possibly attributed to: (i) The virus persisting within body. The sample may not be collected widely and deeply enough to include the virus, resulting in a negative result.11 Furthermore, the virus binds to the angiotensin-converting enzyme 2 receptor and remains in the throat, but the test includes only the upper respiratory tract where the amount of virus has been reduced.12 When clinical symptoms are stable, the virus can still spread and infect different organs such as the spleen, hilar lymph nodes, kidneys, liver, and brain; in such cases deep throat saliva test may not be able to detect SARS-CoV-2 infection.13 There is currently no supporting evidence for COVID-19 reinfection after recovery. In accordance with the advice of the World Health Organization, patients with no clinical symptoms can be discharged from the hospital if they test negative for SARS-CoV-2 infection at least twice after a 24-hour interval.14 Author contributions All authors contributed to the concept of the study, acquisition and analysis of the data, drafting of the manuscript, and critical revision of the manuscript for important intellectual content.