Efficacy of Serology Testing in Predicting Reinfection in Patients With SARS-CoV-2

Disaster Med Public Health Prep. 2021 Apr;15(2):e29-e31. doi: 10.1017/dmp.2020.216. Epub 2020 Jun 24.

Abstract

In many parts of the United States, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cases have reached peak infection rates, prompting administrators to create protocols to resume elective cases. As elective procedures and surgeries get scheduled, ambulatory surgery centers (ASCs) must implement some form of widespread testing in order to ensure the safety of both the ASC staff and the patients being seen. The US Centers for Disease Control and Prevention (CDC) recently announced the approval of new serological testing for SARS-CoV-2, a test that can indicate the presence of IgM and IgG antibodies in the serum against viral particles. However, the possibility for reinfection raises questions about the utility of this new serological test, as the presence of IgG may not correspond to long-term immunity. SARS-CoV-2 has been known to form escape mutations, which may correspond to a reduction in immunoglobulin binding capacity. Patients who develop more robust immune responses with formation of memory CD8+ T-cells and helper CD4+ T-cells will be the most equipped if exposed to the virus, but, unfortunately, the serology test will not help us in distinguishing those individuals. Given the inherent disadvantages of serological testing, antibody testing alone should not be used when deciding patient care and should be combined with polymerase chain reaction testing.

Keywords: COVID-19; SARS-CoV-2; immunity; serology testing.