Antibody tests may be effective in indicating past infection with COVID-19

Added July 14, 2020

Citation: Deeks JJ, Dinnes J, Takwoingi Y, et al. Antibody tests for identification of current and past infection with SARS‐CoV‐2. Cochrane Database of Systematic Reviews 2020(6).CD013652.

What is this? Efficient early detection and diagnosis of patients with COVID-19 infection is important.

In this Cochrane review, the authors searched for studies on the diagnostic accuracy of antibody tests (IgA, IgG, IgM) to determine if a person has SARS-CoV-2 infection or has previously had SARS-CoV-2 infection. They did not restrict their searches by language of publication but restricted their search to articles published between 2019 and 2020 and did the search on 27 April 2020. They included 54 studies from Asia (38), Europe (15) and both the USA and China (1). They also identified an additional 34 ongoing studies and 3 articles, which are awaiting assessment.

What works: At the time of this review, the included studies showed that antibody tests are likely to play a useful role in detecting previous SARS-CoV-2 infection, if used 15 or more days after the onset of symptoms in people who were hospitalised due to COVID-19.

The review authors noted that the quality of the studies limited their confidence in the validity of their findings. However, specificity was generally high so that a positive result was likely to indicate previous infection. Sensitivity was variable so tests may be less effective at excluding previous infection.

What doesn’t work: Nothing noted, but it seemed that point of care tests were not as effective as laboratory managed ones.

What’s uncertain: At the time of this review, the comparative effectiveness of different forms of the test, the effectiveness of antibody tests in people who were never admitted to hospital, and the duration of antibody rises remain uncertain.


Disclaimer: This summary has been written by staff and volunteers of Evidence Aid in order to make the content of the original document accessible to decision makers who are searching for the available evidence on the coronavirus (COVID-19) but may not have the time, initially, to read the original report in full. This summary is not intended as a substitute for the medical advice of physicians, other health workers, professional associations, guideline developers, or national governments and international agencies. If readers of this summary think that the evidence that is presented within it is relevant to their decision-making they should refer to the content and details of the original article, and the advice and guidelines offered by other sources of expertise, before making decisions. Evidence Aid cannot be held responsible for any decisions made about the coronavirus (COVID-19) on the basis of this summary alone.