Abstract
Background : Severe acute respiratory syndrome coronavirus 2
(SARS-CoV-2) test could be positive for a second time in some cases,
after recovery from their first coronavirus disease 2019 (COVID-19)
episode. However, causes of this re-positive test has not been fully
understood. In this paper, the original studies with re-positive
COVID-19 patients in their study population were discussed.
Methods : Scopus, PubMed, Embase, and Cochrane databases were
searched and the retrieved records underwent title/abstract and
full-text screenings. Three independent researchers extracted the data
of the studies.
Results : The systematic search yielded 16 case-control, cohort,
and cross-sectional studies. Data of 10,475 patients were included; 489
(4.67%) of them classified as re-positive. The female percentage and
mean age for re-positive and non-re-positive groups were 56.82% and
50.0 ± 18.0, and 55.91% and 46.6 ± 17.1, respectively. The rate of
symptom presentation upon second positive test turned out to be 20.0%,
with the most common symptoms being cough (68.2%), fever (31.8%), and
fatigue (22.7%). Hypertension (15.9%) accounted for the most common
underlying disease in the re-positive group. In 33/46 (71.7%) of the
re-positive patients, computed tomography (CT) abnormalities were
resolved to some extent.
Conclusion: A re-positive SARS-CoV-2 test is possible within a
few weeks after recovery, although it does not necessarily indicate a
re-infection. Other reasons could lead to a re-positive test such as
reactivation of the virus that persisted in the body from the previous
COVID-19 episode and testing errors. Clinical features such as symptoms
and imaging could assist in identifying re-infections.