Authors
Benny PV, Chief Editor, Kerala Medical Journal
Abstract
Background: The recurrence of SARS-CoV-2 infection, encompassing reactivation or reinfection, poses a significant and concerning public health challenge. A notable phenomenon termed “Retest Positive” for SARS-CoV-2 has been observed in individuals who seemingly recovered from COVID-19, leading to difficulties in distinguishing true recurrence from intermittent viral shedding.
Observations: Studies indicate that over 10% of clinically recovered COVID-19 patients exhibit re-positive RT-PCR results during post-discharge follow-up, with proportions ranging widely from 2.4% to 69.2%. While most re-positive patients are asymptomatic or have mild symptoms, some experience critical progression. A key concern is that many re-positive patients tested negative for SARS-CoV-2 IgG and IgM antibodies at the time of their positive PCR re-test.
Discussion: Several factors contribute to re-positive tests, including false RT-PCR results (due to test kit sensitivity, sample source, or procedure), intermittent viral shedding, genuine viral reactivation, or re-infection with a different SARS-CoV-2 strain. The persistence of viral RNA in stool samples for longer periods than in nasopharyngeal swabs suggests the utility of alternative sampling methods. Distinguishing between reactivation and re-infection necessitates genetic characterization of the viruses. Host immunity, immunosuppression, and environmental factors like aerosol transmission and contaminated surfaces also play roles. Recommendations include reinforcing good ventilation, strict disinfection, and hand hygiene to mitigate transmission, along with emphasizing toilet sanitation due to potential faecal-oral routes.
Conclusion: The recurrence of COVID-19 infection is a frequent occurrence. Further focused research is essential to effectively manage these patients and mitigate the future impact of the pandemic.