PriMera Scientific Medicine and Public Health (ISSN: 2833-5627)

Research Article

Volume 7 Issue 2

Covid-19 Relapse in the Post-Pandemic World: Mechanisms, Diagnosis, And Management Strategies

Taroob Runa T*

August 01, 2025

Abstract

Background: COVID-19 relapse, or "rebound," has emerged as a recognized phenomenon during the post-pandemic period, particularly in patients receiving antiviral therapies such as nirmatrelvir/ritonavir (Paxlovid). While often clinically mild, such rebounds raise concerns regarding viral transmission, patient management, and long-term therapeutic strategies.

Objective: This review aims to provide a comprehensive overview of the mechanisms, diagnosis, risk factors, and management strategies associated with post-treatment COVID-19 relapse.

Methods: A narrative review was conducted using recent clinical studies, epidemiological data, and mechanistic models published between 2022 and 2025. Particular emphasis was placed on immune response dynamics, treatment timing, and population-specific vulnerabilities.

Results: COVID-19 relapse is most commonly observed 2-8 days after completing antiviral therapy, with preserved target cells and incomplete viral clearance identified as key contributing factors. Early initiation of antiviral therapy, immunosuppression, high comorbidity burden, and steroid use have all been associated with increased relapse risk. While rebound is not exclusive to any single antiviral agent, current evidence suggests that extending treatment duration or tailoring regimens to high-risk populations may reduce recurrence. Most rebound cases remain typically mild and transient, but proper diagnosis and isolation remain essential to limit transmission.

Conclusion: Understanding COVID-19 relapse is crucial for improving patient outcomes and guiding future antiviral strategies.

Further research needed: Optimize treatment timing Strengthen immune response monitoring, and Prevent relapse in vulnerable populations.

Keywords: COVID-19 relapse; Viral rebound; Paxlovid (nirmatrelvir/ritonavir); SARS-CoV-2; Antiviral therapy; Immune response dynamics; Reinfection vs. relapse; Post-treatment rebound; COVID-19 rebound risk factors

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