Real-world assessment of reinfection with SARS-CoV-2: Implications for vaccines

There have been over 670 million confirmed cases of SARS-CoV-2 infection globally, resulting in over 6.87 million deaths. With approximately 0.1 %-6.8 % experiencing reinfection. This retrospective cohort study aimed to compare the risk of short-term circulatory and respiratory sequelae between SARS-CoV-2 reinfection and initial infection, and assess the impact of vaccination.

Data from the TriNetX US Collaborative network (2020-2022) were used to create two cohorts based on reinfection status. The main outcome assessed were medical utilization, circulatory and respiratory symptoms, and circulatory and respiratory diseases. The Kaplan-Meier method was used to compare the risks between two cohorts. Four subgroup analyses (vaccination status, age, sex, race) and six sensitivity analyses (rigorous definition, modified exclusion criteria, treatment, different COVID-19 variants timeline, address survivorship bias, and E-value calculation) were also conducted.

The reinfection cohort showed a significant reduction in medical utilization [ Hazard ratio, HR: 0.867, (95 % confidence interval, CI:0.839-0.896) for hospitalization, 0.488 (0.418-0.570) for critical care services, and 0.476 (0.360-0.629) for mechanical ventilation], lower risk of circulatory diseases [ HR: 0.701 (95 % CI:0.637-0.772), 0.695 (0.583-0.829), 0.660 (0.605-0.719), 0.741 (0.644-0.854), 0.614 (0.535-0.705), and 0.758 (0.656-0.876) for ischemic heart disease, inflammatory heart disease, dysrhythmias, venous thromboembolism, other cardiac disorders, and cerebrovascular diseases, respectively], and lower risk of respiratory diseases such as pneumonia, other acute lower respiratory infections, asthma, and hypoxemia [HR: 0.302 (95 % CI: 0.273-0.333), 0.811 (0.686-0.958), 0.791 (0.735-0.850), and 0.392 (0.338-0.455), respectively]. The vaccinated reinfection cohort showed no significant differences in medical utilization, circulatory diseases, or respiratory conditions but had a higher risk of breathing abnormalities. breathing abnormalities [HR: 1.195 (95 % CI:1.087-1.313)].

The individuals who experienced reinfection exhibited milder short-term sequelae in the circulatory and respiratory systems. Vaccine administration protects against cardiovascular or respiratory systems.