From the Guidelines
Repeat COVID infections are a significant concern, with approximately 11-15% of individuals experiencing reinfection, and the risk increasing over time since the last infection or vaccination, typically after 3-6 months. The severity of subsequent infections may decrease for some individuals, but repeated infections can still lead to cumulative damage, particularly affecting the cardiovascular, respiratory, and neurological systems 1. The risk of developing long COVID remains with each infection, estimated at 5-30% depending on vaccination status and other factors 1.
Key Statistics
- 11-15% of people who have had COVID-19 will experience at least one reinfection
- Risk of reinfection increases with time since the last infection or vaccination, typically after 3-6 months
- 5-30% risk of developing long COVID with each infection, depending on vaccination status and other factors
Reducing Reinfection Risk
To minimize the risk of reinfection, staying up-to-date with COVID vaccinations is crucial, with the latest formulations targeting current variants. Additional protective measures include:
- Wearing high-quality masks in crowded indoor settings
- Maintaining good ventilation
- Practicing hand hygiene People with compromised immune systems or underlying health conditions should take extra precautions as they face higher risks from repeat infections 1.
Clinical Implications
The impact of COVID-19 on respiratory muscle performance is a significant concern, with 38% of nonhospitalized patients developing dyspnea, and 43% of hospitalized patients still experiencing dyspnea at 2 months post-hospitalization 1. Screening for respiratory muscle weakness and providing interventions to improve respiratory muscle performance appears to be essential for patients with COVID-19.
From the Research
COVID-19 Reinfection Statistics
- The protection offered from prior COVID-19 infection was 81.8% (95% confidence interval [CI], 76.6-85.8) against reinfection and 84.5% (95% CI, 77.9-89.1) against symptomatic infection 2.
- A retrospective cohort study found that of 1278 patients who tested positive for COVID-19 and were retested after 90 days, 62 had possible reinfection, with 31 (50%) being symptomatic 2.
- The study also found that prior infection in patients with COVID-19 was highly protective against reinfection and symptomatic disease, with this protection increasing over time 2.
- Another study found that early administration of combination therapy with a direct antiviral and sotrovimab seems to be effective in preventing hospitalization, progression to severe COVID-19, and development of prolonged/persisting SARS-CoV-2 infection in immunocompromised patients 3.
- However, the study also found that the efficacy of this strategy may decrease with the evolution of SARS-CoV-2 variants 3.
Factors Associated with Reinfection
- A study found that factors associated with longer infection were initiation of therapy 3 days after symptom onset and enrollment for more than 180 days from the beginning of the study 3.
- However, only the latter factor was independently associated with a longer SARS-CoV-2 infection, suggesting a loss of efficacy of the treatment strategy with the evolution of SARS-CoV-2 variants 3.
Treatment and Prevention
- A study found that nirmatrelvir/ritonavir plus standard of care may reduce all-cause mortality and hospital admission or death in unvaccinated, high-risk patients with mild symptomatic COVID-19 4.
- The study also found that nirmatrelvir/ritonavir plus standard of care probably has little or no effect on treatment-emergent adverse events, but probably increases treatment-related adverse events such as dysgeusia and diarrhea 4.