- JAMA op-ed authors discuss the early limited evidence of postinfection immunity after COVID-19 recovery and highlight current knowledge gaps.
Why this matters
- If COVID-19 recovery affects immunity to or severity of reinfection, those factors could play into public health decisions about social distancing.
- Someone with immunity also might be able to donate convalescent plasma.
- What is known:
- After infection with SARS-CoV-2, IgM and IgG antibodies are detectable within days to weeks of symptom onset in most individuals.
- With most other coronaviruses, concentrations of IgG remain high for about 4-5 months and then decline gradually over the next 2-3 years.
- A study of 9 patients with COVID-19 found higher antibody titers with greater clinical severity.
- A study of 4 rhesus macaques deliberately infected with SARS-CoV-2 found that the animals did not become reinfected 28 days later when they were rechallenged with the virus.
- Gaps in knowledge:
- The durability and duration of neutralizing antibodies against SARS-CoV-2 is unknown.
- The relationship between antibody response and clinical improvement is unclear.
- Whether higher antibody titers correlate with clinical improvement is unknown.
- How long virus shedding persists is not known.