With two years of the COVID-19 pandemic behind us, medical experts continue to learn more about the disease, including best practices for prevention and treatment. Although research remains ongoing, it is clear that the COVID-19 vaccine is the best tool for preventing infection as well as severe illness, hospitalization or death. As the virus continues to evolve, however, many individuals who have been vaccinated are now testing positive for COVID-19. Both vaccination and an infection provide antibodies, which begs the question, should a vaccinated individual who tests positive still get a booster shot of the vaccine?
According to Dr. Michael Chang, Assistant Professor of Pediatrics and Director of Pediatric Antimicrobial Stewardship for McGovern Medical School at UTHealth Houston andChildren’s Memorial Hermann Hospital, the answer is a resounding yes.
“Immunity against illness and severe illness from COVID-19 appears even better when the immunity is derived from a combination of vaccination and infection,” Chang explained. “So far, the data we have suggests that being vaccinated prior to infection, and then getting infected, generates a broader and longer lasting immunity than vaccination and infection alone—something experts are calling hybrid immunity.”
Chang added that when scientists compare immunity from vaccination with immunity from an infection only, the vaccination provides a more predictable level of immunity. In addition, antibodies from a vaccination also appear to last longer than those from an infection alone, although hybrid immunity seems to offer the longest duration of antibodies. He noted that it was also important to remember that the Delta and Omicron variants, as well as the Omicron subvariants, evolved to a point that they are able to “escape” immunity from prior COVID-19 infections as well as some vaccinations.
“If you had an infection early on in the pandemic, we suspect that your protection against severe disease from the Omicron variant has likely decreased significantly,” Chang said. “Medical experts highly recommend an additional dose of the COVID-19 vaccine for anyone who was previously infected, which should increase protection against severe disease from Omicron.”
Chang acknowledged that for individuals who have been vaccinated and then test positive for COVID-19, the infection likely increases immunity in a similar manner as a booster shot. However, he would by no means encourage anyone to purposefully expose themselves to COVID-19 in an effort to gain those natural antibodies. He added that the Centers for Disease Control and Prevention (CDC) also does not consider a COVID-19 infection an equivalent to a vaccination, including a booster, which may be important for any future documentation requiring vaccination status. Even more, for patients who may be suffering from post-acute COVID-19 syndrome, colloquially known as “long COVID,” these symptoms may decrease following a COVID-19 vaccination or booster shot.
For individuals looking to get their booster after a COVID-19 infection, Chang said that as long as you are finished with the recommended isolation time period, it is safe to get the COVID-19 vaccine. The same rule applies for a booster shot or the primary series of the vaccine for anyone who may not yet be vaccinated with a first or second dose. He added that individuals do not need to get the same “brand” of vaccine for their booster as they did for their primary series, and that “mixing and matching” the vaccine brand may be helpful, but more research is needed to make a recommendation on that practice.
“Antibody levels after infection or vaccination tend to increase for the first 6 to 12 weeks and then start falling after that, although the time period is different for everyone,” Chang explained. “Some new data is now suggesting that some antibodies from infection or vaccination may last as long as 1.5 years, so if you were recently infected, it would be reasonable to wait approximately 3 to 5 months to get a booster shot, since your antibodies were likely boosted from the infection. The important thing is to get the booster shot eventually, as it will only offer added protection.”
Chang noted that there is no evidence that getting a booster soon after a COVID-19 infection increases the risk of any side effects or dangerous complications. He addressed the observed cases of myopericarditis (inflammation of heart tissue) in young adult males following the mRNA vaccines (Pfizer-BioNTech or Moderna), but added that it is self-limited and of short duration. In addition, data suggests that myopericarditis following a COVID-19 infection is actually higher and potentially much longer lasting than the cases observed after the COVID-19 vaccine.
“It is safe to get the booster at any time after infection, but if you feel like waiting a few months, that is fine since your natural antibodies should help protect you,” he said. “The bottom line is that getting a COVID-19 vaccine booster after infection maximizes your protection against severe infection going forward, so staying up-to-date on your vaccinations is still the safest and most effective way to minimize the impact of ongoing COVID-19 infections, especially as we transition from pandemic to endemic circulation.”