Current information indicates that if you received the Pfizer or Moderna vaccines you will be well-protected against the delta variant. One study found an 88% efficacy against delta, a modest decrease compared to the original efficacy of 95%.
There is also excellent protection against severe disease that would require hospitalization. The most current data for Johnson and Johnson indicates that it isn’t as effective.
A new, and unpublished, study from researchers at New York University looked at the neutralizing antibody response against the delta variant in people who received the Johnson and Johnson vaccine. Neutralizing antibodies are the type that are most effective at stopping the infection. They found the Johnson and Johnson vaccine was less effective at producing antibodies against the delta variant and believe it could result in decreased protection.
The result is based on a blood test that only measures one part of a person’s immune response. The immune system can protect us in ways that don’t rely on the antibodies being measured and it’s possible that studies of actual infection rates in people might find a better level of protection or continued protection against severe disease.
It’s also important to note that prior research released by Johnson and Johnson found that the vaccine did product significant neutralizing antibodies to the delta variant and that they further increased over time.
People who received the Johnson and Johnson vaccine want to know how well they are protected. There is currently conflicting data on the answer to that questions. Authors of the latest study suggested that people receive a booster shot of either the Johnson and Johnson vaccine again or a dose of Pfizer or Moderna.
There is currently no official recommendation for a booster shot.