Some vaccines are being updated in case health authorities decide a change is needed.
Pfizer is enrolling healthy adults to test a reformulated COVID-19 vaccine that matches the hugely contagious omicron variant, to see how it compares with the original shots. Pfizer and its partner BioNTech announced the study on Tuesday. COVID-19 vaccine-makers have been updating their shots to better match omicron in case global health authorities decide the change is needed. Omicron is more likely than previous variants to cause infection even in people who’ve been vaccinated, but it’s not yet clear that a change to the vaccine recipe will be ordered. Among the issues regulators are weighing: Some of the first places to face an omicron surge already are seeing the mutant wane – and there’s no way to know if the next variant that arises will resemble omicron or be totally different. The original vaccines still offer good protection against severe illness and death. Studies in the U.S. and elsewhere have made clear that adding a booster dose strengthens that protection and improves the chances of avoiding even a milder infection. Another wrinkle in deciding whether vaccines need an update: A new U.
