What you need to know about covid boosters and the latest research

New studies are fueling debate about whether the booster shot targeting the BA.4 and BA.5 versions of omicron is superior to another shot of the original. (Hannah Beier/Reuters)

Each time a new coronavirus variant looms, scientists across the world race to perform laboratory tests to understand how a key line of human immunity will hold up.

These experiments can’t answer the questions most ordinary people have: How well will my booster protect me? But they provide essential clues to guide vaccine strategy.

A handful of small studies are out on the bivalent booster shots that were rolled out in September and are designed to better match the current phase of the pandemic by incorporating components from the original version of the virus and from the BA.4 and BA.5 omicron subvariants.

The new studies show a similar picture, though there are variations in how the experiments were conducted and even bigger differences in how scientists interpret them. The studies suggest, overall, that the short-term immune responses are similar whether from a new or old booster. Both shots boost immunity, with the bivalent shots having a bit of an advantage, depending on which data you review — but they aren’t transformative.

Getting boosted today is a good idea to top off immunity. With a swarm of immune-evading subvariants looming on the horizon, the available boosters remain the best tool to help fortify protection, particularly against severe illness and death. But it’s looking ever more likely that the immune-evading variants that are gaining a foothold will cause a wave of infections this winter, even in people who have been boosted.

Coronavirus: What you need to know

Vaccines: The CDC recommends that everyone age 5 and older get an updated covid booster shot. New federal data shows adults who received the updated shots cut their risk of being hospitalized with covid-19 by 50 percent. Here’s guidance on when you should get the omicron booster and how vaccine efficacy could be affected by your prior infections.

New covid variant: The XBB.1.5 variant is a highly transmissible descendant of omicron that is now estimated to cause about half of new infections in the country. We answered some frequently asked questions about the bivalent booster shots.

Guidance: CDC guidelines have been confusing — if you get covid, here’s how to tell when you’re no longer contagious. We’ve also created a guide to help you decide when to keep wearing face coverings.

Where do things stand? See the latest coronavirus numbers in the U.S. and across the world. In the U.S., pandemic trends have shifted and now White people are more likely to die from covid than Black people. Nearly nine out of 10 covid deaths are people over the age 65.

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