Expect more worrisome Covid-19 variants after Omicron: scientists
- Experts say there’s no guarantee future variants will cause milder illness or that existing vaccines will work against them
- With both Omicron and Delta circulating, people may get double infections that could spawn ‘Frankenvariants’ hybrids

Scientists warn that Omicron’s whirlwind advance practically ensures it will not be the last version of the coronavirus to worry the world.
Every infection provides a chance for the virus to mutate, and Omicron has an edge over its predecessors: It spreads much faster despite emerging on a planet with a stronger patchwork of immunity from vaccines and prior illness.
That means more people in whom the virus can further evolve. Experts do not know what the next variants will look like or how they might shape the pandemic, but they say there’s no guarantee the sequels of Omicron will cause milder illness or that existing vaccines will work against them.
They urge wider vaccination now, while today’s shots still work.
“The faster Omicron spreads, the more opportunities there are for mutation, potentially leading to more variants,” Leonardo Martinez, an infectious disease epidemiologist at Boston University, said.