A virus that shows no signs of disappearing, variants that are adept at dodging the body’s defenses and waves of infections two, maybe three times a year — this may be the future of COVID-19, some scientists now fear.

The central problem is that the coronavirus has become more adept at reinfecting people. Already, those infected with the first omicron variant are reporting second infections with the newer versions of the variant — BA.2 or BA2.12.1 in the United States, or BA.4 and BA.5 in South Africa.

Those people may go on to have third or fourth infections, even within this year, researchers said in interviews. And some small fraction may have symptoms that persist for months or years, a condition known as long COVID.