The omicron variant of Covid-19 has branched out into more transmissible and evasive versions.
After the month of May saw the United States cross the line of more than 1 million reported deaths from Covid-19, the SARS-CoV-2 virus that causes the disease is continuing to mutate. That means a growing number of new omicron subvariants are now fueling another rise in infections. The formula for containing the worst effects of the pandemic — namely vaccinations and treatments — still holds up. But progress has been slow, leaving the world vulnerable to more troubling changes to the virus.
The US is inching closer to authorizing Covid-19 vaccines for one of the last unprotected age groups, children under 5 years old. Pfizer and BioNTech reported preliminary data this week that a three-dose sequence of its Covid-19 vaccine yielded 80 percent efficacy in preventing disease in kids between six months and 5 years old. But the Food and Drug Administration will not meet until next month to consider granting emergency approval for these shots.