Average daily new coronavirus cases in the United States dipped below 100,000 in recent days for the first time in months, but experts cautioned Sunday that infections remain high and precautions to slow the pandemic must remain in place.

Coronavirus deaths and cases per day in the U.S. dropped markedly over the past couple of weeks but are still running at alarmingly high levels, and the effort to snuff out COVID-19 is becoming an ever more urgent race between the vaccine and the mutating virus.