The US has reported more than 30 million cases of coronavirus since the start of the pandemic, even as the number of new infections has suddenly slowed after a surge in the fall and early winter.
According to data from Johns Hopkins University, the nation passed the milestone on Wednesday, nearly 12 weeks after reaching 20m. It had taken the US less than two months to go from 10 million to 20 million cases.
Brazil has recorded the second highest cumulative total with 12.1 million cases, followed by 11.7 million cases in India, where daily infections have increased in recent weeks.
In the US, new cases and hospital admissions related to Covid-19 have fallen this year, while vaccinations have increased by 46.3 million fully vaccinated Americans.
According to JHU, the US has counted about 48,000 new cases per day in the past week, below a peak of 250,000 in early January. Data also showed that as of March 12, 37,231 people with Covid-19 were in the hospital, compared to a maximum of 128,312 at the start of the year.
The delay comes as more Americans are vaccinated against Covid-19. According to the Centers for Disease Control and Prevention, the US has administered more than 130 million doses.
Data published on Wednesday also found that 85.4 million people have received at least one injection so far, equal to a quarter of the total population. One-third of the adult population and 70 percent of seniors have received one or more doses since the introduction of the vaccine in December.
The number of U.S. deaths attributed to Covid-19 totaled 544,922, JHU said. New fatalities followed other statistics on a down trajectory, reaching the daily level last seen in November, according to the CDC.