New coronavirus cases continued their sharp decline over the past week — progress that could help the U.S. find its way out of the pandemic faster and more safely, if it keeps up.

The big picture: Getting the virus' spread under control is the key to saving lives and reopening schools and businesses. And the tools to achieve that — masks, social distancing and vaccines — are also the most effective weapons against the more contagious variants that could threaten the U.S.' progress.

By the numbers: An average of 108,000 Americans were diagnosed with COVID-19 infections each day over the past week.

• That’s a 24% decline from the week before.
• Hospitalizations were also down last week, by about 8%, and deaths fell by 3%. The virus is still killing an average of roughly 3,000 Americans per day.

Between the lines: 108,000 new cases and 3,000 deaths per day is still a very bad situation, and shouldn't be considered a sustainable level of infection.

• But after the horrific winter outbreak the U.S. experienced, the only way to have a small number of cases is to keep climbing down week after week. And that’s happening.
• Nationwide, average daily cases have been declining by double digits for four weeks straight. Cumulatively, they've fallen by roughly 55% over that time.
• It’s been three weeks since even a single state reported an increase in average daily infections.

This is real progress.

What’s next: Experts have warned that new, more contagious variants of COVID-19 are gaining ground in the U.S. and likely will soon become the dominant strain here. That means each infected person is more likely to spread the virus.

• The best ways to avoid a surge in cases from those variants is to ramp up vaccinations, buckle down on masks and social distancing — including double masks when necessary — and continue to reduce the number of infected people.

Each week, Axios tracks the change in new infections in each state. We use a seven-day average to minimize the effects of day-to-day discrepancies in states’ reporting.