India has now reported more than 20 million coronavirus infections, including nearly 3.5 million people who are actively being treated for COVID-19. The country's health system is in a state of collapse as hospitals and clinics face dire shortages of beds and lifesaving supplies.

In just the past week, India has seen its COVID-19 cases jump by 2,646,526 — a figure that, if it stood alone, would currently make India the 14th worst-hit nation in the world, according to data compiled by Johns Hopkins University. On April 27, the government reported 17,636,307 total cases; by Tuesday, the number had risen to 20,282,833.

As alarming as the recent figures are, experts say they are almost certainly an undercount — possibly by a whole lot.

"At this pace of infection, India is probably only detecting 3 or 4% of its cases," says Chris Murray, director of the Institute for Health Metrics and Evaluation at the University of Washington. "So we're talking about every day, maybe 5 million infections a day in India right now. That's a huge number."

Oxygen shortages are blamed for deaths at even the best-equipped urban hospitals. On Saturday, in the capital New Delhi, 12 patients died at Batra Hospital after the facility ran out of medical oxygen. A tanker delivery had arrived just 90 minutes late.

Meanwhile, at Ballia district hospital, a facility in a rural area of Uttar Pradesh in northern India, a local reporter saw more than 20 patients on the floor, struggling to breathe. "Helpless cries of pain filled the air. Not a single doctor was in attendance," she reported.

On Saturday, India expanded COVID-19 vaccine eligibility, theoretically allowing everyone over 18 to register to get the potentially lifesaving shots. But the country has nowhere near enough vaccine doses for its adult population, and the vaccination effort has slowed across India. Clinics in several states have closed completely due to a lack of supply.

As of Tuesday, nearly 159 million vaccine doses had been administered in a country whose population is nearly 1.4 billion.

Seven Indian states have each reported more than 1 million COVID-19 cases, and others are soaring toward that mark. The most confirmed cases are in Maharashtra, which has reported nearly 4.8 million cases — roughly equal to Russia's total.

At least 222,408 people have died from COVID-19 in India, according to the country's health ministry. Only Brazil and the U.S. have higher death tolls.

The U.S. continues to have the most confirmed COVID-19 cases in the world with nearly 32.5 million. More than 577,000 Americans have died from the disease.

NPR's Lauren Frayer contributed reporting from Mumbai, India.

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