For the second year in a row, the global pandemic has dominated our blog — and our readers' attention. Our top COVID stories reveal the ever-changing nature of the crisis. In February,

readers were curious about India's mysterious drop in cases, which spiked again — creating another popular story — in spring. In summer, people wanted to read about the delta variant,

only to shift focus to omicron in winter. All the while, readers wanted to know: were vaccines and masks still effective against all the coronavirus mutations? This list of stories, says NPR

correspondent Michaeleen Doucleff, "really shows how so much has happened in just a year." "Last December, we were still doubtful the variants would change the course of the

HERE'S WHY What happened? Here are six lessons learned from Israel's experience — and one looming question for the future of the pandemic. _Published August 20, 2021_ HOW

SARS-COV-2 IN AMERICAN DEER COULD ALTER THE COURSE OF THE GLOBAL PANDEMIC Scientists have evidence that SARS-CoV-2 is circulating in white-tailed deer in the U.S. They say the findings could

essentially dash any hopes of eliminating the virus in the U.S. — and the world. _Published Nov. 10, 2021_ EXTRAORDINARY PATIENT OFFERS SURPRISING CLUES TO ORIGINS OF CORONAVIRUS VARIANTS

Scientists looked at a possible link between mutations in the U.K. and South Africa — and those in a patient in Boston who had living, growing virus in his body for five months. _Published

Feb. 5, 2021 _ HOW INDIA WENT FROM A RAY OF HOPE TO A WORLD RECORD FOR MOST COVID CASES IN A DAY India's COVID-19 caseload plummeted to record lows in February. Now a startling spike is

causing health systems — and possibly law and order — to break down. What went wrong? _Published April 22, 2021 _ NEW STUDIES FIND EVIDENCE OF 'SUPERHUMAN' IMMUNITY TO COVID-19 IN

SOME INDIVIDUALS That's how some scientists describe the findings of a series of studies looking at the antibodies created by individuals who were infected by the coronavirus and then

had an mRNA vaccine. _Published Sept. 7, 2021 _ COVID'S ENDGAME: SCIENTISTS HAVE A CLUE ABOUT WHERE SARS-COV-2 IS HEADED Pandemic predictions have been made — and then things would

change. But based on models and studies (including a 1980s test that squirted virus up human noses), researchers have a new endgame thesis. _Published Oct. 29, 2021_ THE DELTA VARIANT

ISN'T JUST HYPER-CONTAGIOUS. IT ALSO GROWS MORE RAPIDLY INSIDE YOU New research from China suggests people infected with the delta variant have, on average, about 1,000 times more virus

in their respiratory tracts than those infected with the original strain. _Published July 21, 2021 _ WHAT OMICRON'S FAST SPREAD COULD MEAN FOR THE U.S. – AND THE WORLD The variant has

spread through South Africa with remarkable speed — and been detected in at least 60 other countries. Specialists are trying to figure out the next stage for this unwelcome variant.

_Published Dec. 10, 2021 _ STUDIES SUGGEST SHARP DROP IN VACCINE PROTECTION VS. OMICRON — YET CAUSE FOR OPTIMISM In small studies in South Africa and in Germany, the results indicate a

marked decrease in the ability of vaccines to neutralize this variant. But there are other findings that are encouraging. _Published Dec. 8, 2021 _ THE MYSTERY OF INDIA'S PLUMMETING

COVID-19 CASES From 100,000 cases a day in September, India was down to about 10,000 a day early this year. Is it climate? Demographics? Mask mandates? Scientists are looking for answers.

_Published Feb. 1, 2021 _ CORONAVIRUS FAQ: WHY AM I SUDDENLY HEARING SO MUCH ABOUT KF94 MASKS? There are N95s, the top of the line in terms of protection. There are KN95s, which you can buy

easily — except quality may vary. But early this year, South Korea's KF94 masks began getting a lot of buzz. _Published Jan. 22, 2021_ Copyright 2021 NPR. To see more, visit

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