STEVE INSKEEP, HOST:
We are able today to better understand the pandemic’s spread in the United States. A new calculation tells us roughly how many Americans are spreading the virus each day. It’s been common to quote a different number, the number of new infections reported every day. Some days that is a really big number. Yet, big as it is, health officials have known for months that that number is an understatement. Many people are infected but not reported. Even more people infected in the past remain infectious. Now a research team at Columbia University has come up with a way to calculate how many people are spreading.
NPR global health correspondent Nurith Aizenman has seen this. Hey there, Nurith
NURITH AIZENMAN, BYLINE: Hi, Steve.
INSKEEP: So what’s the new calculation?
AIZENMAN: OK, quick version – the true number of active cases, people who are still…