A research team at Columbia University has built a mathematical model that gives a much more complete — and scary — picture of how much virus is circulating in our communities. It estimates how many people are never counted because they never get tested. And it answers a second question that is arguably even more crucial — but that until now has not been reliably estimated: On any given day, what is the total number of people who are actively infectious? This includes those who may have been infected on previous days but are still shedding virus and capable of spreading disease. The model's conclusion: On any given day, the actual number of active cases — people who are newly infected or still infectious — is likely 10 times that day's official number of reported cases. Why The Pandemic Is 10 Times Worse Than You Think