When you go out into public these days, you may come across someone who has COVID-19 — but how likely is it? An interactive map is trying to answer that question.

What You Need To Know

  • COVID-19 Event Risk Assessment Planning Tool shows COVID-19 risk in group settings
  • You can see breakdown by county across the country
  • The chief of UB's Division of Infectious Diseases says the tool is useful but warns it shouldn't guide your behavior

Dr. Thomas Russo, the chief of the University at Buffalo's Division of Infectious Diseases, said, "I think this tool is interesting." 

The COVID-19 Event Risk Assessment Planning Tool was created as part of a project led by professors at the Georgia Institute of Technology. The resource shows how likely it is that at least one person at any event of a given size is infected with COVID-19.

"If you look at Erie County right now with the number of cases we have and it does have a lag of a number of days, if there's a gathering of 10 individuals, the likelihood that someone that's infectious that would be present at that gathering would be somewhere between 23 and 40 percent based on this tool," Dr. Russo said.

The interactive map allows you to click on different counties across the country and see the risk level based on group sizes of 10 up to 5,000.

But there is concern about underreporting due to testing shortages, asymptomatic cases, and reporting lags. For this tool, researchers are applying an ascertainment bias of 5 and 10 to account for undiagnosed cases. Dr. Russo thinks that method brings about a more accurate picture of the pandemic.

He said, "We've been averaging about 500 new diagnosed cases in our community each day over the last several days, well the reality is probably it's somewhere in between 5 and 10-fold greater than the number of diagnosed cases which obviously puts us in the thousands."

Dr. Russo believes the map is a useful guide to get a sense of the virus' prevalence in certain areas but warns the tool shouldn't guide your behavior. 

"Population statistics don't apply to you and your individual event so even though you may feel the odds in your favor, it just really takes one individual that happens to be infected that was statistically unlikely to be in your house but if they are there that's going to be problematic," he said.

He reminds people the virus is widespread in the area and urges people against gathering outside their household over the holidays.