Dr. Rattay

The state will soon rely on new data calculations to determine how COVID-19 is spreading throughout the community, Delaware public health officials announced Tuesday. 

Delaware's novel coronavirus COVID-19 pandemic dashboard will now include the percent positive for total tests in addition to the number of individuals tested. 

"Since the beginning of this epidemic we've been providing percent positives based on people tested, as opposed to the total tests that are done," Division of Public Health Director Karyl Rattay said Tuesday. "Many states have been presenting their results in that way--people tested as opposed to total tests--there's value and benefit in presenting the information both ways and so we're excited to be able to provide the data both ways."

The new algorithm is the recommended presentation of data used by the CDC and Johns Hopkins, and it's particularly important based on how comparisons are made against other states, she said. 

Delaware's percent positive appears higher than other states because of the current reporting method, but a total test percent positive report will provide data that more closely matched neighboring state's reported data. 

"The test rate results reporting reflects the percentage of the tested population who is infected, but it also is a reflection of how well are we doing with testing. So the better we're doing with testing, the more people that we get tested, you would expect that number to go lower," Rattay said. "The person based test, really, it was very equivalent in the beginning--in fact, even pretty equivalent in the summer--but now that more and more people are are being tested and people are getting repeat tests, that calculation is better to assess kind of your overall prevalence, or burden of infection."

This is because more tests have been conducted than the number of persons who have been tested due to repeat testing. So one displays a higher number of COVID-19 positivity than the other. 

"Each has value, but you will see that number going down once once we switch over to the test based approach," Rattay said. 

The change in reporting comes as Delaware sees upticks across the board regarding community spread, with outbreaks of particular concern in a handful of long-term care facilities, including three previously reported sites and a fourth location in Hockessin, the Regal Heights Health Care and Rehabilitation Center. 

Tuesday's data, provided by officials, suggested a more than 8% positivity percentage, the highest in months. Governor John Carney said positive tests from long-term care facilities and the University of Delaware are impacting the overall status of the state.

"The combination of those numbers is concerning and it's not headed in the right direction," he said. "Is it to the point where we want to tighten things down like we did last time, with zip codes along the beach communities? Not to that extent. We will continue to look at it on a day-to-day basis, week-to-week basis... but my message to every Delawarean is, if we don't want to go backwards, let's follow the guidelines, let's wear face masks in particular. And let's be careful in public settings, particularly indoors--at the stores, at the various indoor locations such as supermarkets, and all those places that we go--wear your mask, be respectful of others."