The Department of Homeland Security's (DHS) science and technology directorate has created a tool that works to predict the environmental persistence of SARS-CoV-2, which causes COVID-19, at varying temperature and relative humidity levels.
DHS said Wednesday that the predictive modeling application is built upon research efforts at the National Biodefense Analysis and Countermeasures Center and designed to support coronavirus response efforts.
S&T researchers found that SARS-CoV-2 virus can stay viable in saliva droplets that have landed on surfaces over long periods of time and used their findings to develop the virus decay calculator that generate estimates under various representative indoor environments.
The initial predictive model can analyze infectivity in virus at a humidity range of 20 percent to 60 percent and a room temperature range of 70 to 95 degrees Fahrenheit, according to the department. S&T intends to regularly update the model as the directorate continues to yield additional virus stability data.
"Transmission occurs primarily through respiratory droplets produced by talking, coughing and sneezing," said William Bryan, acting undersecretary for science and technology at DHS. "If these droplets settle on surfaces or objects, contact with those contaminated surfaces may also be a factor in spreading the virus," Bryan added.