Temperature and symptom-based screening programs don't help catch coronavirus cases, the CDC said in a new report that took a closer look at the programs used at US airports until mid-September … Between January 17 and September 13, the CDC screened more than 766,000 travelers. Nearly 300 met the criteria for public health assessment, 35 were tested for the coronavirus, and nine tested positive. That means the program identified about one case per 85,000 travelers screened, the CDC reported Thursday in the agency's weekly report.