CDC Broadens 'Person Under Investigation' Definition for COVID-19

Kari Oakes

February 28, 2020

In a telebriefing on the COVID-19 outbreak, Nancy Messonnier, MD, director of the National Center for Immunization and Respiratory Diseases at the Centers for Disease Control and Prevention announced that the agency has updated the definition of “Person Under Investigation,” or PUI, for the disease.

The definition has been revised “to meet the needs of this rapidly evolving situation,” she said. The new PUI definition includes travel to more geographic areas to reflect this past week’s marked uptick in coronavirus activity in Italy and Iran. In addition to these countries and China, recent travel to Japan or South Korea also constitutes an epidemiologic risk factor which, in conjunction with clinical features, warrant an individual being classified as a PUI. These five countries each now have widespread person-to-person transmission of the virus.

Dr. Messonnier left open the possibility that the PUI definition would continue to evolve if such transmission within communities becomes more common. Asked whether the small number of U.S. cases thus might be an artifact of low test volumes, she said, “We aggressively controlled our borders to slow the spread. This was an intentional U.S. strategy. The CDC has always had the capacity to test rapidly from the time the sequence was available. ...We have been testing aggressively.”

The original PUI definition, she explained, emphasized individuals with fever, cough, or trouble breathing who had traveled recently from areas with COVID-19 activity, in particular China’s Hubei province. “We have been most focused on symptomatic people who are closely linked to, or who had, travel history, but our criteria also allow for clinical discretion,” she said. “There is no substitute for an astute clinician on the front lines of patient care.”

The first COVID-19 case from person-to-person spread was reported on Feb. 27. “At this time, we don’t know how or where this person became infected,” said Dr. Messonnier, although investigations are still underway. She responded to a question about whether the CDC delayed allowing COVID-19 testing for the patient for several days, as was reported in some media accounts.

“According to CDC records, the first call we got was Feb. 23,” when public health officials in California reported a severely ill person with no travel abroad and no known contacts with individuals that would trigger suspicions for coronavirus. The CDC recommended COVID-19 testing on that day, she said.

Dr. Messonnier declined to answer questions about a whistleblower report alleging improper training and inadequate protective measures for Department of Health & Human Services workers at the quarantine center at Travis Air Force Base, Calif.

As local tests become available, the most updated information will be coming from state and local public health departments, she stressed, adding that the CDC would continue to update case counts on Monday, Wednesday, and Friday of each week. Procedures are being developed for the management of patients presumed to have COVID-19, where local health departments see positive tests but the mandatory CDC confirmatory test hasn’t been completed.

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