Demographic, clinical, and epidemiologic characteristics of persons under investigation for Coronavirus Disease 2019-United States, January 17-February 29, 2020

Abstract

Background: The Coronavirus Disease 2019 (COVID-19) pandemic, caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), evolved rapidly in the United States. This report describes the demographic, clinical, and epidemiologic characteristics of 544 U.S. persons under investigation (PUI) for COVID-19 with complete SARS-CoV-2 testing in the beginning stages of the pandemic from January 17 through February 29, 2020.

Methods: In this surveillance cohort, the U.S. Centers for Disease Control and Prevention (CDC) provided consultation to public health and healthcare professionals to identify PUI for SARS-CoV-2 testing by quantitative real-time reverse-transcription PCR. Demographic, clinical, and epidemiologic characteristics of PUI were reported by public health and healthcare professionals during consultation with on-call CDC clinicians and subsequent submission of a CDC PUI Report Form. Characteristics of laboratory-negative and laboratory-positive persons were summarized as proportions for the period of January 17-February 29, and characteristics of all PUI were compared before and after February 12 using prevalence ratios.

Results: A total of 36 PUI tested positive for SARS-CoV-2 and were classified as confirmed cases. Confirmed cases and PUI testing negative for SARS-CoV-2 had similar demographic, clinical, and epidemiologic characteristics. Consistent with changes in PUI evaluation criteria, 88% (13/15) of confirmed cases detected before February 12, 2020, reported travel from China. After February 12, 57% (12/21) of confirmed cases reported no known travel- or contact-related exposures.

Conclusions: These findings can inform preparedness for future pandemics, including capacity for rapid expansion of novel diagnostic tests to accommodate broad surveillance strategies to assess community transmission, including potential contributions from asymptomatic and presymptomatic infections.

Fig 1. Epidemiologic curve of persons under investigation for COVID-19: Frequency by determination date, SARS-CoV-2 test status, and COVID-19 case type, United States, January 17–February 29, 2020 (N = 711).

1: CDC activates the Emergency Operations Center. 2: WHO declares COVID-19 outbreak a public health emergency of international concern, and persons under investigation (PUI) evaluation criteria change to expand the travel-related epidemiologic exposure criterion (Table 1). 3: The United States introduces travel restrictions for foreign nationals with travel from China in the last 14 days. 4: PUI evaluation criteria changed to include a criterion for testing of persons with severe unexplained respiratory illness by addition of a footnote. 5: PUI evaluation criteria changed to expand the travel-related exposure criterion to include any geographic area affected by COVID-19, and the criterion for patients with severe unexplained respiratory illness, regardless of epidemiologic exposures, was moved into the main body of the PUI evaluation criteria. “Missing” = testing was performed locally and a result was not communicated to CDC, or inconsistent or missing information in linking variables did not allow for matching between CDC laboratory and epidemiologic databases. Community spread cases had no known travel- or contact-related exposures.