An analysis today by the Centers for Disease Control and Prevention (CDC) of COVID-19 case investigation and contact tracing data from 56 US health departments shows that heavy investigator caseloads and an unengaged public may hinder the ability to locate and quarantine contacts in a timely manner.

The study, published in Morbidity and Mortality Weekly Report, used health department reports from Jun 25 to Jul 24, 2020, to determine the effectiveness of case investigation and contact tracing in mitigating the transmission of SARS-CoV-2, the virus that causes COVID-19, through rapid identification, testing, and quarantine of contacts.

Sixty-two of 64 health departments funded by the Epidemiology and Laboratory Capacity for Prevention and Control of Emerging Infectious Diseases Cooperative Agreement submitted data on average caseload per investigator, case investigation timeliness, and contact tracing timeliness and yield. Four health departments reported no COVID-19 cases, and two were excluded after submitting only partial data.

Among the 56 remaining health departments, researchers found wide variation in capacity and ability to conduct rapid, effective contact tracing and uncovered an inverse relationship between investigator caseload and timely interviewing of patients and number of contacts per case.

Patients name few contacts

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Read more at CIDRAP…