COVID-19 Contact Tracing Had Little Impact on Population Health

June 08, 2021 - Contact tracing was largely ineffective in slowing COVID-19 virus transmission and improving population health, mostly due to insufficient interview responses, according to a recent study published in JAMA Network Open.

In an analysis of over 74,000 cases between June and October of 2020 from 13 health departments and one Indian Health Service Unit, researchers found that two of three people with COVID-19 were not reached for an interview or did not name any contacts when interviewed. Public health authorities reached a mean 0.7 contacts by telephone, and only 0.5 contacts per case were adequately monitored.

“In this cross-sectional study of US local COVID-19 surveillance data, testing named contacts was a high-yield activity for case finding,” the study stated. Despite this, the lack of interviewing and naming contacts made the process of contact tracing largely ineffective in improving population health.

“These findings are relevant to decisions regarding the allocation of public health resources among the various prevention strategies and for the prioritization of case investigations and contact tracing efforts,” the study continued.

Contact tracing challenges include a lack of response to calls from public health officials, a reluctance to share contact names for fear of subjecting others to quarantine, and mistrust of government. Researchers assessed each health department’s actual total number of obtained contacts compared to a hypothetical estimated number given that all individuals had been reached for an interview and named contacts. There was a four-week assessment period for the analyzed cases.

Of confirmed COVID-19 cases in the cohort, 59 percent participated in interviews while 33 percent named contacts. However, 44 percent did not name any contacts. Health departments with the highest case counts conducted significantly fewer interviews than those with low case counts.

Researchers estimated that over 200,000 additional contacts could have been named from the over 74,000 initial cases. Despite this estimate, only 74,839 additional contacts were actually named. An estimated 66 percent of contacts were missed during the process, researchers concluded.

“Timely collection and communication of relevant information are essential for performing contact tracing,” the study explained. All the observed health departments faced significant roadblocks to effective contact tracing.

“These challenges included missing and incomplete data, paper-based records, disparate digital databases without common identifiers, and insufficient personnel to maintain, improve, or implement new systems.”

Researchers concluded that additional targeted outreach campaigns could have a positive impact on improving contact tracing results. Communities must have trust in public health officials and the effectiveness of contact tracing for it to be effective. In addition, health departments must have the proper resources to keep up with contact tracing for a high volume of cases.

While contact tracing in this instance did not have a significant impact on population health, the healthcare industry has been researching and investing in other innovative methods of slowing the spread of COVID-19.

A recent opinion piece published in JAMA Network explored the use of precision medicine in treating and reducing negative health outcomes of COVID-19. Despite its promise, researchers found that like contact tracing, precision medicine’s use for COVID-19 treatment depends on successful logistical efforts to streamline the process, including standardized taxonomy and subtypes.

While the entire healthcare industry is working on innovative ways to treat and control COVID-19, the sheer volume of cases and other external barriers are proving to be difficult to overcome.