Estimated COVID-19 Cases and Hospitalizations Averted by Case Investigation and Contact Tracing in the US.

Importance: Evidence of the impact of COVID-19 case investigation and contact tracing (CICT) programs is lacking, but policy makers need this evidence to assess the value of such programs. Objective: To estimate COVID-19 cases and hospitalizations averted nationwide by US states' CICT programs. Design, Setting, and Participants: This decision analytical model study used combined data from US CICT programs (eg, proportion of cases interviewed, contacts notified or monitored, and days to case and contact notification) with incidence data to model outcomes of CICT over a 60-day period (November 25, 2020, to January 23, 2021). The study estimated a range of outcomes by varying assumed compliance with isolation and quarantine recommendations. Fifty-nine state and territorial health departments that received federal funding supporting COVID-19 pandemic response activities were eligible for inclusion. Data analysis was performed from July to September 2021. Exposure: Public health case investigation and contact tracing. Main Outcomes and Measures: The primary outcomes were numbers of cases and hospitalizations averted and the percentage of cases averted among cases not prevented by vaccination and other nonpharmaceutical interventions. Results: In total, 22 states and 1 territory reported all measures necessary for the analysis. These 23 jurisdictions covered 42.5% of the US population (approximately 140 million persons), spanned all 4 US Census regions, and reported data that reflected all 59 federally funded CICT programs. This study estimated that 1.11 million cases and 27 231 hospitalizations were averted by CICT programs under a scenario where 80% of interviewed cases and monitored contacts and 30% of notified contacts fully complied with isolation and quarantine guidance, eliminating their contributions to future transmission. As many as 1.36 million cases and 33 527 hospitalizations could have been prevented if all interviewed cases and monitored contacts had entered into and fully complied with isolation and quarantine guidelines upon being interviewed or notified. Across both scenarios and all jurisdictions, CICT averted an estimated median of 21.2% (range, 1.3%-65.8%) of the cases not prevented by vaccination and other nonpharmaceutical interventions. Conclusions and Relevance: These findings suggest that CICT programs likely had a substantial role in curtailing the pandemic in most jurisdictions during the 2020 to 2021 winter peak. Differences in outcomes across jurisdictions indicate an opportunity to further improve CICT effectiveness. These estimates demonstrate the potential benefits from sustaining and improving these programs.

Strategies to Inform Allocation of Stockpiled Ventilators to Healthcare Facilities During a Pandemic.

During a severe pandemic, especially one causing respiratory illness, many people may require mechanical ventilation. Depending on the extent of the outbreak, there may be insufficient capacity to provide ventilator support to all of those in need. As part of a larger conceptual framework for determining need for and allocation of ventilators during a public health emergency, this article focuses on the strategies to assist state and local planners to allocate stockpiled ventilators to healthcare facilities during a pandemic, accounting for critical factors in facilities' ability to make use of additional ventilators. These strategies include actions both in the pre-pandemic and intra-pandemic stages. As a part of pandemic preparedness, public health officials should identify and query healthcare facilities in their jurisdiction that currently care for critically ill patients on mechanical ventilation to determine existing inventory of these devices and facilities' ability to absorb additional ventilators. Facilities must have sufficient staff, space, equipment, and supplies to utilize allocated ventilators adequately. At the time of an event, jurisdictions will need to verify and update information on facilities' capacity prior to making allocation decisions. Allocation of scarce life-saving resources during a pandemic should consider ethical principles to inform state and local plans for allocation of ventilators. In addition to ethical principles, decisions should be informed by assessment of need, determination of facilities' ability to use additional ventilators, and facilities' capacity to ensure access to ventilators for vulnerable populations (eg, rural, inner city, and uninsured and underinsured individuals) or high-risk populations that may be more susceptible to illness.