HIV Cluster and Outbreak Detection and Response: The Science and Experience

Abstract

The Respond pillar of the Ending the HIV Epidemic in the U.S. initiative, which consists of activities also known as cluster and outbreak detection and response, offers a framework to guide tailored implementation of proven HIV prevention strategies where transmission is occurring most rapidly. Cluster and outbreak response involves understanding the networks in which rapid transmission is occurring; linking people in the network to essential services; and identifying and addressing gaps in programs and services such as testing, HIV and other medical care, pre-exposure prophylaxis, and syringe services programs. This article reviews the experience gained through 30 HIV cluster and outbreak responses in North America during 2000−2020 to describe approaches for implementing these core response strategies. Numerous jurisdictions that have implemented these response strategies have demonstrated success in improving outcomes related to HIV care and viral suppression, testing, use of prevention services, and reductions in transmission or new diagnoses. Efforts to address important gaps in service delivery revealed by cluster and outbreak detection and response can strengthen prevention efforts broadly through multidisciplinary, multisector collaboration. In this way, the Respond pillar embodies the collaborative, data-guided approach that is critical to the overall success of the Ending the HIV Epidemic in the U.S. initiative.

Clusters of Rapid HIV Transmission Among Gay, Bisexual, and Other Men Who Have Sex with Men — United States, 2018–2021

“…These jurisdictions are supported in these analyses by programs made available by CDC and can detect, analyze, and visualize clusters using a bioinformatics tool called Secure HIV-TRACE. https://www.cdc.gov/hiv/funding/ announcements/ps18-1802/guidance-relateds.html ¶ ¶ ¶ https://www.cdc.gov/hiv/statistics/systems/nhbs/index.html qualitative interviews, and medical record abstraction), to better and more quickly understand affected populations and identify service gaps experienced by persons in these clusters (4,7). Gathering additional quantitative or qualitative data is important to understand and address the differing needs of persons in networks experiencing rapid transmission, including sexual, gender, and racial and ethnic minority groups involved in each cluster.…”

“…Most clusters of rapid HIV transmission occur among MSM. Swift response to reach diverse persons and communities with early, tailored, and focused interventions is essential to reducing HIV transmission ( 4 ).…”

An outbreak of HIV infection among people who inject drugs in northeastern Massachusetts: findings and lessons learned from a medical record review

“…Our findings demonstrate that medical record review in the context of an outbreak investigation can benefit health jurisdictions without integrated infectious disease management systems by providing data on co-occurring conditions or clinical indications of early diagnosis. Medical records data can also suggest structural barriers to accessing services, missed opportunities for public health intervention and can facilitate exchange of information between surveillance and field staff needed to identify possible factors for transmission [ 22 , 25 ]. Secondary benefits may include strengthening relationships between public health and clinical providers to improve efficiency in identifying and addressing emergent public health problems.…”

Forecasting HIV-1 Genetic Cluster Growth in Illinois,United States

“…11 The Centers for Disease Control and Prevention (CDC) classifies clusters as priority based on recent formation and the number of new diagnoses joining the cluster within the previous year. 13 In this article, we compare these and other prioritization schemes to determine which best predicted future cluster growth using Illinois HIV genotypes collected as part of routine public health surveillance activities since 2012. 14…”