HIV Cluster Detection and Response in Action: Stories from the Field

HIV Cluster Detection and Response in Action: Stories from the Field

Using new tools and strategies, public health departments can detect and respond to “clusters” and “outbreaks” of HIV infections faster than ever before. These techniques allow public health officials to bring services and support to affected communities and prevent new infections.

HIV cluster detection and response (CDR) represents a key pillar in the federal government’s initiative, Ending the HIV Epidemic in the U.S. The level of response can be scaled up or down to address the needs of a particular cluster or outbreak.

Cluster detection

There are several ways a cluster may be identified. A healthcare provider might notice an increase in new HIV diagnoses and notify the health department, or public health staff conducting partner services interviews might find an unusual number of new diagnoses among people who are linked through sexual or drug-injecting partnerships.

Sometimes, clusters might not be apparent until public health staff review and analyze reports of new diagnoses from across a city, county, or state. Doing so can reveal increases in HIV diagnoses. A cluster may also be found using molecular analysis, which involves the comparison of molecular data from drug resistance testing to identify groups of infections that are very similar.

Cluster response

Once an HIV cluster is detected, the next step is to understand more about it so that public health agencies can provide resources and support such as partner services interviews to identify and offer testing to people who are part of the network and might have been exposed to HIV. People with HIV are then linked to care, treatment, and social services, while people who test negative are offered prevention tools, such as PrEP or referred to services, such as syringe services programs. This response often engages a wide range of healthcare providers, advocates, and other community leaders who work together to design interventions that address the community’s specific needs. Community responses to HIV clusters can have long-lasting benefits that extend beyond the initial group of people who were affected and can increase services to a wider community.

By using traditional HIV prevention approaches (e.g., testing, treatment, PrEP, and syringe service programs) in a more focused way, each cluster response effort can speed the delivery of services to people who need them most. It can also strengthen a community’s overall prevention infrastructure and bring the nation one step closer to ending the HIV epidemic.

Community Spotlights

These community spotlights offer a glimpse at cluster and outbreak detection and response efforts across the nation, highlighting a range of cluster detection tools, cultural contexts, and community benefits.

  • In San Antonio, TX, an HIV cluster among young Latino gay and bisexual men was first identified using molecular detection. This discovery inspired a community-wide collaboration resulting in increased testing, PrEP access, and treatment support.
  • In Lawrence and Lowell, MA, an HIV cluster among people who inject drugs, many experiencing homelessness, was first noticed by a community health provider. Further exploration by health officials resulted in response efforts including expanded syringe services programs across the state.
  • In Minneapolis, MN, an HIV cluster was concentrated among people who inject drugs and were experiencing homelessness, the majority of whom were Native American. Initially observed by community health workers and confirmed by state health officials using surveillance data, identification of this cluster allowed a clinic already practicing culturally competent care to provide HIV prevention and care services directly to its clients instead of referring them to other facilities.

Despite differences, the stories are linked by a strong common thread: in each case, detection of the cluster exposed profound unmet community needs and catalyzed urgent efforts to implement more effective approaches to HIV prevention. The experiences of community leaders and health officials involved in these responses can provide a model to others seeking to implement long-lasting changes that will benefit entire communities.