A person’s HIV transmission cluster—i.e., the group of people with whom their HIV strains are genetically linked—can yield clues about their potential to slip through the HIV care continuum, according to a large U.S. study.
The data, which were reported in Clinical Infectious Diseases, were derived from a retrospective study of 5,226 PLWH diagnosed in Los Angeles County between 2010 and 2014. They indicated that PLWH in genetically linked HIV transmission clusters that were growing rapidly spent more time virally suppressed before their viral load rebounded than those in slow-growing clusters. However, high-growth clusters were more likely to be composed of people with CD4 cell counts of ≥500 cells/ml at diagnosis than were slow-growth clusters.
“We acknowledge that cluster growth is influenced by access to and engagement with care, including HIV testing,” study authors noted. Once diagnosed, participants progressed through the care continuum at similar rates as others in their cluster: If others with a genetically linked virus took longer to become virally suppressed, so did they. Overall, median time between diagnosis and linkage to care was less than one month and diagnosis to viral suppression was six months.
Study authors suggested that services focused on HIV care linkage/restoration could place a priority on people within genetic clusters in which others have taken longer than usual to reach the next stage in the continuum, or had fallen out of care altogether.