Researchers at Baylor College of Medicine and collaborating institutions announced on June 15 that they have developed a novel method for detecting human immunodeficiency virus 1 (HIV-1) in community wastewater. The approach, called hybrid-capture genetic sequencing, enables detailed analysis of viral genomes and identification of HIV signals originating from wastewater samples.
The study found that the presence of HIV signals in wastewater closely matched the number of people known to be living with HIV in those communities. This suggests that wastewater surveillance could serve as an effective tool for tracking the local burden of HIV. Current surveillance methods rely primarily on clinical diagnoses and reporting by individuals who access care, leaving undiagnosed or untreated cases largely untracked.
"There is an urgent need for a complementary surveillance strategy capable of detecting undiagnosed or untreated infections," said Dr. Anthony Maresso, professor of molecular virology and microbiology at Baylor College of Medicine. "In the current study, we show that wastewater analysis may offer the possibility of finding geographic locations with untreated HIV. This would help identify communities where resources for HIV prevention and treatment need to be present or increased."
Since May 2022, the Texas Wastewater and Environmental Biomonitoring group has conducted regular viral sequencing across major Texas cities, identifying more than 400 human and animal viruses in local wastewater samples. The researchers analyzed over 2,000 samples from 40 sites across 15 cities between mid-2022 and late 2024 using advanced sequencing techniques.
Dr. Justin Clark, assistant professor at Baylor College of Medicine, said, "Instead of using tests that look only for short specific genetic sequences of HIV, we used an advanced sequencing approach that allowed us to detect HIV genetic material and examine which sections of the HIV genome were present." While some detected sequences appeared to originate from non-circulating lab strains—suggesting contamination—the team developed a classification system to distinguish between circulating community-derived strains and vector-derived ones used in research settings.
The researchers emphasized maintaining site anonymity due to ongoing stigma around HIV diagnosis. "We have another component of this study – reaching out to focus groups, communities, individuals and advocates to make sure we take into consideration people's points of view," said Giordano. Maresso concluded, "This study establishes a foundation for sequencing-based HIV wastewater surveillance and highlights lentiviral vector contamination as an overlooked confounding factor that must be addressed in future monitoring efforts for HIV-1 and other disease-causing microbes with synthetic counterparts."
