A Breakthrough in Detecting Cancer-Causing Viruses
For the first time, scientists have successfully identified and tracked all the primary viruses linked to tumour development through wastewater analysis. This groundbreaking discovery has the potential to revolutionize prevention strategies, health monitoring, and the surveillance of oncogenic infections within communities.
The study, led by Anthony Maresso and Justin Clark from the Baylor College of Medicine and published in Applied and Environmental Microbiology, was conducted in collaboration with the University of Texas Health Science Center at Houston. Researchers collected and analyzed wastewater samples between May 2022 and May 2025 from over 40 sites across 16 cities in Texas, covering approximately a quarter of the state’s population. They used an advanced genetic sequencing technique called “hybrid-capture,” which can detect more than 3,000 known human viruses and identify potential new mutations in a single test.
The Role of Oncogenic Viruses in Cancer
According to the researchers, oncogenic viruses may be responsible for around one in five cancers globally. Some of the most well-known examples include the human papillomavirus (HPV), which is associated with cervical and throat cancers, and hepatitis B and C viruses, which are linked to liver cancer.
“Oncogenic viruses can cause around one in five cancers worldwide,” said Anthony Maresso, a professor of molecular virology and microbiology. “Since these infections often remain asymptomatic for years or even decades, many people do not realize they are infected until the tumour develops. This makes it very difficult to implement early preventive interventions.”
The wastewater analysis revealed the presence of all major oncogenic viruses currently known, including HPV, hepatitis B and C viruses, cancer-associated polyomaviruses, Epstein-Barr virus, and the herpesvirus linked to Kaposi’s sarcoma.
Rising Trends in Oncogenic Viruses
Over the three-year period of monitoring, the researchers observed a significant increase in the presence of several oncogenic viruses. In particular, HPV, Epstein-Barr virus, and some polyomaviruses showed marked rises after 2024.
The team is still investigating the reasons behind this increase, but possible factors could include the resumption of travel, increased interpersonal contact, and the end of social distancing measures during the COVID-19 pandemic.
Focus on Human Papillomavirus
Human papillomavirus received special attention in the study. “There are hundreds of HPV types, but only some are considered high-risk for cancer,” explained Justin Clark. “HPV-16 and HPV-18 together cause more than 70% of cervical cancers worldwide.”
The study found that low-risk HPV variants were more widespread, but high-risk variants also saw a significant increase between late 2024 and early 2025. HPV-16 was consistently more common than HPV-18, aligning with previous international clinical studies.
Implications for Vaccination Monitoring
Another key finding involves the Gardasil 9 vaccine, which targets nine HPV types. All nine HPV types included in the vaccine were detected in wastewater. According to the authors, this could enable environmental monitoring to assess the effectiveness of vaccination campaigns in real populations.
“Our study shows that tumour-associated viruses can be monitored through wastewater,” Maresso concluded. “This opens up new opportunities to better understand the relationship between these viruses and the human population and to develop more effective public health strategies.”
