An outbreak detection program has identified the measles virus in Houston wastewater samples collected in early January 2025, before any cases were reported. This initiative involves researchers from Baylor College of Medicine, the University of Texas Health Science Center – Houston, the Houston Health Department, and Rice University. Their findings have been published in the American Journal of Public Health.
The team used a sequencing-based approach to detect the virus, analyzing genetic material with high sensitivity and specificity. This method could be significant for public health as it may serve as an early warning system for viral outbreaks. The study is particularly relevant given the rising number of measles cases in Texas and across the United States.
Dr. Anthony Maresso from Baylor explained that "systematically sequencing the genetic material in wastewater reveals dynamic changes in human viruses circulating in a community." He added that this approach can improve understanding of outbreaks and help inform public health strategies.
The study reported that on January 7, samples from two Houston water treatment facilities showed traces of the measles virus. A subsequent investigation confirmed infections in two travelers living in areas serviced by these facilities on January 17.
Dr. Sara Javornik Cregeen noted that they validated their findings with a second method through collaboration with local institutions: "They tested for the virus presence in samples from the same date and collection site and confirmed the signal using another technique, PCR."
Dr. Michael Tisza highlighted ongoing efforts to monitor measles outbreaks elsewhere: "With lessons learned from the Houston measles detection event, we are now working with our public health partners to gather data on the current measles outbreak in West Texas."
Currently, no traces of measles are being detected in Houston's wastewater; however, they continue to monitor other locations such as West Texas cities. The research team provides updates through a publicly available health dashboard at https://tephi.texas.gov/early-detection.
Dr. Eric Boerwinkle emphasized that this work demonstrates how sophisticated wastewater analyses can benefit public health by preventing outbreaks: “This work underscores the ability of sophisticated wastewater analyses to serve as an early detection system benefitting public health.”
He also stressed that vaccination remains crucial: “The best protection from contracting the measles virus is the MMR vaccine, which has been shown to be safe and effective.”
