This year, another “tripledemic” seems inevitable–unless we proactively work to prevent and prepare for it. By monitoring the population for RSV and the flu before the season starts, we can respond fast when it is needed. The crucial tool we have to do this lies within each and every one of us—literally. Every time we flush, we are sending out into the world a sample that can provide a vital measure of the population’s health.

Wastewater-based epidemiology (WBE) is a reliable, nonintrusive, and relatively inexpensive way to track the spread of disease. By testing for the presence of dangerous pathogens or chemicals found in sewage, we can get a real-time picture of the health of a community. This trick has been used to track the spread of COVID-19, the poliovirus, monkeypox virus, and norovirus, as well as to measure high-risk substance use in communities, such as fentanyl, xylazine, and other opioids. The information has helped empower decision-makers to prepare for potential outbreaks and to act earlier–—whether that be prepping hospitals for a potential surge or implementing remote-work policies.

However, we are still in a place where many of these steps are implemented after public health crises are already underway. Not just shutting the stable door after the horse has bolted, but after the horse has bolted, met a nice other horse, had a bunch of little baby horses with them, and now they’re all back and eating our picnic. Last year, nearly 40% of U.S. households reported experiencing either COVID-19, the flu, or RSV in January—and RSV became the leading cause of lower-respiratory- tract-related hospitalization in children under one. Hospitals were filled and lives were lost.

As we saw with COVID-19, wastewater can be used to detect changes in RSV infections in the community before other monitoring systems can pick them up. By proactively testing our wastewater for RSV and the flu this season, we can be better prepared for a tripledemic—and let folks know what is going on in their communities. This approach can limit infection rates and hospitalizations, and, most importantly, save lives.

This cold and flu season, we’ll have an RSV vaccine available for people 60 years and older for the first time. Some may say that means we don’t need monitoring in place when there’s a preventative tool at our disposal, but that is simply untrue. In fact, WBE has an even more important role to play in our public health response as new vaccines are introduced. WBE can help to let us know where vaccines are most needed and even give insight on whether vaccines are effective against asymptomatic carriage of viruses like COVID-19.

We can get this tool into the hands of more public officials nationwide. The federal government can make funding available for cities and states to implement WBE programs and train staff. Several programs part of the Pandemic and All Hazards Preparedness Act (PAHPA) expired in September and the timeline for the reauthorization of this legislation is unclear. I hope to see the next iteration of PAHPA include WBE and empower agencies like ASPR and CDC to invest in wastewater surveillance as a pandemic preparedness and early warning tool.

By testing for viruses like influenza and RSV, we can significantly improve public health across our country and completely reimagine how our cities, hospitals, and families prepare for and deal with cold and flu season.

We also need to ensure that wastewater data is reliable, up-to-date, and comparable across regions, for instance, through the CDC’s National Wastewater Surveillance System (NWSS). It would allow public health officials to make informed decisions about how to respond to potential outbreaks.

For far too long, public health funding has existed in a cycle of panic and neglect: During a crisis, we invest heavily in needle-moving research and experimentation that bears great fruit, but the funding quickly dries up as urgency wanes. It is time we break this cycle. By investing in proactive wastewater monitoring, we can provide the nation and public health officials with a critical tool to prevent the next pandemic. Good data saves lives–and the time to act is now.

Bill Hanage is an associate professor at the Harvard T.H. Chan School of Public Health.

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