Wastewater Data for Rapid Outbreak Response

Identifying potential measles cases

In 2025, as measles outbreaks emerged across the country, health departments and their partners deployed laboratory tests to detect measles virus in wastewater in some communities across the United States. This type of testing alerted health officials about potential measles cases days to weeks before health department confirmed the first case in a community. This forewarning provided time for healthcare providers and public health officials to take action that would potentially limit the spread of measles.

Texas

In West Texas, wastewater data provided critical community-level insights into the spread of measles. In El Paso, detecting measles in wastewater gave the local health department a one-week lead before they had information from case investigations. This allowed them to alert local hospitals to potential cases, stand up an emergency operations center, and expand rapid access to measles testing and vaccination. These efforts were especially important because measles is highly contagious.

South Carolina

In South Carolina, the Department of Public Health's Wastewater Surveillance Program supported the state's response to a measles outbreak in Spartanburg County by rapidly expanding measles wastewater testing. CDC's rapid deployment of laboratory tests meant that South Carolina could expand measles testing to 12 wastewater monitoring sites across the state within the first month. Coordination with North Carolina public health colleagues also strengthened wastewater monitoring response along the states' border communities.

Sequencing at the Colorado Wastewater Monitoring Center of Excellence confirmed that the measles virus detected in South Carolina wastewater samples belonged to the same genetic strain found in other areas of the United States experiencing outbreaks, illustrating how the virus was spreading through communities at high risk for infection. This effort shows how states can rapidly scale up wastewater monitoring to support outbreak response and the value of CDC's Center of Excellence network. Public health departments can integrate wastewater data into existing public health monitoring efforts to understand infectious disease risks and inform prevention and control.

Informing public health decision-making

California

When Los Angeles County, California experienced an outbreak of hepatitis A, public health officials turned to data from both clinical and wastewater sources. The initial cases occurred among people experiencing homelessness, a population that faces barriers to accessing care. The rise in wastewater concentrations was greater than the number of reported cases, which indicated potential unreported spread of the virus and supported initiating a broad community outbreak response. Continued monitoring of hepatitis A wastewater concentrations helped assess the effectiveness of public health measures to control the outbreak.

Kansas

In 2024, a county in Kansas experienced an outbreak of hepatitis A. When a neighboring community detected hepatitis A in wastewater, public health officials were concerned that the outbreak may have spread. Health officials issued a health advisory to healthcare providers in the community to share information about hepatitis A and encourage providers to stay alert for cases of hepatitis A. This alert helped providers monitor and prevent further spread of the disease.

Strategic use of monkeypox virus data

Texas

During the monkeypox virus outbreak that began in 2022, Houston, Texas launched a new, adaptive sampling approach to monitor for monkeypox virus in the community. One "sentinel site" was chosen for weekly testing. If the virus was detected at the sentinel site, the city scaled up testing to include all wastewater treatment plants. If there were no positive detections for four weeks, testing scaled down and returned to just the sentinel site. This flexible approach helped monitor any potential spread of monkeypox across the city, while also directing resources to the areas at highest need for intervention.

Nevada

Nevada took a different approach to using wastewater data to make data-informed public health decisions. Public health officials in Las Vegas used wastewater detections of monkeypox virus to inform strategic community outreach by offering vaccinations and additional information to people at higher risk for infection.

Additionally, in July 2025, Nevada partnered with the University of Nevada, Las Vegas (UNLV) to develop an express testing clinic for sexually transmitted infections to respond to wastewater detections of chlamydia and gonorrhea. This clinic has high utilization and has resulted in increased testing in the area, with the goal of finding cases earlier to help prevent any further spread of disease caused by these infections.