Wastewater surveillance (WWS) is a valuable public health tool for detecting and monitoring infectious diseases, as it provides important information about changes in community-level disease trends, especially when combined with data from existing surveillance systems. WWS data allows health departments to target prevention efforts, a critical strategy to maximize limited resources and public health impact. In 2020, CDC established the National Wastewater Surveillance System (NWSS) to monitor COVID-19 trends in wastewater samples nationwide. This scale-up of WWS during the COVID-19 pandemic highlighted ethical considerations including privacy, stigma, data stewardship. It also underscored the importance of connecting surveillance efforts with public health action and prioritizing community engagement.
Anil T. Mangla, PhD, MS, MPH, FRIPH
Director of Disease Surveillance and Control,
Southern Nevada Health District
“Wastewater surveillance actually allows the jurisdictions to identify emerging threats, target interventions in very clear areas, and then allocate resources more efficiently. We often see the spikes in wastewater way before cases are clinically reported in hospitals or in clinics."
Listen to the full quote by pressing play below.
Public health agencies routinely encounter ethical issues and may face challenges addressing them. To enhance the effectiveness of WWS initiatives and build public trust, it is essential that public health staff understand potential ethical issues and have the tools to support decision-making.
Challenges addressing ethical issues may be due to several factors, including:
- Responsibility of ethical analysis: “Ethics work” can be intimidating and ineffective if perceived as individuals’ responsibility, rather than a systemic approach with infrastructures to support its implementation.
- Resources: Public health staff could benefit from increased time, support, and resources to effectively carry out ethical analysis and address complex issues.
- Reactive focus: Ethics are often seen as punitive, only a response to scandals or related to legal or regulatory issues, instead of being a proactive, essential part of effective public health.
- Trust: Building and fostering trust among communities that have significant mistrust in public health is no easy feat.
Key areas of ethical concern in WWS:
- Individual and group privacy concerns: WWS programs must carefully consider the scale necessary for surveillance, as small-scale wastewater sampling can increase the risk of privacy-related issues (e.g., individuals or groups being identified).
- Stigma: Surveillance findings can cause stigma if a disease or outcome is associated with an individual or group. To reduce stigma-related harm, WWS programs should ensure the protection and careful communication of information/data.
- Data stewardship: Without clear policies or guidelines, it can be unclear who owns the data or how it is shared. WWS programs can advance data stewardship by monitoring potential uses and misuses of data.
Transcript
This text is based on live transcription. Communication Access Realtime Translation (CART), captioning, and/or live transcription are provided to facilitate communication accessibility and may not be a totally verbatim record of the proceedings. This text is not to be distributed or used in any way that may violate copyright law.
NARRATOR:
Wastewater surveillance and testing allows us to detect and respond to increases in infectious diseases and target prevention efforts to communities that need it most to help prevent outbreaks. In 2020, with an urgent need for additional surveillance methods in response to the COVID-19 pandemic, public health turned to wastewater surveillance to support and inform the nation's response. As the use and visibility of wastewater surveillance has expanded, there is the potential for increased public health impact and a need for further attention to important issues with ethical dimensions.
In May of 2024, ASTHO convened partners engaged in wastewater surveillance to explore these issues and inform the development of ASTHO’s Framework for Addressing Ethical Considerations in Infectious Diseases: Public Health Wastewater Surveillance. These experts working in the field shared their insights on the importance of wastewater surveillance and why it is so critical to maintain ethics at the center of this work.
BRIAN LEFFERTS:
Wastewater testing is convenient for the public. It’s a non-invasive way to go about getting information from people. We don't need to ask the public to come in and get testing at a clinic.
LELIA GESSNER:
Wastewater monitoring is an important tool for infectious disease monitoring because it really strengthens the existing monitoring systems we have and complements existing information on clinical cases and emergency departments and allows us to better capture the community.
ANIL T. MANGLA:
Public health can actually use this tool, as in wastewater surveillance, to actually take its data and change it into public health action. Because, at the end of the day, you want some type of policy that is data-driven. Establishing ethical guidelines is also one of the key things as we move forward.
GESSNER:
There are so many different things that you can test for using wastewater, and there are a range of diseases and their spreads that we don't understand fully in a community. And so wastewater monitoring is really going to enhance our understanding of how diseases spread, so as we complement existing data systems for flu, RSV, it was able to be a useful tool for mpox. So I'm really excited about the expansion of different targets that we can monitor for an infectious disease. The other thing I'm really excited about in wastewater monitoring is the more data that we have and the longer these robust systems that we've built and continue to build have been around, the better we're going to understand the data, and the better we are going to be able to turn it into really useful public health action.
LEFFERTS:
What I'm most excited about when it comes to the future of wastewater surveillance is being able to utilize it to distribute resources or provide resources in a more equitable way. I think this is most important when we have limited resources. For example, in the region where I work we have some extremely high tuberculosis rates, and we don't have the ability to go out and test everyone everywhere to figure out who might have TB, or how to allocate those testing resources in treatment. But by using this population-level testing, we can figure out where the resources are needed the most and be able to provide those in a targeted way and in an equitable way.
GESSNER:
It's important that we conduct wastewater monitoring in a way that aligns with ethical principles because that's our responsibility as public health organizations, to use technology and tools to help everyone and to do that in an ethical way. And what we risk by not having these conversations and incorporating ethics into everything that we do is, you know, not only eroding public trust in organizations who are doing work that that is well-intentioned, but we also risk losing the ability to use this really valuable, transformational tool that is wastewater monitoring.
LEFFERTS:
We need the public's trust in order to be effective. Public health is not just scientific, it involves culture and involves values, and being ethical shows respect for individuals and it shows that we're making an effort to improve their well-being.
Anil T. Mangla, PhD, MS, MPH, FRIPH
Director of Disease Surveillance and Control,
Southern Nevada Health District
"A major ethical concern is the unplanned expansion of wastewater surveillance beyond its original public health intent, so for example, the use by law enforcement or private entities...The ethical wastewater surveillance must prioritize fair distribution of benefits and burdens, right? So this benefits, like we talked about, there's some burdens. Communication is most important. So findings must be communicated in a way that maintains scientific accuracy, avoids stigmatization, and empowers communities to take appropriate prevention action."
Listen to the full quote by pressing play below.
In 2025, ASTHO developed the "Framework for Addressing Ethical Considerations in Infectious Disease Public Health Wastewater Surveillance" to support public health departments and WWS partners in addressing ethical issues related to infectious disease WWS. Relevant literature, technical reports, and public health ethics frameworks/guidance inform this framework. The resource provides tools for ethical analysis to support public health practitioners’ decision-making, focusing on three areas of ethical concern in WWS: privacy, stigma, and data stewardship. Learn more about the development of a new framework.
Strengthening Public Health Response to Infectious Diseases Through Wastewater Surveillance
The expanded use of WWS has highlighted the importance of addressing potential ethical considerations. Ethical analysis plays a vital role in informing and justifying decision-making for public health activities. Recent workshops hosted by ASTHO supported select jurisdictions in building awareness of possible ethical issues related to WWS, and application of practical concepts from the Framework for Addressing Ethical Considerations in Infectious Disease Public Health Wastewater Surveillance to strengthen analytical capacity to support decision-making. This brief explores key WWS challenges and considerations discussed during the workshops including data management, communication, partnerships, and more.
This section highlights a successful and innovative solution that your peers implemented to address ethical considerations for WWS of infectious diseases. This story presents the factors that catalyzed the innovation, the existing policies or funding mechanisms that facilitated action, the potential barriers the organization faced, the collaborations and partnerships the organization leveraged, and tips for implementing and/or scaling the solution.
Colorado’s "Ethical Considerations for Wastewater Surveillance Systems" Training
Since 2022, the Colorado National Wastewater Surveillance System Center of Excellence (CO NWSS CoE) has served as a dedicated resource for WWS and communicable disease prevention. The CO NWSS CoE, a collaboration between the Colorado Department of Public Health and Environment (CDPHE) and the University of Denver, provides support and education to local and state public health agencies, wastewater utility partners, and public health laboratories within the U.S. Department of Health and Human Services regions 7 and 8.
Building off of ASTHO’s framework, the CO NWSS CoE developed and launched a course, Ethical Considerations for Wastewater Surveillance Systems. This helps public health and wastewater professionals improve their knowledge and understanding of ethical considerations related to WWS, and apply recommendations outlined in ASTHO’s framework while also providing practical insights and local examples for users.
Wastewater Testing for Arboviruses: Arizona’s Surveillance Approach
In Arizona, a pilot program is exploring wastewater surveillance to track arboviruses, including West Nile virus, dengue virus, and St. Louis encephalitis virus. Traditional surveillance methods often rely on clinical testing and mosquito monitoring, which can be resource-intensive, delayed, and may miss asymptomatic infections. This approach offers a complementary, community-level early warning system.
In response to ongoing arbovirus threats, the Arizona Department of Health Services launched a pilot program to detect viral activity in wastewater. Early results are encouraging, with trace detections identified using an in-house-developed multiplex assay. While these findings are promising, further validation, such as sequencing, is needed to confirm their significance and public health value.
The pilot program includes routine sampling in areas with varying levels of mosquito activity and relies on close collaboration among public health partners and utilities. It also emphasizes the development of communication tools to ensure clear and timely public health action.
Overall, this approach may help strengthen existing surveillance systems by adding another tool that provides earlier insights to support public health interventions and responses. To learn more read the blog post on Arizona's surveillance approach.
Transcript
This text is based on live transcription. Communication Access Realtime Translation (CART), captioning, and/or live transcription are provided to facilitate communication accessibility and may not be a totally verbatim record of the proceedings. This text is not to be distributed or used in any way that may violate copyright law.
[MUSIC]
SCREEN TEXT:
Collaboration in Action: One Health and Wastewater Surveillance. ASTHO connected with several states to discuss how they are approaching the One Health approach to wastewater surveillance. These conversations highlight the role of coordination and communication across sectors—from environmental and public health to community partners—and the impact that collaboration has had on strengthening their efforts. 2025.
QUESTION:
Tell us about the wastewater surveillance program in your jurisdiction and what pathogens your jurisdictions survey using wastewater?
JOLI WEISS:
In Arizona, we participate in CDC's National Wastewater Surveillance Program, and we have 25 sites in Arizona in eight different counties. So, we cover about 50% of our population.
JAMIE MIDDLETON:
Currently, Los Angeles County was also awarded funding to start their own wastewater surveillance program. We will be utilizing metagenomic sequencing, which will allow us to test all of the genetic material within the wastewater. So one test will be able to identify many different pathogens at the same time at a single cost.
QUESTION:
What partners are engaged in wastewater surveillance efforts, and how is messaging handled?
WEISS:
We work closely with other epidemiology programs, in particular our respiratory disease program and our vector zoonotic disease program, our local county public health partners, as well as environmental health partners, city officials, Department of Agriculture, and Department of Game and Fish.
CHANTELLE BATTON:
So we work closely with our local health authority partners. We send them wastewater surveillance data weekly and also do program updates monthly with our local health authority partners and our laboratories.
HANNA OLTEAN:
We have a community-facing dashboard that shares information with the public regarding epidemiology findings and wastewater. We also have an internal-facing dashboard that's important for public health partners so local health jurisdictions can compare wastewater-based epidemiology findings with other surveillance parameters.
QUESTION:
How does your jurisdiction implement a One Health approach to wastewater surveillance and what are the benefits and challenges of using the One Health approach?
BATTON:
Through One Health, we've been able to establish great partnerships that we wouldn't have been able to before, and we were able to create a One Health team. With that team, we've worked with the Nevada Department of Agriculture, Nevada Department of Wildlife, universities, 4-H extensions to really build that framework.
WEISS:
It's been really beneficial to have all those partners help us make decisions about how to interpret results and determine what targets we want to look at to bring on board.
In particular, for H5, it was very helpful to speak with our Game and Fish partners to look at migratory bird patterns. So when we got our first positive in our wastewater, we asked: was that also correlating with our migratory bird patterns?
OLTEAN:
To date, we do not have sampling for a zoonotic pathogen in our wastewater. However, in anticipation of bringing on influenza A H5 subtyping, we have been doing quite a bit of planning from a One Health perspective. This will include a presentation at our One Health collaborative meeting, which engages Departments of Agriculture, Departments of Fish and Wildlife, and different environmental public health groups to make sure that everyone is aware and understands the types of data collection that's happening, as well as results and interpretation—how those results will be messaged and the ways that we'll need to collaborate in both planning and response efforts.
MIDDLETON:
Some of the challenges with wastewater scanning are that it's so new that it is difficult to understand baselines. One of the things that may help us with that is our metagenomic analysis, which will help us to understand a lot of pathogens—especially zoonotic pathogens—that may go misdiagnosed or underdiagnosed, and to start creating some of those baselines.
QUESTION:
Are there any One Health success stories you'd like to highlight?
BATTON:
We detected H5 in the wastewater before we even had any dairy herd illnesses, before we had any human detections. We were able to work with our Department of Agriculture and Department of Wildlife to pinpoint where those detections were coming from. We were able to actually pinpoint exactly what dairy that was coming from. And so with that One Health approach, we were able to minimize the dairy impacts but also the human health impacts together.
MIDDLETON:
On October 28, 2024, we had a wastewater detection for an area that services about 4.8 million people. What was interesting about this positivity is that it was higher than any of the other wastewater sites since the inception of the program in May 2024.
DE ST MAURICE:
For our human component, we first looked at our emergency department data to see if our syndromic surveillance unit was picking up additional detections. We also looked at our electronic lab reporting data for influenza, and we saw that in areas serviced by that sewershed, we didn't see any increases in influenza A positivity, suggesting that this wasn't driven by humans.
MIDDLETON:
We do have a closed wastewater system, so we realized that this detection was not likely due to migratory birds or wild birds. There were no dairies or poultry industry local to those areas, but there were a lot of processing plants. We had mapped out all of the dairy and poultry processing sites. This data was really helpful for looking at this sewershed and finding that there were 16 different processing facilities that processed within the sewershed. We roughly estimate about 800,000 gallons of milk product is brought in on a daily basis.
We didn't have positivity in any of the dairy herds in Los Angeles County during that time. Where we do import from in the Central Valley had about 500 infected dairies at that time. So that would help explain the sudden very high increase in H5 detection in wastewater.
SCREEN TEXT:
Thanks for watching! For more information on ASTHO's work, please visit www.astho.org.
Hear More From Program Staff
Peggy Honein, PhD, MPH
Director of the Division of Infectious Disease Readiness and Innovation,
CDC
“So for an infection like COVID, where a lot of people had asymptomatic infection and now fewer and fewer people go to healthcare and get tests, wastewater gives us really important insights into what's happening that we wouldn't get only from people who have laboratory tests for COVID.”
Listen to the full quote by pressing play below.
Allison Wheeler, MSPH
Manager, Wastewater Surveillance Unit,
Colorado Department of Public Health and Environment
"So it was in early August where we detected measles genetic material in a wastewater sample from Grand Junction. And 1st we detected a really low level detection and then the sample directly after that. Since wastewater utilities submit 2 samples per week, that was a very high level detection. And so we were pretty sure that this indicated a community transmission of measles in Grand Junction. So we reached out to our Mesa County public health partners and alerted them of these wastewater detections. And their first response was, we don't have any measles cases. And we said, yeah, but we think there might be something going on. And so we would recommend at a minimum reaching out to your healthcare providers to remind them that measles is indeed circulating in Colorado and to remind them of the symptoms and to not hesitate to test patients that presented with those symptoms. And so sure enough, two days later they identified their first case, and then after that they identified and a total of 11 cases that were part of that outbreak."
Listen to the full quote by pressing play below.
Allison Wheeler, MSPH
Manager, Wastewater Surveillance Unit,
Colorado Department of Public Health and Environment
"I think one of the things that that we learned is that we need to involve our vaccine preventable disease team and our health department leadership early on in the process of bringing on a new target to make sure that they support surveillance for, you know, in this case, vaccine preventable diseases and wastewater. If they don't, you know, we we're, we would be collecting this data with no one using it. And, and we don't want to do that. And so the other thing that we've really learned is that we need to teach our internal teams how to use and interpret the data. It it's not very intuitive if you're not familiar with this viral concentration data in wastewater. So we really encourage their participation in calls with our team, our wastewater surveillance team and also with local health departments so that they can explain the clinical relevance of what we're finding in wastewater. And then I would say, I encourage all folks that are even interested, you know, we have teams here at CDPHE that reach out to us that say, hey, we're interested in seeing if we could do wastewater surveillance for X pathogen. Can you do that? And so we talk through it to see if it's even viable, if it fills any surveillance gaps, of course, if that pathogen is even shed in wastewater, and what value it would bring to their current surveillance system."
Listen to the full quote by pressing play below.
Policies and Funding
CO NWSS CoE developed this course with funding from the CDC’s Epidemiology and Laboratory Capacity (ELC) program, specifically NWSS 2. The course took approximately 4.5 months to develop, from initial conversations to publication.
Challenges and Barriers
- The partnership between CDPHE and the University of Denver, along with engagement with external subject matter experts (SMEs), allowed the CoE to tap into a robust network of expertise; however, it also introduced challenges inherent to collaboration, such as developing a shared vision and priorities.
- The CO NWSS CoE team also experienced challenges related to communicating complex information in plain language, without losing or changing the message. They actively engaged team members who had not previously participated in ethics-related discussions, valuing their fresh perspective to help review materials and flag potential areas of confusion.
Collaboration and Partnerships
Several key partners collaborated on this important training course. In addition to the CO NWSS CoE staff, other key contributors and collaborators include a graduate student from the University of Denver College of Professional Studies in the Instructional Design and Technology program, the University of Denver video production team, and CDPHE wastewater surveillance staff. The course also features feedback from external SMEs who were key in developing ASTHO’s framework, and members of the CO NWSS CoE Advisory Board – consisting of infectious disease physicians, wastewater utility partners, academic partners, and local public health staff – also reviewed the course.
Tips for Implementation and Scaling from the CO NWSS CoE Staff
- Community needs: Conduct surveys or focus groups to determine training needs and gaps, and establish a clear channel of communication with communities where surveillance is conducted to understand their perspectives.
- Audience: Discuss the target audience for the training, identify promising practices or strategies that resonate with that audience, and routinely engage members of your target audience throughout the development process.
- Goals and objectives: Set clear, well-defined goals and objectives to minimize scope creep.
- Collaborators: Work with a variety of SMEs, relevant partners, and community organizations to ensure training is relevant for users and community needs are met.
- Ongoing feedback: Establish regular opportunities to gather feedback and suggestions during the planning, implementation, and evaluation phases of the training.
- Tailor content: Develop examples or case studies specific to your state/region to contextualize the content and make it most relevant to your audience.
APPLYING THIS KNOWLEDGE TO INFECTIOUS DISEASE
Developing relevant training programs and resources can help WWS programs implement public health ethical analysis for infectious disease monitoring and response.
-
- Enhanced training: High-quality content can provide engaging and effective training materials, improving staff understanding and retention of complex ethical considerations as well as key infectious disease concepts.
- Fostering collaboration: The successful collaboration for CO NWSS CoE underscores the importance of partnerships for ethical WWS for infectious diseases. This could encourage more partnerships between health departments, academia, wastewater utilities, public stakeholders, and other relevant organizations.
- Scaling effective practices: The strategies and practices outlined in CO NWSS CoE course can be scaled and adapted for use in other jurisdictions, enhancing overall infectious disease efforts.
- Planning for future threats: Insights from CO NWSS CoE course can help health departments better prepare for future infectious disease outbreaks, enhancing their ability to respond effectively and ethically.
This section encompasses a collection of pertinent tools and resources curated from ASTHO's Public Health Innovations Catalog and various other sources to help you navigate and comprehend the intricacies of this subject area. Garner insights and experiences from your peers, enabling you to start building solutions tailored to your health department.
Feeling inspired to address the unique challenges facing your department? With just one click, you can better understand your department's specific gaps and craft a persuasive action plan to present to your leadership and partners.
or explore the other focus areas:
Workforce Training & Resources Data Systems & Management Equity
Email the preparedness team with questions or comments at preparedness@astho.org.