Biological & Public Health
Wastewater Surveillance
Wastewater surveillance can detect viral activity in a community before or alongside clinical reporting because it measures viral signals in wastewater systems rather than individual diagnoses.
Quick read
- Useful for
- It gives a community-level context signal for COVID-19, Influenza A, and RSV when CDC WVAL data is available.
- Watch
- pathogen, WVAL category, reporting geography, latest week, and whether a High or Very High category is present.
- Confirm with
- CDC Wastewater Viral Activity Levels and CDC Respiratory Illnesses
- Remember
- Wastewater is not patient-level data, is not a diagnosis, and coverage can be uneven across communities and pathogens.
How HazardNow reads WVAL
CDC Wastewater Viral Activity Level categories run from Very Low and Low through Moderate, High, and Very High. HazardNow uses those categories for public-health situational awareness and does not display them as personal medical guidance.
- Very Low
- Low
- Moderate
- High
- Very High
Default elevated rule
- High and Very High count as elevated.
- Moderate is watch/context by default.
- A state or reporting area can be elevated for one pathogen and not another.
- Wastewater data can lag, change with reporting coverage, and represent a broad community rather than every neighborhood.
Visual reference
Wastewater surveillance signal map
Read the signal as one layer in a larger source stack, not as a standalone instruction.
Official/public sources
Use these links to verify current source text, update timing, and agency caveats.
FAQ
Can a state be elevated for one pathogen and not another?
Yes. COVID-19, Influenza A, and RSV can move differently by season, geography, reporting coverage, and current transmission pattern.
Does WVAL describe individual risk?
No. It is a public surveillance indicator for broad community activity, not patient-level testing or diagnosis.
Why is Moderate not counted as elevated by default?
HazardNow reserves the default elevated count for High and Very High so the header card stays focused on stronger signals. Moderate remains useful watch/context.