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Biological & Public Health

Wastewater Surveillance

3 min read

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.

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Use this page to understand Wastewater surveillance. Use the live dashboard to see current alerts, infrastructure stress, weather, wildfire, travel, public-health, supply-chain, and stability indicators in one place.

Quick answer / What to check next

Quick answer

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.

What this signal means

It gives a community-level context signal for COVID-19, Influenza A, and RSV when CDC WVAL data is available.

What to check on HazardNow

pathogen, WVAL category, reporting geography, latest week, and whether a High or Very High category is present.

Verify with official source

CDC Wastewater Viral Activity Levels

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.

Source
Time
Place
Scope

Official sources to verify

Use these links to verify current source text, update timing, and agency caveats.

Last reviewed: . This page explains general preparedness information and does not replace official instructions.

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.

Related terms

Check the live HazardNow dashboard

Use this page to understand Wastewater surveillance. Use the live dashboard to see current alerts, infrastructure stress, weather, wildfire, travel, public-health, supply-chain, and stability indicators in one place. Focus on biological-surveillance, respiratory-illness-activity, hospital-respiratory-admissions in the live view.