How Wastewater Surveillance Works

Wastewater surveillance can help communities detect and prepare for increasing cases of COVID-19. Data are available quickly, 5 to 7 days after the toilet flush.

Step 1. People with COVID-19 can shed the virus in their feces (poop), even if they don’t have symptoms.
  1. People with COVID-19 can shed the virus in their feces (poop), even if they don’t have symptoms.
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Step 2. The virus in poop is flushed down the toilet and travels through the sewage system.
  1. The virus in poop is flushed down the toilet and travels through the sewage system.
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Step 3. Before wastewater is treated, wastewater technicians take samples to get information about the virus.
  1. Before wastewater is treated, wastewater technicians take samples to get information about the virus.
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Step 4. Laboratories test for the virus and measure virus levels in the wastewater.
  1. Laboratories test for the virus and measure virus levels in the wastewater.
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Step 5. Public health officials use wastewater data to better understand COVID-19 trends in communities and make decisions.
  1. Public health officials use wastewater data to better understand COVID-19 trends in communities and make decisions, such as where to have mobile testing and vaccination sites.