{"id":14095,"date":"2022-04-08T17:24:42","date_gmt":"2022-04-08T21:24:42","guid":{"rendered":"https:\/\/www.vdh.virginia.gov\/environmental-health\/?page_id=14095"},"modified":"2023-06-13T10:54:07","modified_gmt":"2023-06-13T14:54:07","slug":"frequently-asked-questions","status":"publish","type":"page","link":"https:\/\/www.vdh.virginia.gov\/environmental-health\/wastewater-surveillance-for-covid-19\/frequently-asked-questions\/","title":{"rendered":"Frequently Asked Questions"},"content":{"rendered":"

 <\/p>\nWhat is wastewater?<\/b><\/span>

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Wastewater, also known as sewage, is used, dirty water from homes (toilets, sinks, kitchens, and laundries) and from other facilities like restaurants, schools, and office buildings that is collected through a series of pipes and manholes and directed to a wastewater treatment plant. The sewage is treated by the wastewater treatment plant so that it may be safely returned to the environment. Wastewater is not the same as clean drinking water, which is water from a stream or well that is highly treated by a water treatment facility before flowing into homes and businesses. <\/span><\/p>\n<\/div>\n

\nWhat is wastewater surveillance for SARS-CoV-2?<\/span>
<\/b><\/p>\n

Wastewater surveillance is the monitoring of wastewater for the viral particles of SARS-CoV-2, the virus that causes COVID-19. When a person is infected with a SARS-CoV-2 virus, the virus is shed into the person\u2019s digestive tract and out with their feces. Wastewater samples are collected at the wastewater treatment facilities and analyzed in the lab for SARS-CoV-2. Public health can use this information to estimate whether the levels of community infection are going up or down.<\/span><\/p>\n<\/div>\n

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<\/b>What are the benefits of wastewater surveillance for COVID-19?<\/span>

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This surveillance can let us know how much COVID-19 might be in the community. This means a single sample can give an estimate of infection across the whole community and include both symptomatic (have symptoms) and asymptomatic (do not have symptoms) cases. Routinely monitoring these locations can give approximate infection trends in the community. It is cost effective as it does not require clinical patient testing.<\/span><\/p>\n<\/div>\n

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<\/b>How do you measure COVID-19 trends using wastewater surveillance?<\/span>

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SARS-CoV-2 (the virus which causes COVID-19) has RNA. The Polymerase Chain Reaction (PCR) technology can be used to determine the amount of viral RNA in the wastewater. By routinely measuring how much virus is in the wastewater, we can look at how the virus amount changes over time and look for trends. The amount of the virus in the wastewater is related to how many people have COVID-19 and are shedding the virus in their feces, whether they feel sick or not. A single sample collected at a treatment plant provides an indicator of the trends of COVID-19 infections in the community served by the treatment plant (the sewershed).<\/span><\/p>\n<\/div>\n

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<\/b>What is a \u2018sewershed\u2019?<\/span>

<\/b><\/p>\n

A sewershed is the entire network of sewer pipes that flows into a wastewater treatment facility. This network represents all of the connected households and businesses that flush and drain their wastewater into that wastewater treatment plant.<\/span><\/p>\n<\/div>\n

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<\/b>Why report COVID-19 infection\/trends occurring in the sewershed?<\/span>

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Comparing trends of reported cases within the sewershed to trends in wastewater can help understand the amount of COVID-19 in a community over time.<\/span><\/p>\n<\/div>\n

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<\/b>Where is wastewater surveillance happening in Virginia? Is my city participating in the Virginia Sentinel Monitoring Program?<\/span>

<\/b><\/p>\n

We are currently sampling wastewater from 25 sites in Virginia… You can check to see if your community is participating on the Sentinel Monitoring Map.<\/span><\/p>\n<\/div>\n

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<\/b>How is wastewater data being used to support the COVID-19 response?<\/span>

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Studies have shown that the wastewater viral load will increase about a week before there are increases in patient cases.\u00a0 That\u2019s because people with COVID-19 start shedding the virus within 2 to 3 days of becoming infected, even before they feel sick.\u00a0<\/span><\/p>\n<\/div>\n

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<\/b>What happens if wastewater surveillance shows an increase in COVID-19?<\/span>

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State and local public health officials review the data along with other COVID-19 metrics to determine the need for action, which may include:<\/span><\/p>\n