10/1/20 COVID-19 Brief: Go with the Flow – Testing Sewage to Inform Targeted COVID-19 Testing

Testing of sewage isn’t new to public health, and it has been used by municipalities in the US and around the world since early in the pandemic. Now the idea of using sewage to prevent outbreaks at universities and within workplaces is gaining the attention it deserves.

A Message on COVID-19 from WorkSTEPS Chief Medical Officer Dr. Ben Hoffman

Go with the Flow – Testing Sewage to Inform Targeted COVID-19 Testing

Meet Tom

Tom manages one of several manufacturing facilities for his company. As far as COVID-19 goes, the past few weeks have been good. There have been no outbreaks, and – to his knowledge – none of the employees or contractors reporting to work today is sick with COVID-19.

“To his knowledge…” That’s the problem.

Tom doesn’t know about Phil in maintenance who is asymptomatically sick and doing a walk-through of the packaging line right now. He also doesn’t know about Sarah who attended a family wedding over the weekend, caught the virus and will wake up in two days with a 102-degree fever. At this moment, Sarah is on break, she’s taken off her mask to eat a bagel, swapping stories between bites and laughing with her coworkers.

Tom could increase his knowledge if his plant implemented screening tests, testing all employees and contractors every three or five days so that he could know when someone was sick. But until a fast, accurate and affordable test is available, that sort of testing is too costly, time-consuming and logistically complex. So, Tom does the best he can with the knowledge he has.

Tom’s situation may sound familiar. We get a lot of calls from people like Tom.

The Answer May Be Flowing Under Tom’s/Your Feet

Like many diseases, COVID-19 leaves its signature in our poop. In fact, Dr. Ian Pepper, an environmental science professor at the University of Arizona, says that sewage sampling can pick up a single positive case in a group of 10,000.

Pepper’s work at the University of Arizona drew attention recently when sewage testing prevented an outbreak on campus. His team tests sewage sludge flowing from dormitories on campus, and recently detected COVID-19 at the collection point for one of them. That result triggered targeted testing of over 300 residents. Two asymptomatic students were quickly identified, quarantined, and contact tracing and testing of close contacts was conducted to contain the outbreak.

Testing of sewage isn’t new to public health, and it has been used by municipalities in the US and around the world since early in the pandemic. Now the idea of using sewage to prevent outbreaks at universities and within workplaces is gaining the attention it deserves.

For many companies, sewage testing can be an efficient and effective way to do surveillance for the presence of COVID-19 at the worksite. The process is pretty straight-forward:

  • 1. Identify the place (or places) to collect samples: The wastewater line flowing from a facility is a good place to start, but if a facility is large enough, look for opportunities to sample sewage in different areas of the building. Decisions on where to sample should be informed by an understanding of how much people move among places in a building or buildings on a campus. Vendors that supply testing kits will typically provide helpful instructions.
  • 2. Establish a baseline: Pathogens remain in sewage lines for some time, so an initial test may detect COVID-19, but that reading won’t provide a reliable picture of current cases or risk.
  • 3. Watch for and Act on Trends: If the concentration of COVID-19 detected in wastewater remain level or go down, no action is necessary. Rising concentrations of COVID-19 indicate an uptick in infection, and the population using toilet facilities should then be targeted for diagnostic testing. Those who test positive should then be isolated and interviewed so that contact tracing can be conducted.

The advantages of testing sewage are pretty obvious. It provides an efficient and effective means of COVID-19 surveillance, enabling targeted testing of employees and contractors only when there is reason to believe that someone is infected.  

There are a couple of drawbacks. Multi-tenant office buildings could complicate follow-up on testing of sewage, and while even toddlers understand that Everyone Poops, some people don’t poop at work.

If you’ve not yet requested a copy of our COVID-19 Testing Guidance, you can click here to do so. And, if your company would like help thinking about how sewage testing can fit into your testing strategy, let us know. We’re here to help.

Ben Hoffman, MD, MPH
Chief Medical Officer, WorkSTEPS

For more from Dr. Hoffman, connect with him on LinkedIn.

WorkSTEPS is hosting a series of informational webinars, each focused on a unique Covid-19 business challenge. Click here for more information and to register for the following:


Area Reported Cases Deaths Recovered
Global 34,392,996 1,022,284 25,584,885
United States 7,480,307 212,325 4,722,657


Global: On Monday, global COVID-19 deaths passed the 1 million mark, just 9 months into the pandemic. The US is leading in total deaths and infections. Brazil has the second leading death toll. Currently, in Brazil cases are on the rise again in Manaus city (the Amazon region’s largest city). This rise is dashing hopes that herd immunity contributed to an earlier drop in cases. Manaus added restrictions to deal with the surge. India is third in death toll and is leading with world with *new daily cases, which are in the 80,000s. Mexico and the UK rank at 4th and 5th.

National: Across the United States, at least 200,000 more people have died than usual since March. In terms of fatalities, the Northeast still makes up nearly half of all excess deaths, though numbers in the region have drastically declined since April. As the pandemic spread, the number of hot spots expanded, and so has the number of excess deaths across other parts of the country. As we come into cooler weather, the area seeing the biggest surge in new cases is the Midwest. The number of tests coming back positive is topping 25% in several Midwest states, with North Dakota leading at 30% and South Dakota  at 26%. Minnesota and Montana are averaging 7% of tests coming back positive.

Scientists Discover Genetic and Immunologic Underpinnings of Some Cases of Severe COVID-19: New findings by scientists at the National Institutes of Health and their collaborators help explain why some people with COVID-19 develop severe disease. The findings also may provide the first molecular explanation for why more men than women die from COVID-19. The researchers found that more than 10% of people who develop severe COVID-19 have misguided antibodies―autoantibodies―that attack the immune system rather than the virus that causes the disease. Another 3.5% or more of people who develop severe COVID-19 carry a specific kind of genetic mutation that impacts immunity.

NIH Panel finds data on convalescent plasma inconclusive: The NIH COVID-19 Treatment Guidelines Panel  found data was inconclusive to recommend for or against convalescent plasma for treating COVID-19. The review evaluated data used to support the EUA, including a cohort of 4,330 patients from the Broad Institute and data from 3,082 patients from Mayo Clinic. The Broad Institute data compared patients younger than 80 and found a difference in 7-day mortality for patients receiving high- and low-titer convalescent plasma of 6.3% versus 11.3%. The Mayo Clinic data evaluated patient outcomes for three different antibody levels, finding a statistically insignificant 4.7-percentage-point difference in 30-day mortality rate between high- and low-titer groups 24.7% vs 29.1%.

Regeneron’s COVID-19 antibody may help non-hospitalized patients recover faster, early data show:  A high dose of the company’s antibody cocktail, REGN-COV2, led levels of the virus to decrease more quickly in infected, non-hospitalized patients, potentially indicating the treatment may help them get better, Regeneron reported Tuesday via press release. Full results will be published at a later date.

Susceptibility in Children & Adolescents: A systematic review and meta-analysis published in JAMA: Pediatrics describes findings from 32 contact tracing studies and population screening studies to compare susceptibility to SARS-CoV-2 infection among children and adolescents to susceptibility among adults. The researchers—from Australia, the Netherlands, and the UK—evaluated studies representing 41,640 children and 268,945 adults. They determined that individuals under 20 years old had 44% lower odds of infection compared to older adults, a statistically significant difference. Notably, they determined that this association appeared to be largely attributable to younger children—under the age of 10-14 years—and that adolescents appeared to have similar infection risk as adults.

Mitigation / Suppression:

WHO and partners deploy tiny rapid test this week: The WHO and partners announced a program to supply low- and middle-income countries with 120 million rapid tests for SARS-CoV-2 over the next 6 months. The deal, part of the WHO-led ACT Accelerator, will deploy 120 million of these tests across 133 countries. Countries can start ordering their tests this week.

The rapid tests cost less than $5 apiece and provide reliable results in 15 to 30 minutes at a lower price point without specialized staff or medical equipment. The goal is to enable the expansion of testing especially for low to middle income nations with access to healthcare issues. Current tests can take days to come back.

U.S. to send 100 million rapid COVID-19 tests to states and territories in effort to reopen schools: The U.S. just announced that it would be shipping millions of rapid COVID-19 tests to states across the country in an effort to get kids back in school. Around 6.5 million tests from Abbott Laboratories will be sent this week, with a total of 100 million to be shipped to states and U.S. territories in the coming weeks. This rapid test, which does not need any specialized equipment, is intended to help teachers know quickly whether they or someone in their class is sick and is also intended to help parents determine whether to keep their child at home or send them to school.

The US Military’s Latest Wearables Can Detect Illness Two Days Before You Get Sick: Some troops in the US military are wearing a watch and ring kit that can alert them and their command if they’re going to get sick in the next day or two. It’s part of a new system that the Defense Innovation Unit, or DIU, has built with Philips Healthcare and the Defense Threat Reduction Agency, or DTRA. The watch and ring — by Garmin and Oura, respectively — are commercially available; they detect subtle biometric indicators, like slight changes in skin temperature. But a new algorithm, trained on Philips’ massive cache of patient bedside data, can analyze the data and predict whether the wearer will soon become ill from any of a wide variety of diseases, including COVID-19. Called Rapid Analysis of Threat Exposure, or RATE, the system can’t tell you exactly what you have, but can tell you the likelihood, on a scale of 1 to 100, that a sick day is ahead.

Rejection faced by many contract tracers: Suspicion over spam and phishing calls has thwarted coronavirus contact-tracing efforts nationwide. Elected officials are pleading with citizens to pick up their phones. The rejection faced by many contact tracers has led state health departments to find alternative ways to reach out to people who were possibly infected: In Louisiana, people not reached by phone received letters in the mail. In the D.C. calls appear on caller-ID as “DC COVID 19 Team”.  But even with a clear caller ID, some are wary, leading to Dept. of Health (DPH) home visits. Philadelphia’s DPH health started sending text messages to people who test positive prior contact tracers call them. The texts advise them to expect a call from DPH and the phone number the call will come from.

FDA Authorizes First Point-of-Care Antibody Test for COVID-19: The US Food and Drug Administration issued an emergency use authorization for the first serology (antibody) point-of-care (POC) test for COVID-19. The Assure COVID-19 IgG/IgM Rapid Test Device was first authorized for emergency use by certain labs in July 2020 to help identify individuals with antibodies to SARS-CoV-2, indicating recent or prior COVID-19 infection. Today, that EUA is being reissued to authorize the test for POC use using fingerstick blood samples. This authorization means that fingerstick blood samples can now be tested in POC settings like doctor’s offices, hospitals, urgent care centers and emergency rooms rather than having to be sent to a central lab for testing.


Impact of the coronavirus on American households: Researchers published a new poll reviewing financial toll on Americans by the coronavirus. In the survey of 3,500 respondents, conducted from Jul 1 - Aug 3, 46% said they faced serious financial problems during the pandemic. That number jumped to 63% in households with a member who contracted COVID-19. About 21% reported serious problems paying credit card bills and other debt, and 19% reported having difficulty paying their housing.

A Layperson’s Guide to How — and When — a COVID-19 Vaccine Could Be Authorized (STAT News): In a U.S. pandemic response dominated by missteps, the effort to develop vaccines to prevent COVID-19 has so far been a triumph. Vaccines against the coronavirus that causes the disease are now racing through giant clinical trials as a result. Here, then, is a rundown of the science that goes into the decision-making process, what it tells us about when results could realistically be available, and when vaccines could start to be administered. This story is based on interviews as well as on documents the drug makers have released detailing their clinical trial plans.

Lawmakers Urge Wastewater-based Epidemiology COVID-19 Testing: A group of legislators recently encouraged the Centers for Disease Control and Prevention to invest federal funding in wastewater-based epidemiology (WBE) with an eye toward low-cost, effective COVID-19 testing. Rep. TJ Cox (D-CA) recently joined 11 colleagues in forwarding correspondence to the CDC regarding the matter while also requesting the CDC provide information on federal plans to implement a nationwide COVID-19 wastewater surveillance program. (Homeland Preparedness News, 9/23/2020)

The Work From Home WorkSTEPS Medical Team:

Ben Hoffman, MD, MPH
Chief Medical Officer

Tony Nigliazzo, MD
Medical Director

Loraine Kanyare, MSN, MPH, RN
Director of Case Management

Robert L. Levitin, MD
Physician Consultant

Lynda Phillips, LVN
Nurse Case Manager

Codey Church, LVN
Nurse Case Manager

Kerry Womack, LVN
Nurse Case Manager

Chuck Reynolds
Strategic Communications Consultant

This Guidance (“Guidance”) is provided for informational and educational purposes only. It is not intended as Legal Advice or Medical Advice. Adherence to any recommendations included in this Guidance will not ensure successful diagnosis or treatment in every situation. Furthermore, the recommendations contained in this Guidance should not be interpreted as setting a standard of care or be deemed inclusive of all proper methods of care nor exclusive of other methods of care reasonably directed to obtaining the same results. The ultimate judgment regarding the propriety of any specific therapy must be made by the physician and the patient in light of all the circumstances presented by the individual patient, and the known variability and biological behavior of the medical condition. Similarly, this Guidance is based on current advice, comments, and guidance from the EEOC, CDC and the CMS made publicly available. The ultimate judgement regarding the propriety of any specific employment action must be made by the company and attorney in light of all of the circumstances presented by the company, state and federal rules existing at the time and the then current state of the National Pandemic. This Guidance and its conclusions and recommendations reflect the best available information at the time the Guidance was prepared. The results of future studies or changes in rules, regulations or laws may require revisions to the recommendations in this Guidance to reflect new data. WorkSTEPS does not warrant the accuracy or completeness of the Guidance and assumes no responsibility for any injury or damage to persons or property arising out of or related to any use of this Guidance or for any errors or omissions.

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Newsletter written by WorkSTEPS CMO Dr. Ben Hoffman and WorkSTEPS’ expert medical team.