As Dartmouth students flowed into residence halls last week in staggered waves for a return to on-campus learning, researchers at nearby Dartmouth-Hitchcock Medical Center were watching what flowed out of the dorms for clues of coronavirus infection.
The researchers are examining human waste flushed by students and others in the Twin States. They are looking for genetic material, RNA, from the virus that causes COVID-19.
Because somewhere between 40% and 65% of people shed the novel coronavirus in their stool as much as a week before they get any COVID-19 symptoms, and many people with the virus never develop any symptoms, a positive test from a wastewater sample could serve as an early warning sign of the presence of the virus.
As with many research projects developed in response to the COVID-19 pandemic, the wastewater researchers are “building the plane as we fly it,” said Jacqueline Hubbard, a D-H clinical chemist who is co-leading the effort with Dr. Isabella Martin, a D-H medical microbiologist, as well as Gregory Tsongalis, director of the Laboratory for Clinical Genomics and Advanced Technology at D-H.
The researchers wrote their first proposal for the project — now known as RECOVER, which stands for Regional COVID-19 Virus Evaluation in Recrement — in late May and are still working to refine the sampling and testing processes, Hubbard said. This is partly because of supply chain challenges regarding testing material, as well as the lack of a standard methodology for conducting such tests.
Hubbard, Martin and their team, whose wastewater work is primarily supported by a private anonymous donor, are using samples of wastewater collected from eight sites at Dartmouth as well as pilot sites in New Hampshire’s three most populous cities, Concord, Nashua and Manchester. Eventually, they plan to expand to a total of 10 municipalities and 20 total sites, including senior living communities such as Kendal at Hanover, as well as prisons in the Twin States. Samples are slated to be collected from each site twice a week.
Dartmouth is regularly testing students on campus for COVID-19, but the wastewater tests could be another tool college officials use to contain the virus’s spread, said Dr. Lisa Adams, an infectious disease specialist at D-H who is co-chair of Dartmouth’s COVID-19 task force. An early warning could be helpful in preventing an outbreak, such as those that have caused some colleges and universities around the country to send students home in recent weeks.
“The longer cases go undetected, that’s what allows unchecked, uncontrolled transmission,” Adams said. “Speed is of the essence here. Having that early signal is very exciting.”
While Adams was enthusiastic about the opportunity for the college to collaborate with D-H and to learn more about how wastewater could be used to monitor for the presence of COVID-19 in the community, she also said that Dartmouth hadn’t yet sorted out how information learned from the tests might be integrated into the college’s response to the pandemic.
It’s not yet clear what a positive test result might mean. Adams noted that someone who has previously tested positive for the virus may continue to shed the virus in their stool for several weeks after they are no longer infectious. So, should the college receive a positive wastewater result, school officials will need to do some work to determine if it is really a signal of a new infection.
“We are on the cutting edge,” she said.
If in fact one of the eight testing sites at Dartmouth, which include dorms and groups of dorms serving between 80 and 600 students, does get a positive result indicating a new infection, she said the college would reach out to the students in the buildings involved and encourage those who haven’t recently been tested to do so. Before results come back, the college could require those living in the buildings involved to quarantine in their rooms except for picking up meals and exercising alone.
Students are slated to be tested weekly, after initially being tested more frequently, Adams said. The wastewater results could help pinpoint where more testing might be needed in between the scheduled tests, she said.
“I hope we learn that this is an effective method that does provide early warning signs to achieve the ultimate goal that we’re all striving towards … (to) keep our community as healthy as possible,” she said.
D-H is among many institutions around the country who are evaluating how wastewater might be used to monitor for COVID-19. The Centers for Disease Control and Prevention last month launched the National Wastewater Surveillance System, aimed at gathering wastewater testing data from around the country to aid public health officials in their response to the pandemic.
Some institutions, such as the University of Arizona, have reported early success in using wastewater testing to catch cases and halt outbreaks. After a wastewater sample comes back positive, the people using the facilities where the sample was taken have to be tested to confirm infection. In the Arizona case, two asymptomatic students living in the dorm where the positive wastewater sample came from later tested positive and were then isolated from others.
The D-H researchers also suggested that wastewater testing could eventually be used to reduce the human diagnostic testing being done for screening purposes in at-risk communities, such as at nursing homes where staff are screened every 10 days.
But, scientists and public health officials caution that the methods for sampling and testing wastewater for the presence of COVID-19 have yet to be standardized and can’t replace testing individuals for the disease.
“Everybody is circumspect to use this to inform public health policy,” said Sharon McMillin, environmental program administrator for the New Hampshire Department of Environmental Services.
McMillin pointed to the lack of a “certified test method” and the fact that researchers are trying to develop one in the midst of a pandemic as some of the challenges to using wastewater testing as a public health surveillance tool. Further complicating matters is the fact that roughly 60% of people in New Hampshire use septic systems, not municipal wastewater. In addition, flushes from visitors and workers can make the data harder to interpret.
“It’s very difficult to say who’s on the sewer and what’s going on,” she said. “Who’s there on a given day? Did you catch the flush of that infected person or not?”
But, McMillin said, DES has been working with the University of New Hampshire to collect municipal wastewater samples for a separate study that is ongoing there and she’s hopeful that project, and the work at D-H and elsewhere, will mean that wastewater could be used as a surveillance tool down the road.
Lebanon Deputy Director of Public Works Jay Cairelli said the city was happy to work with the D-H researchers to establish sampling sites near Sachem Village, housing owned by Dartmouth in Lebanon, and at the city’s wastewater treatment plant. He’s hopeful the project will “give people an early warning” so they can “take necessary precautions if we choose to,” he said.
Kendal at Hanover, a retirement community off Route 10 that has not yet had a reported case of COVID-19, also is slated to be a sampling site for the D-H project, said Jason Smith, Kendal’s director of health care innovations.
“This is a great way of providing identification without invasive testing,” Smith said. “But, I look forward to more research on this and seeing how effective this really is.”
Nora Doyle-Burr can be reached at ndoyleburr@vnews.com or 603-727-3213.
