Wastewater testing for viruses increased during the COVID pandemic. Alaska health officials are working to expand those efforts.

Feb. 24—Each Tuesday, a team of scientists at the University of Alaska Anchorage spend much of their day carefully extracting and testing microscopic strands of ribonucleic acid found in a jug of wastewater collected from a city sewage facility. They do this to detect levels of SARS-CoV-2, the virus that causes COVID-19.

The process — which UAA professor Brandon Briggs' lab has been involved with since early in the pandemic — is part of a growing public health effort in Alaska to use wastewater as a way to track not just COVID but a range of other viruses and diseases, including tuberculosis, RSV, flu, monkeypox and noroviruses.

"I see a lot of utility in this," said Clayton Weingartner, a program manager with the state health department.

Wastewater testing can be used as an early warning tool: People often start to shed viruses before they show symptoms or start to feel sick, he said.

And because most Alaskans are now using at-home rapid tests to check for COVID-19, if they're testing at all, wastewater monitoring has also become one of the best ways to measure the spread of the virus.

"People are still getting sick, but they're not going in and actually getting tested," said Briggs. "So the city and the state don't really know what the true incident rate of that particular pathogen is. And it's only once we have that type of information, we can get a better idea of what's actually happening across that community, rather than just relying on a handful of people."

Early in January, wastewater collection data from Anchorage showed a significant spike in COVID-19 — it has since declined — that Dr. Louisa Castrodale, an epidemiologist with Alaska's state health department, said matched the trend data they were seeing at the time.

And while the data collected through wastewater cannot be manipulated to measure case numbers or incidence rates, since everyone sheds different amounts of virus when they're sick, the value of the data is that it can show early trends, Briggs said.

Scientists and Alaska health officials say they're currently building up the state's ability to use wastewater testing to track the spread of viruses.

Using community wastewater to monitor for diseases isn't new. Scientists have been looking for clues in sewage since the 1800s. In the 1940s, researchers used wastewater testing to monitor cities with polio outbreaks.

During the COVID-19 pandemic, many states, including Alaska, received federal funding from the Centers for Disease Control and Prevention to test wastewater for the virus. Now, the state is looking into finding ways to expand those efforts in more rural parts of the state and to track other diseases.

The state recently hired a wastewater informaticist to help manage its efforts.

"It's been around for a bit," Briggs said. "But I think the pandemic really highlighted the importance and the ability to get key information out so we can start seeing things move before they actually become a problem."

Like following a recipe

On a recent Tuesday in a sunlight-filled room on an upper level of the ConocoPhillips Integrated Science Building at UAA, three scientists — lab manager Eric Henderson, and researchers Nate Beck and Victoria Triglia — embarked on a daylong process of testing wastewater. It involved many steps and lots of waiting.

"Kind of like cooking, it's just following a recipe," said Henderson.

The process of testing wastewater for SARS-CoV-2 is similar to what happens in a laboratory after someone gets their nose swabbed and tested with a PCR test, Briggs said.

First, the water is collected in the morning at the John M. Asplund Wastewater Treatment Plant near Point Woronzof. Then, the scientists pour the bottle of wastewater into a cooled centrifuge to separate out the liquids from the solids.

The solids — which eventually are spun into tiny pellets that weigh about a gram — contain the most concentrated amounts of RNA and DNA, which make them the most useful for testing, Triglia explained.

Then, the researchers extract strands of RNA from the pellets, which they use to measure the different levels of virus in the sample.

These scientists have been perfecting their testing efforts for the past several years in order to get increasingly accurate results, Briggs said.

They've also gotten much more efficient — at the beginning of the pandemic, the testing process took about three or four days, and now is done in under 24 hours, Briggs said.

UAA's efforts are duplicated by Verily, a corporation that also tests Anchorage wastewater samples in a Lower 48 laboratory. Verily's data is reflected on the online wastewater dashboard. Briggs said the benefit of in-state processing is even faster turnaround times.

"We're trying to make sure that we have the capacity here in Alaska, and that we can turn this around a lot faster because we're not shipping it down to the Lower 48 and waiting two or three days for the results to get back," he said.

Moves to expand testing efforts in Alaska

At UAA, Briggs said his lab is in the process of expanding: They've been working on sequencing efforts to detect other kinds of viruses, and will be publishing their weekly data online soon.

He said his hope is to see the city and state start to use this data to inform public health decisions and guidance, and aid decisions about where to allocate resources.

"Alaska's main focus right now is building capacity to do (wastewater surveillance) on our own here in the state," said Weingartner. The state has plans to expand additional testing sites in the Mat-Su and Fairbanks later this year — and to expand beyond COVID-19 soon, too, he said.

He said the state in particular is working on expanding to more rural parts of the state, where wastewater testing can be particularly challenging due to a lack of infrastructure and laboratory resources.

The state is also trying to figure out the best way to use the data they collect.

"We're working on putting that data to action," he said. "If we see a significant spike, we would respond."