Wastewater data gap follow-up: an update from Biobot

Quite a few sites on the CDC NWSS dashboard are still not reporting recent data, but Biobot is working to bring them online.

Last week, I pointed out a data gap on the CDC’s National Wastewater Surveillance System (NWSS) dashboard: hundreds of sewershed sites on the dashboard have not been updated with recent data in weeks.

In this post, I hypothesized that the gap was likely a result of a shift for NWSS, as the CDC has switched from a contract with testing company LuminUltra to a contract with Biobot. In both cases, the outside company had been hired to conduct wastewater sampling and analysis for sites that don’t have capacity to do this themselves; as NWSS transitioned between testing providers, some sites were left without recent data.

This week, I’m excited to share an update on the situation, courtesy of Becca Malizia, Biobot’s science communication manager, who reached out after seeing last week’s post. Below, you’ll find more details on the recent data gaps and Biobot’s new relationship with the CDC.

Malizia confirmed that the transition between LuminUltra and Biobot has led to delays in wastewater data availability for some sites in the NWSS network. She pointed me to a footnote on the CDC dashboard, labeled “May 2022 Coverage Limitations”:

Beginning April 15, 2022, approximately 150 wastewater sites in 29 states began transitioning to a new wastewater testing provider. During this transition, these sites will not have recent data displayed and will be colored gray on the map. It will take several weeks for enough data to be collected to calculate the metrics displayed on this page. Results for these sites are expected to be available again between mid-May and June 2022.

Now, if the CDC was going for full transparency and ease of dashboard interpretation here, the agency should have placed this important note somewhere more obvious to the average user—not buried at the bottom of the page. But I’m glad to see this public information, including the estimate of when results for the transitioning sites will be available.

Biobot also acknowledged the data gap in a Tweet on May 19, explaining that the company has experienced issues in distributing testing kits to participating sites:

Further contributing to data delays, the sewershed sites for which Biobot is now in charge of sampling require a “minimum number of samples” before key metrics on the CDC NWSS dashboard can be calculated, Malizia said. The calculations for these metrics change from one lab to another, so Biobot needs to use data from its protocols rather than data from the prior LuminUltra contract.

“Sites in the process of switching over from the previous contract may have some lag until there is enough data to do the calculations for the CDC metrics,” Malizia wrote. She also pointed to several other reasons why a sewershed site might collect wastewater data, but not have its data appear on the CDC dashboard, such as: a sewershed serving under 3,000 people, a sewershed serving a specific institution (like a college campus), and a sewershed where local leaders have elected not to send data to the CDC.

Biobot has already onboarded more than 200 wastewater treatment plants, Malizia said; this includes sites that were previously included in the NWSS contract with LuminUltra, though a full list of those sites is not publicly available. By mid-July, Biobot aims to have 500 sites participating in its CDC program. The company works with state and local health departments to select wastewater sampling sites and coordinate with treatment plants.

Now, it’s important to note that, outside of its CDC NWSS contract, Biobot coordinates wastewater testing and analysis for hundreds of sewershed sites through a program called the Biobot Network. This program is a public service offering from Biobot: the company does testing and analysis at no cost to sewersheds. But Biobot also does not send individual, sewershed-level data back to the participants. “Rather, the data is aggregated at the county level on our public dashboard (biobot.io/data) for the benefit of policymakers and the general public,” Malizia explained.

(The free Biobot Network includes two sampling sites in Hillsborough, Florida which used to be paid Biobot customers in 2021, Malizia said, in comments responding to the Tampa Bay Times article I quoted last week. The final reports those sites received when they were paying customers were in August and October of last year. “Individual wastewater treatment plants can choose whether or not to share these reports with local government agencies,” Malizia said.) 

Before it became a CDC contractor, Biobot was not able to submit wastewater data to the agency. Only state government agencies have access to the CDC NWSS platform used for data reporting, Malizia said; the CDC has made an exception for Biobot under the new contract. To me, this helps explain why there’s not a lot of overlap between Biobot Network sites and CDC NWSS sites, as well as why some other wastewater sampling (done by universities, research institutions, etc.) does not appear on the CDC dashboard.

But, now that Biobot is a CDC contractor, will the company provide Biobot Network data to the agency? I asked Malizia this question, to which she responded:

The Biobot Network will remain separate from the NWSS, however sites enrolled for the CDC NWSS Program will also be given the option to opt into the Biobot dashboard.

In summary: Biobot is working hard to restore data from sites already in the CDC NWSS network and expand that network to more sites that don’t have capacity for wastewater sampling on their own. However, thanks to a combination of CDC bureaucracy and complex public and private data systems, it seems unlikely that we will get a singular dashboard including all wastewater testing sites in the country anytime soon.

Also, Biobot’s current contract is only for nine months. Are we going to see another round of data gaps next winter, if the CDC decides to switch wastewater testing companies again?