As the "stealth" BA.2 omicron variant becomes more prevalent in New England, the latest wastewater data shows another modest uptick in COVID-19 levels throughout Boston.
This data is prompting new concerns about what the wastewater levels mean for the weeks ahead in terms of a possible COVID spike.
Top Boston doctors spoke to NBC10 Boston during our weekly "COVID Q&A" session about the rise in COVID levels in the wastewater data. The doctors said the future remains unclear.
Dr. Shira Doron, a hospital epidemiologist at Tufts Medical Center, said the similarities between the BA.1 variant and the BA.2 variant make it hard to interpret the wastewater data.
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"If people with BA.2 have more virus, will you see more virus in the wastewater even in the absence of an increase in cases?" Doron said. "We've always said you can only look at wastewater data as it trends within a specific variant because there may be different viral loads associated with other variants, so this period where we are partly BA.1 and partly BA.2 is going to be a confusing time in terms of predictions."
Brigham and Women's Hospital's Chief of Infectious Disease Dr. Daniel Kuritzkes agreed with his colleague, but said he is concerned about the uptick.
"I agree with the caution," he said. "I would make the point that if precisely the same number of people were infected with BA.2 as were with BA.1 and you had triple the amount of virus in people that had BA.2 and the numbers aren't going down that is not a good thing."
Kuritzkes added that "The fact that the original omicron spike has declined doesn't mean that it is the last spike."
The BA.2 variant currently accounts for over 70% of COVID cases in New England. Health officials are still monitoring this variant for any possible spike or bump in cases or hospitalizations.
Boston Medical Center's Dr. Sabrina Assoumou said as the wastewater data rises, the message should be for people to continue to get vaccinated.
"The one thing I would add is that even though the immune evasion is very similar between the two subvariants, this is an opportunity for us to emphasize the importance of boosting," she said. "We don't have as many people boosted in the state or in the country as we would want to be prepared for a possible increase in cases."