Wastewater virus levels rising, health officials urge boosters, tests, and masks

As of Monday, the amount of virus in local wastewater had jumped 3.1% over the past seven days and 99.9% over two weeks.

David L. Ryan/Globe Staff
Waste water coming into the Deer Island treatment plant is tested for traces of the virus that causes COVID-19

Boston health officials are urging residents to vaccinate, test, and mask indoors as the concentration of COVID-19 in local wastewater continues to rise.

As of Monday, the amount of virus in local wastewater had increased 3.1% over the past seven days and 99.9% over two weeks, the Boston Public Health Commission said in a Friday release. 

More on wastewater

“The elevated concentration of COVID-19 in our wastewater is very concerning,” Dr. Bisola Ojikutu, commissioner of public health and executive director of the Boston Public Health Commission, said in a statement. 

Wastewater monitoring can be an early indicator of COVID-19’s spread, according to the Centers for Disease Control and Prevention. Data from the Massachusetts Water Resources Authority — which tracks eastern Massachusetts wastewater at the Deer Island Treatment Plant — shows virus levels fluctuating following a steep spike that began in late September.


However, those numbers were still far lower than during the omicron surge at the start of this year. 

What are the latest numbers?

New COVID-19 cases in Boston decreased by 0.5% in the week leading up to Oct. 3, but were up 1.1% over two weeks, according to BPHC. That data does not include results from at-home tests, an increasingly popular testing option. 

Boston hospitals, meanwhile, had 170 new COVID-19-related hospital admissions this week. While the city’s hospitalization rate was stable over the past seven days, it represents a 13.7% increase over two weeks, BPHC noted. 

“Combined with flu season, increases in COVID-19-related hospitalizations will cause major strain on Boston’s health care system,” Ojikutu said. “It’s important we get ahead of this by getting boosted, obtaining a flu shot, wearing masks indoors, testing for COVID, and isolating if positive to help reduce transmission.”  

What can you do?

The commission is working with Boston hospitals and provider networks to ensure they are prepared for a scenario like the one Ojikutu described, according to its release. 

“Improving uptake of the new bivalent COVID-19 boosters, which provide the broadest protection and immunity against the original COVID-19 strain and the omicron variant, is critical to this goal,” BPHC said. 


The commission administered 783 COVID-19 vaccine doses last Saturday during a free vaccination clinic at White Stadium in Franklin Park. Today, 78.7% of Boston residents are fully vaccinated, according to BPHC. 

BPHC also advises other precautions, including testing before and after large gatherings, wearing masks indoors — especially in crowded places — and opting for outdoor activities as often as possible.


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