The increase makes sense for this time of year, as people spend more time indoors in air-conditioned spaces or settle back into their fall routines, experts said. Residents are returning from vacation, and students are returning to school, said Andrew Lover, associate professor of epidemiology at the University of Massachusetts Amherst.
“It doesn’t look particularly worrisome. It’s kind of expected,” Lover said.
Over the last few years, the uptick has peaked in late August and lasted until Labor Day, he said.
So far, Massachusetts has not been impacted as heavily as other states, including Texas, Nevada, and Utah, which have reached “very high” levels of waste water, according to CDC data from Aug. 3 to Aug. 9.
Infectious disease experts are keeping a close eye on the now dominant variant, XFG or “Stratus”, which was first identified in Southeast Asia in January.
According to CDC data, the XFG variant accounts for 65 percent of virus samples in waste water as of Aug. 9.
It’s hard to tell the extent to which Stratus is affecting Massachusetts, because sequencing — the process that determines the genetic makeup of a virus — has “dropped off” in a lot of places, Lover said.
Stratus causes similar symptoms to other COVID-19 variants, including fever or chills, cough, shortness of breath, sore throat, and loss of taste or smell.
The updated COVID vaccines that the Food and Drug Administration approved earlier this year should offer “some pretty decent protection” against Stratus, Lover said. The World Health Organization said “currently approved COVID-19 vaccines are expected to remain effective” against this variant, according to a June report.
Unlike previous years, however, the Centers for Disease Control and Prevention’s vaccine advisory committee has yet to issue recommendations for who should receive booster shots this fall.
“One worry, right now, is that vaccine uptake may be suboptimal relative to prior years,” Lover said. “We’ll have to see what comes out in the next few weeks.”
The Food and Drug Administration is considering limiting the COVID-19 vaccine to adults over the age of 65 and people who are at high risk.
As long as the FDA approves the drug, clinicians can still prescribe it to people outside those limitations, said Daniel Kuritzkes, the chief of the division of Infectious Diseases at Brigham and Women’s Hospital.
“If the vaccine is approved, any physician can prescribe it to a patient who they think might benefit from the vaccine,” Kuritzkes said.
But the FDA is also weighing whether to revoke authorization for Pfizer’s COVID vaccine for children under the age of 5. If the FDA does that, physicians would have “no discretion” to provide the vaccine for people who fall outside those restrictions, because authorizations are more restrictive than approvals, according to Kuritzkes. Pfizer is the only COVID vaccine available to that age group, so if authorization is revoked, kids younger than 5 will not have an officially approved option.
On Tuesday, the American Academy of Pediatrics, diverging from the federal government, strongly recommended COVID-19 shots for children ages 6 months to 2 years. The group also advised that older children should have access to the vaccines.
Despite the uncertainty this fall, Dr. Sabrina Assoumou, an infectious disease specialist at Boston Medical Center, encouraged patients to stay up-to-date with their vaccinations. “Vaccines protect against severe disease, hospitalization, and death,” she said.
Another way to lower the risk of infection is to move gatherings outside, if the option is available, because ventilation can decrease the risk of transmission, she said.
If you are at risk for severe disease and develop COVID, contact your health professional, she said.
“If you have symptoms, get tested — so we can break that chain of transmission,” Assoumou said.
Assoumou encouraged patients to listen to local and state public health agencies, as well as professional medical societies, like the Infectious Diseases Society of America, of which she is a member. The society is working with the Vaccine Integrity Project to create guidance on COVID-19 immunization, and on Tuesday the group released a report detailing key findings on the effectiveness of COVID-19 vaccines.
But ultimately, doctors like Assoumou are waiting to see what the federal government will do.
“At this point, it’s most helpful to wait to see what happens, so that we can make recommendations [to the] public,” Assoumou said.
Jessica Ma can be reached at jessica.ma@globe.com.
