With Hopkinton currently carrying a medium risk designation for COVID-19, Hopkinton Health Director Shaun McAuliffe is urging residents not to let their guard down.

He said attendance at the department’s most recent vaccine clinics was “terrible,” leading to concerns that the town could run the risk of another surge similar to the spring.

Two new variants, BA.2.12.1 and BA.5, have been detected in town, which is no surprise, as they account for the overwhelming majority of cases in the country.

“Everything I’ve read over the last couple of days suggests that [these variants are] extremely transmissible, but they’re just not as virulent,” he said, noting that a single elevator trip could be enough exposure to convey the illness.

The Massachusetts Department of Public Health has reported 53 cases in town over the last two weeks, but McAuliffe believes the actual number to be much higher, likely 300-500 cases over the past month.

For those considering waiting for an updated booster that would include protection against the most recently detected variants — expected to be available at some point this fall — McAuliffe suggests getting a shot now.

“It does make sense [to get the current booster],” he said. “If nothing else it’s just going to blunt the severity of the illness that you get. I just got my second booster when I got COVID [in April]. The argument is, with the doctors that I’ve talked to, I may have had a harsher case of COVID had I not been as vaccinated.”

McAuliffe referenced studies that indicated damage to sinus tissue, lung tissue, throat tissue and kidneys in COVID patients, and he said the booster should offer some protection.

“You might still get COVID, but the boosters and the vaccines in general will protect against that damage,” he said.

McAuliffe said the town had such little interest in the booster for ages 5-11 that his department gave most of its supply to a local pediatrician, keeping enough for individuals who are uninsured. He added that additional supply is expected next month. Then there should be updated vaccines that include a flu vaccine in the fall, and he expects that will be more popular.

But again, McAuliffe said, it’s not a great strategy to wait.

“It’s better to just get one more [vaccine] in you,” he said, indicating he expects approval for a third or even fourth booster sooner rather than later.