MADISON, Wis. (AP) — Every Wisconsin county had a high rate of COVID-19 infections on Thursday and intensive care units were at or near capacity in almost every hospital in the state, even though cases had been steadily dropping over the previous nine days.

Although the decline in cases is encouraging, it’s too early to say that Wisconsin has seen the worst of the latest surge caused by the highly contagious delta variant, said Dr. Ryan Westergaard, the state’s chief medical officer.

“I don’t think there’s enough data to say we reached a peak or we’ve hit the downslide,” Westergaard said. “We need to remain vigilant.”

Westergaard stressed the importance of getting vaccinated and for those who got the Pfizer vaccine and are eligible for a newly approved booster to receive that as well.

The Wisconsin Department of Health Services recommends a booster dose of Pfizer at least six months after receiving their second dose for people ages 65 and over; residents in long-term care and people ages 50-64 with certain underlying medical conditions including cancer and chronic lung disease.

Others who may get a booster include people ages 18–49 years with certain underlying medical conditions; people ages 18–64 years who are at increased risk for COVID-19 exposure and transmission because of their jobs, including teachers, grocery store workers and public transit employees.

For now, only those who received the Pfizer vaccine are eligible for booster shots. People who received the Johnson & Johnson or Moderna vaccines are not supposed to get them.

Westergaard also urged people to get their annual flu shot to help prevent even more patients requiring stays at hospitals that are near capacity because of COVID-19 cases.

As of Wednesday, the seven-day average of new cases was 2,416. That was down from the Sept. 20 high of 2,932 for the current surge but was still 745 more than the seven-day average of a month ago. Case rates among children, meanwhile, were at the same level as they were during the height of the pandemic last fall, Westergaard said.

Twenty-one Wisconsin counties were seeing critically high levels of new cases, with all other counties at high levels. At hospitals, 96% of ICU beds were in use and 97% of intermediate care beds were full, Westergaard said. That means many hospitals are at or near capacity or will be there soon, he said.