The state on Wednesday reported 907 new known cases of COVID-19 as it passed another threshold in the fight against the disease: More than 3 million Oregonians have received at least one dose of COVID-19 vaccine, officials said.

That’s 70% of the population at least partially inoculated since the state began administering the first shots one year ago. But state officials noted that much more work needs to be done, with about 64% of residents fully vaccinated and 21% vaccinated with a booster or extra dose.

Boosters are now more important than ever, with data showing two shots of Pfizer-BioNTech vaccine are 33% effective against infection from the fast-spreading omicron variant, compared to about 80% against delta. But epidemiologists believe boosters dramatically increase the body’s defenses against omicron.

Health experts also were urging parents to vaccinate their young children, ages 5 to 11, who became eligible for shots about six weeks ago. Only 27% of kids in this age group have received at least one dose.

“I am a huge proponent of vaccinations for kids and adults,” said Dr. Katie Sharff, Infectious Disease Specialist with Kaiser Permanente, in a written statement. “Recent studies have demonstrated that children who receive the pediatric-size vaccine are much less likely to have symptomatic infection or become seriously ill with COVID-19.”

Where the new cases are by county: Baker (3), Benton (8), Clackamas (63), Clatsop (25), Columbia (5), Coos (23), Crook (12), Curry (7), Deschutes (39), Douglas (51), Gilliam (3), Grant (12), Harney (3), Hood River (5), Jackson (63), Jefferson (5), Josephine (36), Klamath (18), Lake (2), Lane (68), Lincoln (8), Linn (45), Malheur (4), Marion (90), Morrow (3), Multnomah (128), Polk (28), Tillamook (13), Umatilla (16), Union (2), Wasco (2), Washington (87) and Yamhill (30).

Deaths: The state reported 39 new COVID-19 deaths, but no information about ages or locations of those who died. The state said it’ll release that information later.

Hospitalizations: 380 people with confirmed cases of COVID-19 are hospitalized, two fewer than Tuesday. That number includes 94 people in intensive care units, three fewer than the previous day.

Vaccines: The state reported 3,851 people receiving first shots since Tuesday.

Since it began: Oregon has reported 403,329 confirmed or presumed infections and 5,508 deaths, among the lowest per capita numbers in the nation. To date, the state has reported 6,446,469 vaccine doses administered, fully vaccinating 2,731,603 people and partially vaccinating 270,999 people.

— Aimee Green; agreen@oregonian.com; @o_aimee