PORTLAND, Ore. (KOIN) – Oregon is ending 2024 with the state's highest pertussis case count in 74 years, prompting state health officials to encourage vaccines against the disease.

As of December 30, the Oregon Health Authority has reported 1,105 cases of pertussis -- also known as whooping cough -- in 2024, marking the highest number of cases since 1950, which saw 1,420 reported cases.

According to OHA, 2024's case count is an "extremely high" number considering the disease can be prevented by vaccine.

“The pertussis vaccine is a public health success story in terms of its effectiveness in reducing severe illness and deaths from the disease—particularly among infants,” said Dr. Paul Cieslak, medical director for communicable diseases and immunizations at OHA’s Public Health Division, in a press release issued Monday.

The warning from OHA comes as Oregon saw 44 whooping cough outbreaks in 2024. However, most of 2024's cases were individual or household-related and were not related to an outbreak, OHA noted.

Since 2003, eight Oregonians with pertussis have died, with five of those cases involving Oregonians who were under four months old, OHA said. Three adults with the disease have recently died, including one death in 2023 and two deaths in 2024.

The median age of the 2024 cases is 12, with over 7% of cases found in children less than a year old. Additionally, 80% of the cases are among those 18-years-old or younger and about half of the cases are up to date on pertussis vaccines, officials said.

Lane County has reported the highest number of whooping cough cases in 2024 with 315 cases followed by Multnomah County with 235 cases, Clackamas County with 135 cases, Washington County with 119 cases, and Marion County with 75 cases, according to OHA.

Even though Oregon has not surpassed the 1950 record for most cases in one year OHA is still concerned about the high number of cases.

Cieslak noted that whooping cough cases routinely reach the triple digits, except during the COVID-19 pandemic which saw lower case counts amid school closures and masking requirements. During this time, vaccination rates also slipped, he said.

“People were less motivated to get vaccinated against pertussis when there was less concern they would be exposed to the infection in the first place,” Cieslak added.

Because whooping cough activity is high in 2024, there are more chances for people to be exposed, Cieslak said, noting those who are unvaccinated or are too young to be vaccinated – such as infants – pose the highest risk for infection, with babies most likely to be hospitalized.

There are ways to protect vulnerable individuals, OHA says. This includes pregnant people getting the Tdap vaccine, which protects against tetanus, diphtheria, and pertussis at 27-36 weeks’ gestation to protect their baby.

OHA explained mothers will make antibodies and pass them to their babies, which will protect them from the moment at birth and is recommended during each pregnancy.

“In recent years, about two-thirds of pregnant Oregonians have been getting vaccinated during pregnancy,” Cieslak said. “However, only 11 of the mothers of the 80 infant cases this year had documentation of having gotten the recommended shot.”

Health officials said vaccination against whooping cough is routinely recommended for infants, children, adolescents, and adults. Children should receive the DTaP vaccine at ages two, four, six, and 15-18 months old and again at 4-years-old to kindergarten age. All people 10-years-old and older should receive a single dose of the Tdap vaccine.

“Additionally, when pertussis strikes a household in which an infant or pregnant person lives, we recommend all members of the household receive a course of antibiotics effective against Bordetella pertussis—typically, a five-day course of azithromycin,” Cieslak said.