Whooping cough cases continued to climb across northwest Montana Friday.
The Missoula City-County Health Department had logged 119 cases of the respiratory ailment between mid-April and Friday afternoon. It also revised its guidelines for excluding individuals with the infection.
“We are changing, revising our control strategy as the outbreak changes,” said City-County Health Officer Ellen Leahy.
Pertussis, better known as whooping cough, causes violent coughing fits and can be fatal to babies. The outbreak that’s hit Missoula County in recent months has been particularly hard.
Hatton Littman, communications director for Missoula County Public Schools, said that MCPS had 76 confirmed cases, and had screened nearly 2,000 individuals as of Friday afternoon. She said earlier reports of pertussis at Meadow Hill Middle School and Willard Alternative High School turned out to be false positives.
The City-County Health Department’s latest guidelines, issued Friday, state that any student, faculty or staff member with a confirmed pertussis case must be excluded from their school or day care until they complete five days of antibiotic treatment or until 21 days elapse from the start of symptoms.
In addition, if schools refer students to a health care provider for pertussis symptoms, they must receive documentation of either a negative pertussis test, testing not being warranted, or five days of antibiotic treatment before re-admitting them.
Flathead County has documented 132 cases since the start of its current outbreak, said Lisa Dennison, infectious diseases supervisor at the Flathead City-County Health Department.
“We started noticing a significant uptick in cases beginning in October 2018,” she said, explaining that the drumbeat of new cases had slowed to just one in April, but increased to eight this month. The cases have been concentrated among adolescents in Whitefish and Columbia Falls, she said.
Dennison added that the area’s last major outbreak had been in 2012-2013. “Pertussis is one of those illnesses that’s cyclical, so it’s not uncommon to see an outbreak occur every three to five years,” she said. The Flathead City-County Health Department advises against anyone with pertussis being in public until they complete their entire course of antibiotics.
Lake County has seen 13 cases since the start of its outbreak, said Leigh Estvold, a nurse with its public health department. Of those, she said, one had been in St. Ignatius High School and one in Arlee Elementary. The county’s relatively low numbers haven’t yet warranted exclusion guidelines, she said, “but if the outbreak grows we could potentially exclude students who haven’t been immunized.”
Visit the U.S. Centers for Disease Control website, cdc.gov/pertussis/index.html, for more information on pertussis and immunization recommendations.