Whooping Cough Continues to Spread Across Wyoming, Health Officials Say

Health officials say whooping cough cases continue to spread across Wyoming, with several counties reporting infections so far this year.

The Wyoming Department of Health said it remains concerned about the ongoing spread of pertussis, more commonly known as whooping cough. According to state data, 26 confirmed cases have been reported in Wyoming in 2026 so far. Roughly two-thirds of those cases are in Fremont County, though the illness has also been identified in other counties around the state.

Health officials say the current situation follows a significant increase last year. Wyoming reported 148 cases of whooping cough in 2025 — the highest number recorded in the state since 1951.

State epidemiologist Kaylyn Friesen said the real number of cases is likely higher because some infections are never formally diagnosed or reported.

Whooping cough often begins with symptoms that resemble a common cold, including a runny nose, mild fever, and a light cough. After about one to two weeks, the illness can develop into severe coughing fits, sometimes producing the “whooping” sound the disease is named for.

The illness can be especially dangerous for infants.

According to Alexia Harrist, the state health officer with the Wyoming Department of Health, about one-third of babies younger than one year old who contract pertussis require hospitalization. In some cases, the disease can be life-threatening for very young children.

“Infants are simply more vulnerable and don’t yet have all the protection pertussis vaccines offer,” Harrist said.

Health officials say people who develop symptoms consistent with pertussis should consider contacting a medical professional, since antibiotics can help treat the infection and limit its spread if caught early.

Doctors also note that vaccines and booster shots are available for children, teens, and adults. Officials say people who spend time around newborns — such as parents, grandparents, and caregivers — may want to talk with their healthcare provider about whether they are up to date.

More information about whooping cough symptoms, prevention, and treatment is available from the Wyoming Department of Health.