With recently increased cases of pertussis (whooping cough) across the state, including a current outbreak in Sheridan County, the Wyoming Department of Health (WDH) is encouraging awareness of the disease.

At least 10 Sheridan County pertussis cases have been reported to WDH over the past couple of weeks with additional recent cases in Campbell, Johnson and Lincoln counties, according to a department release. 

“That brings us to 18 reported cases so far this year and we’re only in the year’s second month,” said Clay Van Houten, infectious disease epidemiology unit manager with WDH.

Van Houten noted pertussis activity went up in 2024 significantly with 19 total confirmed cases. There were no reported pertussis cases in 2023 and two in 2022. Actual case numbers in any year are likely higher because many illnesses are not recognized as pertussis and others may not be reported. The department sent a December 2024 advisory to Wyoming health care providers noting increased pertussis activity.

“Any surge in pertussis activity is something we watch with concern because it can be so tough on infants,” Van Houten said. More than half of infants less than 1 year of age who become ill with pertussis must be hospitalized; in some cases, it can be deadly.

“Thankfully, we have not seen hospitalizations involving Wyoming babies due to pertussis so far this year. Large outbreaks with infant deaths have happened in other states over the last couple of decades and we just don’t want that to happen here,” Van Houten said.

Van Houten said the Tdap adolescent/adult pertussis booster vaccine is important for those who spend time with new infants such as parents, grandparents and other people who take care of them. “If you are pregnant or planning on becoming pregnant, you should talk to your doctor about a Tdap vaccine, which can help protect infants,” he said. “Infants are most vulnerable and don’t yet have the protection a pertussis vaccine can offer.”

“In addition to our focus on protecting babies, we recommend all residents stay up to date with their pertussis vaccines for themselves,” Van Houten said. “Those who still become ill with pertussis after vaccination are less likely to have a severe infection.”

Pertussis typically begins with cold-like symptoms and perhaps a mild cough. Pertussis is often not suspected or diagnosed until a persistent cough with spasms sets in after one to two weeks. Infants and children can cough violently and rapidly with a loud “whooping” sound.

“Pertussis is not always recognized because it has been less common in the United States over the last several decades due to immunizations slowing its spread overall,” Van Houten said.

More information about pertussis can be found online at health.wyo.gov/publichealth/infectious-disease-epidemiology-unit/disease/pertussis/.