On Jan. 24, 2025, The South Dakota Department of Health reported the death of a child due to a co-infection of Pertussis and influenza. The last Pertussis death occurred in 2023 among a pediatric patient.

South Dakota was experiencing Pertussis cases in multiple communities and influenza activity state-wide. The Pertussis component of DTaP and Tdap vaccines and the influenza vaccine are the best protection against infection. Protection is highest among those fully vaccinated, but that protection decreases over time.

Pertussis is spread from person to person when breathing in respiratory particles from an infected person. The respiratory particles are spread when a person with pertussis sneezes or coughs. 

It usually takes seven to 10 days after exposure to develop symptoms. Early symptoms resemble the common cold with runny nose, low-grade fever, and mild cough which are more severe at night. Later symptoms (within two weeks) include numerous rapid coughs followed by a high-pitched whoop, and mucus discharge or vomiting following a coughing episode.

Antibiotics are effective at stopping a person who is sick from spreading pertussis. Five days of treatment is needed to stop the bacteria from spreading, even though the person may continue to cough. Without antibiotics, a person can spread the pertussis bacteria for 21 days.