(BIVN) – Health officials are tracking a “worrying rise” in pertussis (whooping cough) cases in the state of Hawaiʻi this year, with infants under 1 year old the most severely affected group. 

The Hawaiʻi Department of Health on Monday reported it has identified 203 cases of pertussis as of July 31, 2025, which is more than double the 84 cases identified in all of 2024. 

Cases have been reported in every county, “with the highest rates on Kaua‘i, Maui, and Hawai‘i Island”, health officials say. Although infants under 1 year old are the most severely affected group, there are also elevated case rates being seen among toddlers, children and adolescents. 

graphic provided by the Hawaiʻi Department of Health

From the Hawaiʻi DOH:

Pertussis is a highly contagious respiratory disease spread through the air via coughs or sneezes of an infected person. Initially, the symptoms resemble a cold but can progress to intense coughing fits. In children, coughing fits can be followed by a deep breath that makes a “whooping” sound. Health complications can be serious and even life-threatening, especially for infants and young children who are not fully vaccinated. Complications include pneumonia, seizures, apnea (a pause in breathing), encephalopathy (a disease of the brain) and death.

The most effective way to reduce the risk and severity of pertussis is through vaccination with either the DTaP (diphtheria, tetanus and pertussis) or Tdap (tetanus, diphtheria and pertussis) vaccines. DTaP has been in use for more than 30 years, and the first dose is recommended at 2 months of age. Tdap has been available for nearly 20 years and is recommended for pregnant women which helps protect their newborns as well as for adolescents and adults. See the DOH pertussis webpage for more details. 

“The high number of cases means there’s a greater risk of getting exposed to pertussis in the community. If you have not yet vaccinated your infant, please consider doing so to reduce the risk of hospitalization or even death,” said Dr. Kenneth Fink, DOH director. “Like with other vaccine preventable diseases, we continue to strongly encourage all individuals to remain up to date on recommended vaccinations to help protect both the person vaccinated and those in our families and communities who are most vulnerable.”

To protect infants who cannot yet complete the full vaccine series, DOH encourages a “cocooning strategy” which involves ensuring close contacts of a baby, including parents, siblings, grandparents, childcare staff, caregivers and healthcare providers, are up to date on their pertussis vaccines. This provides a circle of protection around the infant until they are old enough to get all the doses of vaccine to be fully protected.

The DOH continues to work closely with families, healthcare providers and schools to identify close contacts of cases, recommend testing, treatment when appropriate, and support public health measures to reduce further spread of pertussis.