Pertussis (Whooping Cough)

2,875 cases in 2024 — 2.3× the 5-year baseline of ~1,248. Significantly elevated.

What is it?

Pertussis (whooping cough) is caused by Bordetella pertussis bacteria and is one of the most contagious diseases known. NYS had 2,875 cases in 2024 — significantly above recent-year averages, reflecting a national resurgence. Unvaccinated infants face the highest risk of severe illness and death; many are infected by adults and older children who don't know they have pertussis.

How it spreads

Spreads very easily through respiratory droplets when an infected person coughs or sneezes. Highly contagious from the start of the runny nose stage until about 3 weeks after coughing begins (or 5 days after antibiotics start).

Symptoms

Begins like a cold (runny nose, mild cough, low fever). After 1–2 weeks, progresses to severe coughing fits ending with a high-pitched "whooping" sound when inhaling, often followed by vomiting. Infants may not whoop but may have apnea (pauses in breathing) or turn blue. Cough can last months — pertussis is called the "100-day cough."

Who is at risk?

Infants under 12 months are at highest risk for severe disease and death, especially those too young to be fully vaccinated. Older children, teens, and adults typically have milder illness but spread it unknowingly. Vaccine immunity wanes over time.

What you can do

Vaccine information

DTaP for children (5 doses), Tdap booster for adolescents and adults. Tdap during pregnancy is especially important — it provides protection to the newborn until the baby can be vaccinated.

Based on NYSDOH annual communicable disease report. Threat level reflects 2024 case counts compared to the 5-year baseline.