Diphtheria

No current outbreak declared. 1 case(s) recorded in 2024 (historical). Zero-tolerance monitoring active — any confirmed case triggers an alert.

What is it?

Diphtheria is caused by toxin-producing strains of Corynebacterium diphtheriae. Once a leading cause of childhood death worldwide, it is now essentially eliminated in countries with high vaccination coverage. No cases are expected in NYS, and any confirmed case represents a critical public health event requiring immediate response. Diphtheria remains a serious concern in countries with poor vaccination coverage.

How it spreads

Spreads through respiratory droplets from coughing or sneezing, or through direct contact with infected wounds or skin lesions. A person can be contagious for 2–4 weeks if untreated.

Symptoms

Sore throat, mild fever, and the development of a thick gray membrane (pseudomembrane) over the throat and tonsils that can obstruct breathing. The bacterial toxin can spread through the bloodstream and cause damage to the heart and nervous system, even weeks after infection.

Who is at risk?

Unvaccinated individuals of any age. People traveling to countries where diphtheria is still endemic (parts of Africa, Asia, Middle East). Adults whose vaccine immunity has waned (protection from childhood DTaP wanes over time; adults need Td boosters every 10 years).

What you can do

Vaccine information

DTaP for children (5 doses), then Td booster every 10 years for adults. Tdap replaces one Td booster and also provides pertussis protection — recommended once for all adults.

Any confirmed case in a county triggers an elevated alert. Updated manually when NYSDOH issues outbreak notifications.