diphtheria

American  

[dif-theer-ee-uh, dip-] / dɪfˈθɪər i ə, dɪp- /

noun

Pathology.

1. a febrile, infectious disease caused by the bacillus Corynebacterium diphtheriae, and characterized by the formation of a false membrane in the air passages, especially the throat.

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diphtheria British  

/ dɪf-, dɪf-, dɪpˈθɪərɪə, ˌdɪpθəˈrɪtɪk, dɪpˈθɛrɪk, dɪf- /

noun

1. an acute contagious disease caused by the bacillus Corynebacterium diphtheriae, producing fever, severe prostration, and difficulty in breathing and swallowing as the result of swelling of the throat and formation of a false membrane

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diphtheria Scientific  

/ dĭf-thîr′ē-ə,dĭp- /

1. An infectious disease caused by the bacterium Corynebacterium diphtheriae and characterized by fever, swollen glands, and the formation of a membrane in the throat that prevents breathing. Infants are routinely vaccinated against diphtheria, which was once a common cause of death in children.

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diphtheria Cultural  

1. An acute disease, and a contagious disease, caused by bacteria that invade mucous membranes in the body, especially those found in the throat. The bacteria produce toxic substances that can spread throughout the body.

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Discover More

In developed countries, diphtheria has been virtually wiped out through an active program of infant immunization.

Other Word Forms

• diphtherial adjective
• diphtheroid adjective

Etymology

Origin of diphtheria

1850–55; < New Latin < French diphthérie < Greek diphthér ( a ) skin, leather + -ia -ia

Explanation

Diphtheria is a serious disease that spreads between people through sneezes and coughs. Luckily, diphtheria is easily prevented with a vaccine that's commonly given to babies. Most people who get diphtheria can expect to spend a week or so feeling pretty awful, with a cough, sore throat, and fever. For others, diphtheria is dangerous and even deadly, killing tissues in the airway and making it difficult to breathe, and sometimes damaging the heart. In most of the world, diphtheria vaccines are readily available. In Greek, the word diphtheria means "leather," a reference to the leathery coating the disease can cause in the throat.

Example Sentences

In 1962, President Kennedy signed the Vaccination Assistance Act, which ensured that all children under five, regardless of income, could receive vaccines against polio, diphtheria, whooping cough and tetanus.

From Salon • Jan. 4, 2026

Outbreaks of measles, diphtheria and severe diarrhea are afflicting more children and taking place more frequently because of a drop in vaccinations, health officials in Somalia’s southwest state said.

From The Wall Street Journal • Dec. 4, 2025

As early as 2 months old, babies get a formulation called DTaP, which besides pertussis also protects against diphtheria and tetanus.

From Los Angeles Times • Nov. 22, 2024

The benefit of adding an adjuvant to a vaccine was first noted in the 1920s, when alum -- an aluminum salt -- was discovered to boost the effectiveness of a diphtheria vaccine.

From Science Daily • May 8, 2024

It is what physicians used to be engaged in at the bedside of patients with diphtheria, meningitis, poliomyelitis, lobar pneumonia, and all the rest of the infectious diseases that have since come under control.

From "The Lives of a Cell" by Lewis Thomas