Diphtheria and strep throat: what to know

Strep throat is usually caused by group A Streptococcus and may cause a sudden sore throat, fever, painful swallowing, red or swollen tonsils and swollen glands. Diphtheria is a different bacterial infection that can create a thick grey coating in the throat and release a toxin affecting other organs. A sore throat itself cannot identify which infection is present.

Tonsillitis can describe inflamed tonsils from several causes, so the label does not automatically identify the germ. A clinician may examine the throat, ask about exposure and vaccination, and arrange a throat test when appropriate. Symptoms may overlap with viral illnesses, which need different management.

Arrange a GP consultation when a sore throat is severe, comes with fever or swollen glands, or does not settle as expected. Mention recent contacts, travel, vaccination history, rash, breathing changes and any medicine allergies. Avoid sharing food, drinks or utensils and wash your hands regularly while infection is being considered.

Take antibiotic treatment only when prescribed and complete the course as directed. Antibiotics may be appropriate for confirmed or strongly suspected bacterial infection, but they do not help most viral sore throats. Check whether you or household members need vaccination advice if protection against diphtheria is uncertain.

Seek emergency help for trouble breathing, inability to swallow saliva, rapidly increasing neck or throat swelling, a grey throat coating, confusion, collapse or severe dehydration. These signs can indicate airway compromise or a serious infection and should not wait for routine review.

Ask whether a throat test is needed, how to reduce spread at home, whether antibiotics are appropriate, and whether your diphtheria vaccination protection is up to date.