Diphtheria a is highly infectious bacterial infection which can be fatal. Diphtheria is typically spread by coughing and sneezing, close contact with infected people or contaminated clothes and bedding. There is a safe and effective vaccine. Diphtheria can cause nose and throat infections: a tough ‘leathery’ grey/yellow membrane develops, that affects the soft palate, tonsils and throat. Lymph glands become swollen, prominent and tender, producing a ‘bull neck’. Symptoms include sore throat, difficulty and/or pain on swallowing, husky voice, fever, cough, headache and, if there is airway obstruction, breathing difficulties.