Diphtheria signs and symptoms usually begin 2 to 5 days after a person becomes infected. Signs and symptoms may include: 
A thick, gray membrane covering the throat and tonsils
A sore throat and hoarseness
Swollen glands (enlarged lymph nodes) in the neck
Difficulty breathing or rapid breathing
Nasal discharge
Fever and chills
Tiredness
 In some people, infection with diphtheria-causing bacteria causes only a mild illness — or no obvious signs and symptoms at all. Infected people who stay unaware of their illness are known as carriers of diphtheria. They're called carriers because they can spread the infection without being sick themselves. Skin (cutaneous) diphtheria A second type of diphtheria can affect the skin, causing pain, redness and swelling similar to other bacterial skin infections. Ulcers covered by a gray membrane also may be a sign of skin diphtheria. Although it's more common in tropical climates, diphtheria on the skin also occurs in the United States. It may happen especially among people with poor hygiene who live in crowded conditions.