Read condition-specific symptoms and clinical context for Clostridium perfringens. A fast-growing anaerobe behind one of the commonest causes of food poisoning, and behind gas gangrene in damaged tissue.
PHAC describes C. perfringens as non-motile, anaerobic, Gram-positive spore-forming bacteria whose vegetative cells are rod shaped and pleomorphic and occur in pairs or short chains, forming highly resistant spores. Seven toxigenic types A to G are recognised, of which A, C and F strains are pathogenic for humans; alpha toxin is produced by all strains. PHAC estimates 1 million cases of foodborne illness every year in the United States and 5 million cases in the European Union, and 1,000 to 3,000 gas gangrene cases reported yearly in the United States. The same species therefore produces an illness that usually resolves within 24 hours and a rapidly destructive wound infection, depending on toxin type and where it grows.
PHAC gives an incubation period of 8 to 24 hours and describes the illness as usually mild and self-limiting in healthy individuals, with symptoms resolving within 24 hours.
Possible symptoms: Watery diarrhea; Intestinal cramps; Nausea.
PHAC describes the illness as usually mild and self-limiting in healthy individuals with symptoms resolving within 24 hours. Prolonged or severe illness, or illness in a vulnerable person, needs medical assessment.
PHAC describes type A strains causing clostridial myonecrosis, with breakdown of muscle and subcutaneous tissue, an incubation period of 1 to 4 days, and mortality of 5 to 30% with prompt treatment and almost 100% without treatment.
Possible symptoms: Severe pain; Swelling of the affected area; Tenderness and pallor; Discolouration of the skin; Blood-filled blisters.
PHAC gives mortality of 5 to 30% with prompt treatment and almost 100% without treatment, so this is a surgical and medical emergency. It is a wound infection, not a consequence of the food-poisoning form.
C. perfringens spores are common in the environment and in foods, and their presence does not mean illness will follow.
PHAC describes the organism in humans and a large number of mammals and in poultry, and states that it is not directly transmitted from person to person. Illness depends on how many organisms are eaten and on the toxin type, which is why the food-poisoning form is associated with foods held at the wrong temperature rather than with any contact. The bundled sheet gives no symptom list for exposure without illness, and none is invented here. This profile makes no claim about long-term human intestinal carriage, which is not stated in the cited sheet.
Safe cooling and holding of cooked foods is food-safety guidance from food-safety authorities. Symptoms are assessed clinically.
Source check: 2026-09-20. Educational content; independent scientific review remains pending.