Diphtheria

WHAT IS DIPHTHERIA?

Diphtheria is an infectius disease caused by the corynebacterium diphtheria. This is an acute upper respiratory tract infection and sometimes can infects the skin.

Diphtheria spreads from person to person by direct contact and via droplets in the air during sneezing or coughing. Unpasteurized milk and inanimate objects may also spread the bacteria. The incubation period is from one to seven days, usually around two days.

Diphtheria has been eliminated from many developed countries but it is still common in other areas, such as African countries, South America, Vietnam and other parts of South East Asia, and the Indian Subcontinent. In 1990 there was an epidemic in Russia. This was poorly controlled and led to the resurgence of diphtheria in many countries of the former Soviet Union.

WHAT ARE THE SYMPTOMS?

The disease often starts with a sore throat, fever, headache and feeling generally sick. The throat may not be particularly painful, but Lymph nodes in the neck can be very large, giving an appearance of "bull-neck", especially in severe cases. The throat phase can last several days, and the membrane can be thick enough to obstruct breathing. Alternatively, the initial site of infection may be the nose, resulting in a bloodstained discharge from one nostril. In the tropics, sometimes the only symptom is a skin ulcer which is very slow to heal and is covered by a grey membrane.

WHAT ARE THE COMPLICATIONS?

Complications can set in a week or two after the initial symptoms. Involvement of the heart muscle causes low blood pressure and a variety of abnormal heart rhythms that can be fatal.

Diphtheria toxin can also attack the nervous system, causing paralysis of the roof of the mouth and therefore could cause trouble in speaking and swallowing. The eye muscles may also be affected. Less often, other nerves are involved, for instance those that control breathing, which can be fatal. Nerve involvement can continue to develop up to three months from the start of the illness.