Diphtheria is a potentially fatal contagious bacterial infection that mainly affects the nose and throat, and sometimes the skin. Diphtheria is caused by the bacterium Corynebacterium diphtheriae.
Diphtheria affects people of all ages, but most often it strikes unimmunized children. In temperate climates, diphtheria tends to occur during the colder months. In 2000, 30,000 cases and 3,000 deaths of diphtheria were reported worldwide.
Diphtheria is highly contagious. It is spread by coughs, sneezes or by contact with someone with diphtheria or items belonging to them, such as bedding or clothing.
The infection is usually caught after being in close or prolonged contact with someone who has the condition or is carrying the infection. For example, you may catch diphtheria from someone you live with.
What are the Symptoms?
The symptoms of diphtheria usually begin two to seven days after you become infected. The time it takes for symptoms to develop is called the incubation period.
Some people don’t experience any symptoms, while others have mild symptoms that are similar to those of the common cold.
If you have diphtheria, a grey-white coating (membrane) can develop inside your throat. It covers the back of your throat and tonsils, and can obstruct your breathing.
Symptoms of diphtheria also include:
a high temperature (fever) of 38C (100.4F) or above
fatigue (extreme tiredness)
difficulty swallowing or pain when swallowing
foul-smelling, bloodstained nasal discharge
swollen glands (nodes) in the neck
pale, blue skin
drooling (especially in babies)
a general feeling of uneasiness or discomfort
Additional symptoms may occur as the infection progresses, including:
changes in vision
signs of shock, such as pale and cold skin, sweating, and a rapid heartbeat
Older people and people with a weakened immune system are more at risk of the effects of diphtheria. The most serious cases can be fatal.
An estimated 5-10% of people who get the infection will die from complications of diphtheria, such as breathing difficulties, inflammation of the heart (myocarditis) or problems with the nervous system.
Diphtheria that affects the skin
Diphtheria can occasionally affect the skin rather than the throat. This is known as cutaneous diphtheria.
If you have cutaneous diphtheria, you will develop pus-filled spots on your skin, usually on your legs, feet and hands. These blisters and spots will form into a large ulcer surrounded by a red patch of discoloured, sore-looking skin. The ulcer usually heals within two to three months, but it's likely to leave a scar.
Your doctor will likely perform a physical exam to check for swollen lymph nodes. They’ll also ask you about your medical history and the symptoms you’ve been having.
Your doctor may believe that you have diphtheria if they see a gray coating on your throat or tonsils.
A diagnosis of diphtheria can be confirmed by taking a sample of cells from the throat, nose or wound on the skin and send it to a laboratory for testing. This will be examined to see whether the bacteria that cause diphtheria are present.
Diphtheria must be treated quickly to prevent serious complications developing. If diphtheria is suspected, treatment will begin before any test results are confirmed.
If diphtheria is suspected, you will be immediately admitted to an isolation ward in hospital to stop the infection spreading to other people.
If the grey-white membrane is making it difficult for you to breathe, some or all of it will be removed.
Those who develop heart and nervous system complications will need specialist treatment, and may need to be admitted to the intensive care ward.
A diphtheria infection is treated using two types of medication:
antibiotics to kill the diphtheria bacteria
antitoxins to neutralise the effects of the toxin produced by the bacteria
Most people who have diphtheria require a 14-day course of antibiotics. After this time, you'll have tests to find out if all the bacteria have gone. If diphtheria bacteria are still present, you may need to continue taking antibiotics for another 10 days.
Once you have completed the treatment, you won't be infectious to other people. However, you won't be able to leave the isolation ward until tests show that you're completely free of infection.
Testing and treating close contacts
Anyone who has had close contact with you, such as family or household members, visitors and anyone you have kissed or had sex with, should visit a doctor immediately to be checked for signs of diphtheria.
Your close contacts will be prescribed antibiotics. It's very important that they finish the course. If necessary, they will also be given a booster dose of the diphtheria vaccination.
Any healthcare worker who has cared for someone with diphtheria may also need to be tested and treated.
The risk of contracting diphtheria from work colleagues or school friends is very low.
Cutaneous diphtheria is diphtheria that affects the skin rather than the throat. It's treated by thoroughly washing any wounds infected with soap and water. You'll be tested two weeks later to make sure that all of the bacteria have gone.
Lifestyle and home remedies
Recovering from diphtheria requires lots of bed rest. Avoiding any physical exertion is particularly important if your heart has been affected. You may need to stay in bed for a few weeks or until you make a full recovery.
Strict isolation while you're contagious also is important to prevent spread of the infection. Careful hand-washing by everyone in your house helps prevent spread of the infection. Because of pain and difficulty swallowing, you may need to get your nutrition through liquids and soft foods for a while.
Once you recover from diphtheria, you'll need a full course of diphtheria vaccine to prevent a recurrence. Having diphtheria doesn't guarantee you lifetime immunity. You can get diphtheria more than once if you're not fully immunized against it.
How is Diphtheria Prevented?
The most effective way to prevent diphtheria is to get vaccinated and ensure all your vaccinations are up to date.
Vaccines are routinely used to prevent diphtheria infection in almost all countries. The vaccines are derived from a purified toxin that has been removed from a strain of the bacterium.
All children should be vaccinated against diphtheria as part of the routine childhood vaccination schedule.
Adults should consider having a booster vaccine when travelling to parts of the world where diphtheria is widespread.
What are the Risk Factors for Diphtheria?
Children in the United States and Europe are routinely vaccinated against diphtheria, so the condition is rare in these places. However, diphtheria is still fairly common in developing countries where immunization rates are low. In these countries, children under age 5 and people over age 60 are particularly at risk of getting diphtheria.
People are also at an increased risk of contracting diphtheria if they:
aren’t up to date on their vaccinations
visit a country that doesn’t provide immunizations
have an immune system disorder, such as AIDS
live in unsanitary or crowded conditions
What is the prognosis of diphtheria?
The prognosis of diphtheria ranges from good to poor, depending upon how early the infected patient is treated, and how the patient responds to treatment. If the patient develops sepsis or bacteremia, or if there's cardiac involvement, the prognosis is usually poor. The mortality (death) rate is highest in patients less than 5 years old and in patients that are older than 40.