Signs and symptoms of diphtheria may include:

• A sore throat and hoarseness
• Painful swallowing
• Swollen glands (enlarged lymph nodes) in your neck
• A thick, gray membrane covering your throat and tonsils
• Difficulty breathing or rapid breathing
• Nasal discharge
• Fever and chills
• Malaise

Signs and symptoms usually begin two to five days after a person becomes infected.

Some people become infected with diphtheria-causing bacteria, but they develop only a mild case of the illness or may even show no signs or symptoms of the disease. They're said to be carriers of the disease, because they may spread the disease without showing signs or symptoms of illness.

Skin (cutaneous) diphtheria
A second type of diphtheria can affect the skin, causing the typical pain, redness and swelling associated with other bacterial skin infections. Ulcers covered by a gray membrane also may develop in cutaneous diphtheria.

Although it's more common in tropical climates, cutaneous diphtheria also occurs in the United States, particularly among people with poor hygiene who live in crowded conditions.

In rare instances, diphtheria affects the eye.

When to see a doctor
Call your family doctor immediately if you or your child has been exposed to someone with diphtheria. If you're not sure whether your child has been vaccinated against diphtheria, schedule an appointment. Make sure your own immunizations are current.

©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.

The bacterium Corynebacterium diphtheriae causes diphtheria. Usually the bacteria multiply on or near the surface of the mucous membranes of the throat, where they cause inflammation. The inflammation may spread to the voice box (larynx) and may make your throat swell, narrowing your airway. Disease-causing strains of C. diphtheriae release a damaging substance (toxin), which can also involve the heart, brain and nerves.

The bacteria may cause a thick, gray covering to form in your nose, throat or airway — a marker of diphtheria that separates it from other respiratory illnesses. This covering is usually fuzzy gray or black and causes breathing difficulties and painful swallowing.

You contract diphtheria by inhaling airborne droplets exhaled by a person with the disease or by a carrier who has no symptoms. Diphtheria passes from an infected person to others through:

• Sneezing and coughing, especially in crowded living conditions (easily)
• Contaminated personal items, such as tissues or drinking glasses that have been used by an infected person (occasionally)
• Contaminated household items, such as towels or toys (rarely)

You can also come in contact with diphtheria-causing bacteria by touching an infected wound.

People who have been infected by the diphtheria bacteria and who haven't been treated can infect nonimmunized people for up to six weeks — even if they don't show any symptoms.

©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.

People who are at increased risk of contracting diphtheria include:

• Children and adults who don't have up-to-date immunizations
• People living in crowded or unsanitary conditions
• Undernourished people
• People who have a compromised immune system

Diphtheria is rare in the United States and Europe, where health officials have been immunizing children against it for decades. However, diphtheria is still common in developing countries where immunization rates are low. For example, large outbreaks of diphtheria occurred in the 1990s throughout Russia and the independent countries of the former Soviet Union, resulting in some 5,000 deaths. Control measures have since been implemented, but a risk of diphtheria remains in those areas.

Most cases of diphtheria occur in unvaccinated or inadequately vaccinated people. Diphtheria poses a threat to U.S. residents who may not be fully immunized and who travel to other countries or have contact with immigrants or international travelers coming to the United States.

©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.

Left untreated, diphtheria can lead to:

• Breathing problems. Diphtheria-causing bacteria may produce a toxin. This toxin damages tissue in the immediate area of infection — the nose and throat, for example. This localized infection produces a tough, gray-colored membrane — which is composed of dead cells, bacteria and other substances — on the inside of your nose and throat. This tough membrane, or covering, is dangerous because it can obstruct breathing.
• Heart damage. The diphtheria toxin may spread through your bloodstream and damage other tissues in your body, such as your heart muscle. One complication of diphtheria is inflammation of the heart muscle (myocarditis). Signs and symptoms of myocarditis include fever, vague chest pain, joint pain and an abnormally fast heart rate. Damage to the heart from myocarditis may be only slight, showing up as minor abnormalities on an electrocardiogram, or very severe, leading to congestive heart failure and sudden death.
• Nerve damage. The toxin can also cause nerve damage, targeting certain nerves such as those to the throat, making swallowing difficult. Nerves to the arms and legs also may become inflamed, causing muscle weakness. In severe cases, nerves that help control the muscles used in breathing may be damaged, leading to paralysis of these muscles and trouble breathing.

With treatment, most people with diphtheria survive these complications, but recovery is often slow. Diphtheria is fatal in as many as one in 10 cases.

©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.

If you have symptoms of diphtheria or have come into contact with someone with diphtheria, call your doctor right away. Depending on the severity of your symptoms and on your vaccination history, you may be told to go to the emergency room or call 911 for emergency medical help.

If your doctor determines that he or she should see you first, it's critical to be well prepared for your appointment. Here's some information to help you get ready, and what to expect from your doctor.

Information to gather in advance

• Pre-appointment restrictions. At the time you make your appointment, ask if there are any restrictions you need to follow in the time leading up to your visit, including whether you should be isolated to avoid spreading infection.
• Office visit instructions. Ask your doctor whether you should be isolated when you come to the office for your appointment.
• Symptom history. Write down any symptoms you've been experiencing, and for how long.
• Recent exposure to possible sources of infection. Your doctor will be especially interested to know if you have recently traveled abroad, and where.
• Vaccination record. Find out before your appointment whether your vaccinations are up to date. Bring a copy of your immunization record, if possible.
• Medical history. Make a list of your key medical information, including other conditions for which you're being treated and any medications, vitamins or supplements you're currently taking.
• Questions to ask your doctor. Write down your questions in advance so that you can make the most of your time with your doctor.

The list below suggests questions to raise with your doctor about diphtheria. Don't hesitate to ask more questions during your appointment at any time that you don't understand something.

• Could I have diphtheria?
• Are there any other possible causes for my symptoms?
• What kinds of tests do I need?
• What treatment approach do you recommend?
• Are there any possible side effects from the medications I'll be taking?
• How soon after I begin treatment will I begin to feel better?
• How long do you expect a full recovery to take?
• When do you expect I will be able to return to school or work?
• When do you expect I will be able to resume a normal activity level?
• Am I at risk of any long-term complications from diphtheria?
• Am I contagious? How can I reduce my risk of passing my illness to others?

In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment at any time that you don't understand something.

What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to talk about in-depth. Your doctor may ask:

• What are your symptoms?
• When did you first begin experiencing symptoms?
• Have you had a sore throat or difficulty swallowing?
• Have you had any trouble breathing?
• Have you had a fever? How high was the fever at its peak, and how long did it last?
• Have you recently been exposed to anyone with diphtheria?
• Is anyone close to you having similar symptoms?
• Have you recently traveled abroad? Where?
• Did you update your immunizations before traveling?
• Are all of your immunizations current?
• Are you being treated for any other medical conditions?
• Are you currently taking any medications?

What you can do in the meantime
If your doctor determines that you don't need to come in immediately, rest as much as possible while you're waiting for your appointment. Be extremely careful to avoid spreading your illness. Wash your hands frequently and avoid sharing personal items, such as drinking glasses, utensils and towels.

©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.

Doctors may suspect diphtheria in a sick child who has a sore throat with a gray membrane covering the tonsils and throat. Doctors confirm the diagnosis by taking a sample of the membrane from the child's throat with a swab and having the sample grown (cultured) in a laboratory. Your doctor should notify the laboratory that diphtheria is suspected.

Doctors can also take a sample of tissue from an infected wound and have it tested in a laboratory, to check for the type of diphtheria that affects the skin (cutaneous diphtheria).

If a doctor suspects diphtheria, treatment begins immediately, even before the results of bacterial tests are available.

©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.

Diphtheria is a serious illness. Doctors treat it immediately and aggressively with these medications:

• An antitoxin. After doctors confirm that a person has diphtheria, the infected child or adult receives a special antitoxin. The antitoxin neutralizes the diphtheria toxin already circulating in your body. The antitoxin is injected into a vein (intravenously) or into a muscle (intramuscular injection). But first, doctors may perform skin allergy tests to make sure that the infected person doesn't have an allergy to the antitoxin. People who are allergic must first be desensitized to the antitoxin. Doctors accomplish this by initially giving small doses of the antitoxin and then gradually increasing the dosage.
• Antibiotics. Diphtheria is also treated with antibiotics, such as penicillin or erythromycin. Antibiotics help kill bacteria in the body, clearing up infections. Antibiotics reduce to just a few days the length of time that a person with diphtheria is contagious.

Children and adults who have diphtheria often need to be in the hospital for treatment. They may be isolated in an intensive care unit because diphtheria can spread easily to anyone not immunized against the disease.

Doctors may remove some of the thick, gray covering in the throat if the covering is obstructing breathing.

There may be other complications of diphtheria that need treatment. Inflammation of the heart (myocarditis) is treated with medications. In advanced cases, a person with diphtheria may need the assistance of a machine that helps them breathe (ventilator) until the infection is successfully treated.

Preventive treatments
If you've been exposed to a person infected with diphtheria, see a doctor for testing and possible treatment. Your doctor may give you a prescription for antibiotics to help prevent you from developing the disease. You may also need a booster dose of the diphtheria vaccine.

Doctors treat people who are found to be carriers of diphtheria with antibiotics to clear their systems of the bacteria, as well.

©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.

Before antibiotics were available, diphtheria was a common illness in young children. Today, the disease is not only treatable but also preventable with a vaccine.

The diphtheria vaccine is usually combined with vaccines for tetanus and whooping cough (pertussis). Tetanus is a bacterial infection that leads to stiffness of the jaw and other muscles. Whooping cough is a bacterial infection of the respiratory tract. The three-in-one vaccine is known as the diphtheria, tetanus and pertussis, or DTaP, vaccine. The latest version of this immunization is known as the DTaP vaccine.

The diphtheria, tetanus and pertussis vaccine is one of the childhood immunizations that doctors in the United States recommend begin during infancy. The vaccine consists of a series of five shots, typically administered in the arm or thigh, and is given to children at ages:

• 2 months
• 4 months
• 6 months
• 12 to 18 months
• 4 to 6 years

The diphtheria vaccine is very effective at preventing diphtheria. But there may be some side effects. Some children may experience a mild fever, fussiness, drowsiness or tenderness at the injection site after a DTaP shot. Ask your doctor what you can do for your child to minimize or relieve these effects.

Rarely, the DTaP vaccine causes serious complications in a child, such as an allergic reaction (hives or a rash develops within minutes of the injection), seizures or shock — complications which are treatable.

Some children — such as those with progressive brain disorders — may not be candidates for the DTaP vaccine. But, the number of children to whom these restrictions apply is small.

You can't get diphtheria from the vaccine.

Booster shots
After the initial series of immunizations in childhood, booster shots of the diphtheria vaccine are needed to help you maintain immunity. That's because immunity to diphtheria fades with time.

The first booster shot is needed around age 12, and then every 10 years after that — especially if you travel to an area where diphtheria is common. Ask your doctor whether you're up to date on your immunizations. Be sure your child is up to date on childhood vaccinations before starting child care or school.

A booster shot of the diphtheria vaccine is given in combination with a booster shot of the tetanus vaccine. The tetanus-diphtheria (Td) vaccine is given by injection, usually into the arm or thigh.

Doctors recommend that anyone older than age 7 who has never been vaccinated against diphtheria receive three doses of the Td vaccine.

©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.

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 is a good way to help avoid 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.

©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.