Diphtheria

Diphtheria is a serious infectious disease that is caused by toxin-producing strains of the bacteria Corynebacterium diphtheriae and, less commonly, Corynebacterium ulcerans.

The toxins produced by these bacteria can cause two main types of illness:

• respiratory diphtheria – which involves the respiratory tract (nose, throat and airways)
• cutaneous diphtheria – which involves the skin.

Diphtheria can cause severe illness and death. Even with treatment, up to 1 in 10 people with respiratory diphtheria may die.

Before routine vaccination was introduced, diphtheria was a common cause of death in children. Although diphtheria is now rare in Australia, it can still be brought in by travellers returning from overseas countries where the disease remains common.

Because diphtheria can spread easily, vaccination remains important to protect individuals and the community.

Symptoms and complications of diphtheria

The type of symptoms depends on where the infection happens in the body.

Respiratory diphtheria symptoms may start gradually with a fever, sore throat and generally feeling unwell (malaise).

Within a few days, the toxins can cause an abnormal membrane to grow over the throat, which can lead to more serious symptoms such as:

• neck swelling
• swallowing problems
• breathing problems and suffocation.

If the toxins are released into the bloodstream, they can also cause other dangerous and potentially lethal complications including paralysis, heart damage and kidney damage.

Cutaneous (skin) diphtheria symptoms include:

• skin ulcers that are sore, inflamed and pus-filled, often surrounded by bluish grey skin patches
• worsening infection of existing skin sores or wounds.

Cutaneous diphtheria infections rarely cause the serious complications seen in respiratory diphtheria.

How diphtheria is spread

Diphtheria can spread through close or prolonged contact with an infected person. It can spread when someone coughs or sneezes, or by contact with saliva, mucus, or skin sores, and sometimes contaminated objects.

Some people with diphtheria may have very mild or no symptoms and not realise they are infected. However, they can still be contagious and unknowingly spread the bacteria to others and make them sick.

Priority groups

Some people are at greater risk of getting diphtheria or getting very sick from it.

People are at greater risk of getting diphtheria if they:

• are unvaccinated or under-vaccinated
• travel to countries where diphtheria is more common (including Asia, South Pacific, the Middle East and Eastern European countries)
• travel to areas of Australia where there is a current outbreak
• are in close contact or live with someone who has diphtheria
• live in crowded conditions
• live or spend time in warm, humid areas, especially for cutaneous diphtheria
• are laboratory workers who may be exposed to the bacteria.

People at greater risk of severe illness include:

• young children
• people who are unvaccinated or under-vaccinated
• people who are immunocompromised or have severe chronic medical conditions.

If you are at greater risk, it is especially important to make sure you are up-to-date with vaccination.

Diagnosis of diphtheria

Ways healthcare professionals can diagnose diphtheria include:

• taking a medical history (including symptoms, vaccination status and travel history)
• physical examination
• swabs of the throat (or wound) for laboratory testing.

Treatment for diphtheria

If diphtheria is suspected, treatment begins straight away.

Diphtheria is treated with antibiotics and anti-toxin to stop the effects of the bacteria.

Some people may need further treatment or hospital care, depending on the severity and complications of the illness.

Prevention of diphtheria

Vaccination is the best way to protect against illness and severe complications from diphtheria.

Practising good hygiene can help to stop diphtheria from spreading, such as:

• washing your hands to remove germs that can make you or others sick
• covering your mouth and nose with a tissue or your sleeve, when you sneeze or cough.

Vaccination against diphtheria

Vaccinations against diphtheria are part of routine childhood vaccination and are given in a combination vaccine known as ‘DTP’ vaccine, which contains vaccines against diphtheria, tetanus and pertussis (whooping cough).

Adults who have never been vaccinated against diphtheria are recommended to receive a course of diphtheria-containing vaccines.

A booster dose is needed every 5 to 10 years to stay protected.

The National Immunisation Program

Free diphtheria containing vaccine is available for:

• infants at 2 (can be given from 6 weeks of age), 4 and 6 months of age
• children at 18 months and 4 years of age
• adolescents in Year 7 (or age equivalent)
• pregnant women (ideally between 20 and 32 weeks) during every pregnancy, as part of the combined diphtheria-tetanus-pertussis vaccine.

Catch-up vaccinations are also available for people who did not receive vaccination against diphtheria as children:

• people up to 19 years of age
• refugees and humanitarian entrants aged 20 years and over.

More information is available at the National Immunisation Program Schedule.

Adults

A course of diphtheria-containing vaccines are recommended for adults who have never been vaccinated against diphtheria.

Adults who have been fully vaccinated in the past are recommended to receive a booster dose at the age of 50 years unless a booster dose has been documented in the previous 10 years. Adults should receive this dose as the combined diphtheria-tetanus-pertussis vaccine to also protect against pertussis (whooping cough).

Side effects of the diphtheria vaccine

Immunisations against diphtheria, tetanus and whooping cough are effective and safe.

Most side effects are mild and temporary, and do not require specific treatment:

• localised pain, redness and swelling at the injection site
• small lump at the injection site (this may last several weeks)
• low-grade temperature (fever)
• children may be unsettled and fatigued.

Seek medical help if:

• side effects are unexpected, persistent, or severe
• you’re worried about your or your child’s health.

Concerns about immunisation side effects

If the side effects following immunisation are unexpected, persistent, or severe or if you are worried about your or your child’s condition after a vaccination, see your doctor or immunisation provider as soon as possible or go directly to a hospital.

Immunisation side effects may be reported to SAEFVIC, the Victorian vaccine safety service.

Where to get help

• In an emergency, call triple zero (000)
• Emergency department of your nearest hospital
• Your GP (doctor)
• Your local council immunisation service
• Urgent Care Clinics – provide care for conditions that require treatment today but not an emergency response (extended hours)
• Nurse-on-Call Tel. 1300 60 60 24 – for expert health information and advice (24 hours, 7 days)
• Maternal and Child Health Line (24 hours, 7 days) Tel. 13 22 29
• Immunise Australia Information Line Tel. 1800 671 811
• SAEFVIC Tel. 1300 882 924 – see the SAEFVIC website for hours of operation
• Immunisation Program, Department of Health, Victorian Government
  Email: immunisation@health.vic.gov.au