Diphtheria is a highly contagious and potentially life-threatening bacterial infection. It can cause swelling of the throat, making it impossible to breathe and swallow (respiratory diphtheria), and it can also affect the skin. While skin infection is the less severe form of diphtheria, it can still be spread and cause the more severe respiratory form of the infection.

Diphtheria is spread from close contact with an infected person, by breathing in droplets when an infected person coughs or sneezes or by direct contact with the skin sores of an infected person.

Symptoms of respiratory diphtheria start with a sore throat, fever and chills. The skin infection form of diphtheria starts with skin sores or ulcers.

Diphtheria has become rare in Australia since the introduction of diphtheria-tetanus-pertussis vaccines in the 1950s, but cases still occur occasionally in unvaccinated people. Diphtheria is included in the combination vaccine funded under the National Immunisation Program at 2, 4, 6 and 18 months and then at 4 years and 12–13 years. Booster vaccine doses are recommended at 50 and 65 years for people who have not had a diphtheria-containing vaccine in the previous decade.

In 2019, diphtheria vaccination coverage for Aboriginal and/or Torres Strait Islander children at 12 and 24 months was lower than that for other children (93.2% vs 95.1% for 12 months; 91.5% vs 93.2% for 24 months) but higher at 60 months (97.4% vs 94.6%).

Tetanus is a disease caused by bacteria that live in soil. The infection can be contracted through wounds that are contaminated with dirt. It cannot be passed from person to person.

Symptoms include stiffness of the jaw muscles (lockjaw); difficulty swallowing; and stiffness or pain in the neck, shoulder and back with severe painful spasms and difficulty breathing.

Tetanus has become rare in Australia since the diphtheria-tetanus-pertussis vaccination was introduced in the 1950s. Today, cases are mainly seen in older people who are not fully vaccinated.

Tetanus is included in the combination vaccine funded under the National Immunisation Program at 2, 4, 6 and 18 months, and then at 4 years and 12–13 years. Booster vaccine doses are recommended:

• at 50 and 65 years, for people who have not had a tetanus-containing vaccine in the previous decade
• after injuries where the skin is broken and potentially contaminated.

In 2019, tetanus vaccination coverage for Aboriginal and/or Torres Strait Islander children at 12 and 24 months was lower than that for other children (93.2% vs 95.1% for 12 months; 91.5% vs 93.2% for 24 months) but higher at 60 months (97.4% vs 94.6%).

Poliomyelitis (polio) is a highly contagious viral infection that can cause paralysis of various parts of the body. Infection occurs thought faecal–oral transmission, mainly through person-to-person contact. People who are infected can have either no symptoms or mild fever, headache, tiredness, nausea and vomiting. A small proportion of infected people develop paralysis.

Epidemics of paralytic polio occurred up until the 1960s in Australia, but the country was declared polio-free in 2000. However, until the disease is eradicated globally, there is still a risk of the virus being reintroduced. The most recent reported Australian case of polio was in 1972, in a person who acquired it during a visit to a country with known cases of polio transmission. Polio is included in the combination vaccines funded on the National Immunisation Program at 2, 4 and 6 months and at 4 years of age.

The 2019 polio vaccination coverage rate for Aboriginal and/or Torres Strait Islander children at 12 months was lower than that for other children (93.1% vs 95.1%) but higher at 24 months and 60 months (97.1% vs 96.3% at 24 months; 97.0% vs 94.2% at 60 months).

Rubella, also known as German measles, is a viral disease that usually causes a mild fever, rash and swollen lymph glands. It is highly infectious and spreads via small droplets produced through coughing or sneezing.

When rubella infection occurs in the first trimester of pregnancy, it can cause miscarriage as well as abnormalities in surviving babies; this is described as congenital rubella syndrome (CRS). These include:

• cataracts
• deafness
• heart problems
• intellectual disability.

While CRS is now rare, there remains an ongoing burden of hospitalisation and death in adults related to disease acquired congenitally in the past. Before the vaccination was introduced almost every child caught rubella. Most rubella cases reported in Australia occur in unvaccinated young adults aged 25 years and older.

In 2018, the World Health Organization certified that Australia has eliminated rubella.