Catching infections is part of growing up. Parents expect their children to get coughs and colds and common diseases like chickenpox, which about 90% of children catch (it is not part of the immunisation schedule). Bed rest and time off school and work (for parents) is usually the result.
Young children are more vulnerable to infectious diseases than other age groups because their immune systems are less developed. In the early 21st century infectious diseases accounted for 55% of acute hospital admissions of children under five years old. Māori and Pasifika children under the age of five were more likely than those of European and other ethnicities to be hospitalised for infectious diseases, some of which – like rheumatic fever – have long-term health effects. While rheumatic fever is rarely found among children in Western Europe and North America, it is still a serious threat to the health of Māori and Pasifika children in New Zealand.
Rite of passage?
Some dangerous infectious diseases were so common in the 19th century that they were almost an accepted part of childhood. Diphtheria was rife in 1870s Christchurch but there is very little mention of it in the records of the Christchurch Board of Health for this period. At the same time the chair of the board questioned whether typhoid cases should be officially recorded because the disease was such a ‘normal’ cause of death.
The types of infectious diseases which affect the health of children and young people have changed over time, though some present in the 19th century remained in the 21st century. Typhoid, a bacterial infection associated with poor sanitation, was a major killer in the 19th century and was still present until the mid-20th century. Other dangerous diseases in this period included diphtheria and scarlet fever. Improvements to sanitation and rising living standards helped eliminate these as major causes of child death and illness.
While tuberculosis (TB) declined throughout the 19th century, and did not affect children to the same extent as other infectious diseases, it remained a dangerous illness in the 20th century. Infected children were sent to sanatoriums, where treatment was a regime of fresh air, sunlight and nutritious food. Effective drugs and vaccines were available from the 1940s and the sanatoriums closed over the next two decades. TB rates among children continued to fall after this, but resurged between 1992 and 2001 before dropping again.
Poliomyelitis (polio) was one of the most significant child and youth diseases of the first half of the 20th century. It was difficult to treat and not eliminated until vaccines were developed in the 1950s and 1960s.
Diseases in the 1990s and 21st century
While rising living standards, improvements in antibiotics and immunisation programmes controlled and minimised the impact of many infectious diseases by the late 20th century, they were not wiped out as some commentators had predicted. In the 1990s hospital admissions and deaths due to meningococcal disease increased sharply, which signalled an epidemic. Diseases associated with poverty, such as rheumatic fever, were more common in New Zealand than in other Organisation for Economic Co-operation and Development (OECD) countries in the early 21st century, while childhood diseases prevalent in the 19th century, such as measles and whooping cough, were still present.
Immunisation is the process by which the body develops a defence mechanism against infections and disease. Administering vaccines made of weakened viruses or bacteria is one way of creating immunity. In 2018 immunisation against 12 infectious diseases was available free of charge.
In 1885 the Observer newspaper published the ‘Vaccination funeral march’, a song written by an anti-vaccination group and sung to the tune of the popular hymn ‘Rock of ages’. It also referenced the Christmas carol ‘Hark the herald angels sing’: ‘Hark! the Herod-demons sing / Vaccination! Glorious King! / Hark! the weeping Rachels cry / Let us die, and let us die / Vaccination, skin and bone / Sits upon his gory throne / They have slain our bonny boys / Festered o’er their infant joys / Swine that rend us for our pearls / They have slain our little girls.’1
Vaccines have been available since the 1840s. Immunisation of infants was compulsory from 1864 to 1920 (apart from a brief period in 1872), and children were supposed to be immunised before they could attend school. In reality, many children were not immunised, and vaccines were not available for all diseases. From 1900 parents who had a conscientious objection to vaccination could apply for an exemption if their child was less than four months old. Since 1920 immunisation has been a matter of parental choice.
Immunisation has always been controversial. Some parents believe it is harmful, ineffective or unnecessary, and choose not to vaccinate their children. This in part accounts for New Zealand’s low immunisation rates compared to other OECD countries. Health authorities say vaccinations are safe, and the most cost-effective way to protect children from disease.