Health & beauty
Kids' vaccinations
Introduction
We investigate why our vaccination rates are so low, and look at whether it really matters.
The Ministry of Health has spent the last 14 years trying to get our immunisation rates up to 95 percent. But rates among infants and toddlers remain low compared with other developed countries.
Low vaccination rates
Danny Hamer proudly says his age is five - and a half! He's also one of 77 percent of New Zealand kids who has been vaccinated in accordance with the National Immunisation Schedule (see below).
Danny's mother Karen says he needed a long nap after his first measles, mumps and rubella (MMR) jab but he's never had a serious reaction: "There's a lot of fear involved with child rearing. It's easy to see the hurt a needle gives, but hard to see the benefits when the disease isn't visible in the community."
Jacqui Richards has a different view of vaccines - one that's shared by between 3 and 6 percent of New Zealand parents:
"I read a variety of books before deciding not to vaccinate my kids. There were many reasons: too many vaccines in one injection, the programme starting too early (six weeks), a strong belief in the ability of a healthy immune system to fend off most illnesses, poverty being a large factor in spread of disease, a lack of trust of the information provided by the pharmaceutical industry and so it can go on."
Barriers to immunisation
It's not clear why the remaining 17 to 20 percent of parents don't immunise their kids. Low vaccination rates are linked to poverty levels, and Maori children are less likely to be fully immunised compared with other ethnic groups.
The Ministry of Health's chief adviser for child and youth health Dr Pat Tuohy says: "We are aware that some barriers [to immunisation] remain, even though immunisation is free ... one example is if both parents are working. We know it can be difficult to get children immunised because the parents' only free time to do so is after hours or on Saturday mornings."
Some health professionals think there are more pervasive problems. Paediatrician Diana Lennon - an expert in infectious diseases and population paediatrics - says poor immunisation rates are one example of our disorganised health system.
She says: "We don't have a decent primary care system; we don't have a decent system of vaccine delivery; and we don't really know what populations we're delivering to - it's getting better - but we're really not putting enough effort into it."
The National Immunisation Schedule
The National Immunisation Schedule is:
6 weeks:
- One shot that offers protection against Diphtheria/Tetanus/Whooping cough/Polio/Hepatitis B/Haemophilus influenzae type b
- One shot against Pneumococcal.
3 months:
- One shot that offers protection against Diphtheria/Tetanus/Whooping cough/Polio/Hepatitis B/Haemophilus influenzae type b
- One shot against Pneumococcal.
5 months:
- One shot that offers protection against Diphtheria/Tetanus/Whooping cough/Polio/Hepatitis B/Haemophilus influenzae type b
- One shot against Pneumococcal.
15 months:
- One shot that offers protection against Haemophilus influenzae type b
- One shot against Measles/ Mumps/Rubella
- One shot against Pneumococcal.
4 years:
- One shot that offers protection against Diphtheria/Tetanus/Whooping cough/Polio
- One shot against Measles/Mumps/Rubella.
11 years:
- One shot that offers protection against Diphtheria/Tetanus/Whooping cough
12 years:
- Three shots for girls only to prevent human papillomavirus.
Improving vaccination rates
Dr Pat Tuohy, the Ministry of Health's chief adviser for child and youth health, says there are already a number of measures to improve immunisation rates. These include:
- contacting parents to advise when their child's overdue for a jab
- providing services to families who don't have access to a GP
- lifting the profile of immunisation through public campaigns like the Meningococcal B campaign
- using combination vaccines to reduce the number of injections that children need with each visit
- monitoring immunisation rates in local practices.
The Australian example
Doctor Diana Lennon, an expert in infectious diseases and population paediatrics, says other countries have put an "awful lot of time and money" into improving rates.
The Australians have an immunisation rate in the early nineties. Australian GPs receive bonuses if they improve coverage among their patient base. The "GP Incentive Scheme" saw the amount of practices with 90 percent vaccination coverage rise from 12 percent in 1998 to 78 percent in 2003.
Australia also uses more hard-nosed programmes. Vaccinations are part of school entry requirements. Maternity and childcare benefits are suspended if parents don't follow the national schedule - unless they register as conscientious objectors.
These schemes became possible with the creation of the Australian Childhood Immunisation Register: a computerised database that holds immunisation details of Australian children.
New Zealand created its own register in 2005 (in the midst of the Meningococcal B campaign). Our National Immunisation Register allows authorised health officials to check whether or not a child is up-to-date with their vaccines. You can opt off the register if you want.
Why we immunise
Helen Petousis-Harris from the Immunisation Advisory Centre says: "Immunisation may be undervalued by virtue of its own success." What she means is that common childhood illnesses of the past are now rare thanks to vaccines. We've forgotten the damage these illnesses caused.
International experience tells us that infectious diseases can return in the absence of vaccines. In Japan, immunisation against whooping cough dropped around the mid-1970s. The number of whooping cough cases jumped from 393 cases and no deaths in 1974 to 13,000 cases and 41 deaths in 1979. Similar experiences occurred in Sweden and Great Britain.
To stop disease outbreaks, immunisation programmes must sustain rates of between 85 and 95 percent. Only 79 percent of Kiwi one-year-olds are immunised against measles (it's at 94 percent in Australia and 93 percent in the US). The Immunisation Advisory Centre is surprised that we haven't had a measles epidemic yet.
Economic evaluation
Critics argue that we invest too much faith and money in vaccinations. Chiropractor Tat Loo (pictured) says "Giving out a new vaccination appears to be more newsworthy, more important, and easier to spend public money on than more serious (though prosaic) health issues like New Zealand children not eating enough fruit and vegetables."
Dr Richard Milne is an Honorary Associate Professor at the University of Auckland and a private consultant in economic evaluation. He says immunisation programmes are subjected to more rigorous economic evaluation than most other forms of government investment in health.
"We ask questions such as: 'what will the programme cost the government and families? What health benefits will it deliver, and how soon? Does it provide good value for money compared with other expenditure on healthcare?'" The findings of this type of evaluation help the government to set priorities for its expenditure on public health.
For example, the government considered six new vaccines in 2007, but only two of these were subsequently included on the National Immunisation Schedule. The decision to fund these two vaccines, but not the other four, was based partly on economic evaluations.
Public opinion on vaccines
A 2002 survey of New Zealand mothers' attitudes towards immunisation found that 88 percent felt vaccines were effective.
However, 12 percent of respondents felt otherwise (they had concerns about vaccine safety and/or effectiveness). Similar beliefs today might prevent us from reaching the Ministry's target of 95 percent coverage.
Responses from our members ranged from those who thought vaccinations should be compulsory to those who wouldn't touch them with a barge pole. Several complained about poor-quality information: "The literature on immunisation is too generalised: dumbing down the issue to 'vaccinate your child or be labelled a bad parent' or 'don't vaccinate your child, it's Russian roulette!'"
Over-selling the message?
There was some criticism of the objectivity of Ministry of Health information during the two-year Meningococcal B campaign. For example, a 2007 study of 21 Christchurch parents published in The New Zealand Medical Journal reported that those who chose to immunise and those who didn't frequently found Ministry publicity unbalanced.
The Immunisation Awareness Society's Sue Claridge says "the campaign was based on fear and directed at school kids ... Kids - up until the age of 14 or 15 - should have no role in the decision-making process."
Research about the MeNZB vaccine carried out before the campaign showed many New Zealanders knew about the disease but didn't think it was relevant to them. So Ministry fact sheets and media campaigns tried to raise the perception of risk.
The campaign worked. Paediatrician Dr Lennon says: "To give three doses of vaccine to the entire child population of a country is pretty amazing. We didn't achieve 100 percent coverage - but the rate was pretty high and exceptionally high in Pacific Island kids who normally have very low immunisation rates."
Our Pacific Island community had the highest rate of the Meningococcal B epidemic strain: 36.9 cases per 100,000 people at the height of the epidemic compared with 24.9 per 100,000 for Maori and 6.0 per 100,000 for Europeans.
A new campaign
Another mass-immunisation campaign is now in full swing. Family Planning's Dr Christine Roke says Gardasil - the new human papillomavirus (HPV) vaccine - has the potential to reduce cervical cancer rates by 70 percent and genital warts by 90 percent as long as it's given to girls before they become sexually active.
The official HPV material's bright and cheery. Fact sheets feature a group of vibrant teenagers smiling at the camera: "Join the fight against cervical cancer". But email attachments have already begun to circulate claiming Gardasil causes a high rate of serious adverse reactions.
The Ministry says that Gardasil's one of the most extensively tested vaccines available today: "It was subject to clinical trials involving more than 20,000 women from 33 countries, including New Zealand. Based on its safety and efficacy, it has been licensed for use in more than 100 countries."
We asked the Ministry how it planned to address concerns about the HPV vaccine during the campaign. Dr Pat Tuohy says: "Public health nurses are providing information in schools. The best approach we can take is to be honest and up front with the information we have ... We'll provide access to health professionals through a toll-free 0800 number, information on our website and links to reputable clinical and reporting information."
Three concerns
Fuelling the concerns of some parents have been well-publicised but ultimately unfounded claims about the safety of various vaccines.
Vaccine-acquired polio
Summer outbreaks of polio occurred here throughout the 1950s until the Salk and Sabin vaccines stopped them. Nearly full immunisation against polio was achieved by 1961.
Since then, there have been no cases of "wild" polio in New Zealand but four confirmed and two suspected cases of "vaccine acquired polio". All six were linked to the Sabin oral polio vaccine (OPV). The OPV is a live vaccine that occasionally gains virulence in an infant's stomach.
We now use an inactivated polio vaccine (IPV) that's delivered with other vaccines like the diphtheria vaccine. According to the Immunisation Advisory Centre, 90 million doses of the IPV vaccine have been delivered worldwide with no severe adverse reactions reported.
MMR and autism
British gastroenterologist Andrew Wakefield published two studies in 1998 that suggested the MMR vaccine might lead to autism. His theory was that the vaccine could cause inflammatory bowel disease and prevent absorption of essential vitamins and nutrients leading to developmental disorders.
Since Wakefield published his theory numerous studies have failed to find a link between the MMR vaccine and autism. The World Health Organization (WHO) says: "Other scientists have not been able to reproduce the results claimed by Wakefield and his team."
Most of Wakefield's co-authors have also retracted their names from the original study: "We wish to make it clear that in this paper no causal link was established between (the) vaccine and autism."
MeNZB and chronic fatigue
Our MeNZB vaccine was based on a vaccine developed in Norway. The Norwegians reviewed their trials following media reports that the vaccine was linked to chronic fatigue (ME). The investigation sparked similar fears here.
However, the link between chronic fatigue and the vaccine was never proven. The World Health Organization gathered data from Meningococcal B campaigns in Cuba, France, New Zealand and Norway - it concluded: "the study provided no evidence of an increased risk of ME".
Better spent elsewhere?
The Ministry of Health report 'Looking Upstream' gives an insight into how we die. High-ranking causes of death include poor diet (linked to 30 percent of deaths), smoking (linked to 18 percent of deaths) and physical inactivity (linked to 10 percent of deaths). Infectious diseases are comparatively low on the list.
Critics of our National Immunisation Schedule argue the money for the Gardasil campaign could be better spent elsewhere. For example, the Immunisation Awareness Society's Sue Claridge notes 52 out of every 100,000 women die from heart disease every year - while only 3 die from cervical cancer: "In regards to public health expenditure, there are way more important things than cervical cancer."
The Ministry says the comparison doesn't take into account years of life lost: "Most women who get cervical cancer are relatively young so years of life lost is greater than years of life lost to heart disease."
It's also argued that there are better ways of dealing with specific diseases like Meningococcal B and cervical cancer than immunisation. For instance, Meningococcal B is a disease associated with poor and over-crowded housing. So why wasn't $222 million spent on improving housing in South Auckland? Better housing would reduce the rate of Meningococcal B - and other infectious diseases.
WHO says that better nutrition, less crowded living conditions, the development of antibiotics and lower birth rates have all contributed to a reduction in the incidence of infectious diseases. However, it also says that vaccines have had a significant impact on keeping the rate of infectious diseases in check.
Can we fix it?
The size of a health issue is only one factor; our ability to fix it is another question altogether.
Improving our nation's diet is difficult. But if Gardasil is as effective as studies indicate, then reducing the rate of cervical cancer and genital warts may only take three jabs in combination with ongoing smear tests. That's why organisations like Family Planning have pressed for the vaccine.
Chiropractor Tat Loo disagrees. He says that with more effort improving our diet might be no harder than developing a vaccine. "Take into account that the procedures and systems for getting a new vaccine into schools are now well-established mechanisms. The mechanisms to get healthy food into our schools have comparatively much less investment and development, so of course it looks harder."
Paediatrician Diana Lennon agrees that better housing may have helped stop the Meningococcal epidemic - but it would've taken too long. Even the development of a vaccine took far too long: "My view was that the advocacy for action took so long that the actual decay of the epidemic had started to occur. So there were many unnecessary cases [of Meningococcal B] because of political and Ministry of Health intransigence from 1996 onwards."
What's in a vaccine
So what is a vaccine? It's a substance that makes your immune system create antibodies. Antibodies help you combat infections.
All vaccines contain an ingredient called an antigen: weakened forms of a real germ ("live" vaccines) or pieces of a real germ ("subunit" vaccines). Antigens trigger a response from your immune system when they're injected.
Non-live vaccines usually need an adjuvant like aluminium salt to trigger a response. The adjuvant may contribute to reactions at the site of injection.
Other ingredients may include:
- Preservatives: sometimes vaccines need preservatives to stop contamination during storage. Phenoxyethanol is the most common preservative in vaccines. It's also used in cosmetics, baby care products and eye drops.
- Stabilisers: These prevent unwanted chemical reactions and include sugars like lactose, amino acids, and albumin (a protein often extracted from bovine blood).
- Buffers: Buffers stop changes in the vaccine's acidity level. Salt's the most common buffer.
- Diluents: Saline solution and sterile water are common diluents. Diluents make up most of the vaccine's volume.
- Emulsifiers: An emulsifier holds two liquids together. "Tween 80" is common in vaccines - it's also common in ice cream (where it holds milk protein and fats together).
Trace residuals may be present in some vaccines. These are leftovers from the manufacturing process: cellular culture fluids, egg proteins, yeast, antibiotics and formaldehyde. These are found at extremely low levels and often measure parts per million or billion.
Common side effects: There are minor side-effects associated with each vaccine. For example, the Hepatitis B jab sometimes causes a low-grade fever and swelling at the injection site. In addition to a low-grade fever, the MMR jab can also make children tired or drowsy. Minor side-effects can usually be fixed with rest, extra fluids and paracetamol.
The Immunisation Advisory Centre's Helen Petousis-Harris says severe allergic reactions (anaphylaxis) occur at a rate of around one per million doses of a vaccine.
Vaccine efficiency
No vaccine is 100 percent effective. Here's a glance at the efficiency of two of the jabs on the National Immunisation Schedule:
- Tetanus: 96 percent of people who receive all five tetanus jabs will be protected against the infection for 14 years; 72 percent will be protected for 25 years or more.
- Pertussis: The whooping cough vaccine only provides immunity for four to six years. Whooping cough is most serious in infants, so it's important the shots are given on time.
More information
- Health Outcomes Associates: www.hoa.co.nz
- Immunisation Advisory Centre: www.immune.org.nz
- Immunisation Awareness Society: www.ias.org.nz
- Ministry of Health: www.moh.govt.nz
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Report by Luke Harrison