Immunisation in the Bay of Plenty and Lakes

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1 Medical Officer of Health Report August 2017 Immunisation in the Bay of Plenty and Lakes The New Zealand Immunisation Schedule The current New Zealand vaccination schedule protects against the illnesses caused by fourteen different infectious viruses and bacteria. The range of illness and disability which can be averted is wide, ranging across gastroenteritis, pneumonia, meningitis, epiglottitis, septicaemia, congenital damage, deafness, blindness, paralysis, cirrhosis, and cancers. Premature deaths are also prevented. For example, from , nearly 900 (898) infants caught whooping cough (pertussis), 75% were hospitalised, and two infants died. Recent steps forward Increasing and more equitable uptake nationally One of the most crucial aspects of an immunisation programme is uptake. That is, what proportion of the population actually complete a full course of the recommended vaccinations appropriate for their age. In 2005, only 77% of two year old children in New Zealand were fully vaccinated. By 2017 this had risen to 92.8%. Increasing uptake and reducing inequities Here in the Bay of Plenty and Lakes district areas there has also been good progress. My reports to CPHAC in 2008 noted uptake at two years of age to be around 65% in both areas. By the end of 2016, the Bay of Plenty uptake was 88.6% and 91.6% in Lakes. - an considerable achievement. Additions to the immunisation schedule offering more protection As well as significant increases in uptake, the Ministry has also added a number of additional vaccines to the National Schedule offering further protection against infectious diseases. Pneumococcal vaccine for young children Invasive pneumococcal disease (in young children, pneumonia and meningitis) affected 100 per 100,000 children under two years of age in New Zealand in 2006/07. The pneumococcal vaccine (PCV) was added to the schedule in 2008 and by 2015 the infection rate had decreased to 11.8 cases per 100,000. Rotavirus vaccine for young children Prior to the introduction of the rotavirus vaccine in mid , almost all New Zealand children caught rotavirus by the time they were five years old. Although the gastroenteritis it causes varies in severity, a fifth of children require medical attention. Over 700 children under five years old were admitted to hospital in 2014 due to rotavirus infection. In 2015 the number had dropped to 99. HPV for boys and young adults The human papilloma virus (HPV) vaccine which was introduced in mid 2000s and in 2008 in New Zealand is the world s first vaccine specifically designed to prevent cancer, in particular cervical cancer but also some other cancers in both men and women.

2 It prevents infection with the HPV, which as the name suggests causes benign papillomas (more commonly known as warts) in people. It is an incredibly effective vaccine, pretty much guaranteeing protection from infection with the virus types that it covers. Moreover, now that the vaccine has been in use for over ten years in some countries, its real world impact is being seen. In Australia and Canada the incidence of genital warts in women under the age of 20, has fallen by almost half. The addition of boys to the programme this year, along with the extension of free and enhanced vaccine covering more strains to young people up to 26 years gives us the chance to considerably reduce cancer risk in the future. Early indications are that parents are taking advantage of the chance to protect boys as well as girls through the school programmes. Chickenpox vaccine for children The latest addition to the schedule is the varicella (chickenpox) vaccine. Chickenpox is one of the most infectious diseases, with most (95%) of people being infected by adulthood. Although it is generally a mild illness in children, because it is so common, a significant number of children can have much more serious infections. In families, children are often affected one after the other, causing considerable disruption. Adding chickenpox vaccine to the childhood schedule will reduce infection dramatically in the coming years. Never plain sailing recent unfavourable winds Easing in increasing uptake at national level After a number of years of steady increases in uptake (at two years of age) across New Zealand, progress has slowed over the past year. Recent falls in uptake locally Although overall uptake rates in our area have tended to be below the national average, the trend in uptake at two years has also been generally upwards from year to year. In 2017, however there have been some indications that the timeliness of immunisation, which is measured by uptake at eight months, has been weakening, particularly in the Bay of Plenty. Unhelpful publicity Vaccination uptake is not straightforward. Every child vaccinated is a decision made by parents to protect their child. People are busy, life is full of challenges, information might be less easy to find than it should. Immunisations are put off, forgotten, or, after consideration, declined. Immunisation is strongly recommended by almost all healthcare professions, and supported by most parents. Some people, however, do actively discourage immunisation usually for other people. Publicity surrounding anti vaccination views crops up from time to time, has been seen locally, and can affect the confidence of parents in immunisation. Importance of immunisation The Purpose of Community Immunisation The vaccination schedule is complex, and aims to achieve a number of outcomes, which vary from age to age, and vaccine to vaccine. The MMR (Measles, Mumps and Rubella) vaccine is a good example of this. Measles is only found in humans, is a serious illness with significant risk to young children, and is highly contagious. However, the vaccine is extremely effective, so it is possible to eradicate measles entirely. Achieving 95% uptake for this vaccine would protect individuals, especially children, protect people who cannot be vaccinated, and contribute to the global effort to eradicate measles. Rubella, on the other hand, is a fairly mild illness in most children and adults. However, rubella in early pregnancy can have devastating effects on the developing child resulting in

3 learning disabilities, cataracts, deafness, and organ damage. The main purpose of rubella vaccination is to prevent infections in women in order to prevent congenital rubella. In the case of tetanus vaccine, the aim is strictly individual protection. This illness is caused by common soil bacteria which produces a potent nerve toxin. The tetanus vaccine only protects a vaccinated person from the toxin. The Importance of High Uptake Immunisation protects individuals who choose to accept vaccination from a range of diseases; however, unlike most treatments, there is a wider family and community dimension to vaccination. A vaccinated family member is unlikely to become ill and infect their closest contacts. A vaccinated individual is unlikely to catch rubella and unwittingly infect a pregnant woman. At the wider community or national level, another issue arises. Where most people are immune to an infection such as measles (either through previous illness, or immunisation), a case of measles is very unlikely to spread, despite being very contagious. This is called community (or herd) immunity and protects individuals who can t be immunised for medical reasons, such as those receiving cancer treatments. Vaccine Safety The safety of all medicines is important in healthcare, however it is particularly crucial for immunisations, which are actively offered to well individuals to prevent rather than treat illness. They are also offered to individuals, at least in part, to protect others. An example of this is rubella vaccine being offered to boys, largely to protect pregnant women. Vaccines have to be, and be seen to be, as safe as possible. Process for Testing, Licensing, and Safety Monitoring of Vaccines in New Zealand Bringing a vaccine to the stage of routine use in a national programme takes many years. In a similar way to any new medicine, new vaccines progress through three stages of clinical trials assessing safety, immune response, and efficacy. The manufacturer then must satisfy Medsafe before a vaccine can be licensed for use in New Zealand. Once in use any clinically significant events are reported to the NZ Centre for Adverse Reactions Monitoring, and thoroughly investigated. Generally, vaccines will be licensed in many countries all of which will have similar requirements for safety and monitoring, therefore increasing the chances of detecting and assessing any rare and unforeseen issues. Safety Record of Vaccines Although minor side effects such a local tenderness at the vaccine site and mild fever are common, vaccines are well tolerated. Anaphylaxis, which is a severe allergic reaction, although rare, is a foreseeable and potentially fatal side effect, vaccinators are trained regularly in managing anaphylaxis, and vaccinate in controlled settings. Training of Vaccinators Most vaccines in the routine schedule are given by nurses in primary care. It is recommended that they have undergone the training and assessment to vaccinate as an authorised vaccinator and in practice most do. This means that in our area, each authorised vaccinator has had their training and assessment personally approved by one of the Medical Officers of Health. In addition, vaccinators are required to attend professional development for reauthorisation every two years. Protecting the community is a constant task In my native Scotland, a constant task is often referred to as like painting the Forth Bridge. The original cast iron rail bridge needs constant maintenance. Each time it is painted, it is time to start again. There is a needed for constantly refreshed and ongoing effort to protect our children.

4 Thousands of newborn babies arrive each year, many to first time parents and there are additions to the schedule, which are new for experienced parents. Each decision to protect a child is a new one, taken afresh. We need: Clear, reliable, up to date, evidence based and accessible information for all parents-tobe, parents and other relevant adults. Convenient and easy to access immunisation services Well trained staff delivering immunisation, Active support of immunisation by the wider healthcare community. Dr Jim Miller Medical Officer of Health July 2017

5 The Public Health Perspective - Immunisation July 2017 Immunisation is a highly effective way to reduce the transmission of a number of communicable diseases, as well as some cancers, at both individual and population levels. Inequalities in vaccination rates also contribute to disparities in health outcomes. Serious vaccine-preventable diseases are still prevalent in New Zealand All of the illnesses which are preventable by the national vaccination schedule, are already in New Zealand, or could be imported by travel. The risks are real and present. Immunisation is effective Immunisation is effective in preventing several serious diseases such as measles, whooping cough, pneumococcal disease, cervical cancer, and Hepatitis B. Vaccines are either a very small or inactivated fraction of a disease-causing (pathogenic) bacteria or virus. A small dose of carefully purified vaccine primes/prepares the immune response to recognise and quickly clear and recover from infection. Immunisation is safe Vaccines are extensively tested and monitored throughout the world. Side effects are minor, like local tenderness or mild fever, or very rare, for example, one in 1-2 million for anaphylaxis. Health professionals are trained to recognise and manage immunisations for all age groups, their anxieties and possible side effects. Immunisation is free Childhood immunisation in New Zealand is free before the age of 18, regardless of residency status. Some adult vaccinations in New Zealand are also free. Immunisation is recommended by health experts Immunisation is recommended by the World Health Organisation, the New Zealand Ministry of Health, and every other reputable medical organisation in the world. What immunisation does not cause Vaccines do not cause allergies, autism, immune overload, chronic fatigue, or promiscuity. Having concerns is understandable There is much information available to the public, especially via the internet: some of this is incorrect and can raise undue concerns. Healthcare professionals offering immunisation have access to reliable information and the skills to discuss the risks and benefits of immunisation. We encourage people to speak with their doctor, practice nurse, Public Health Nurse, or to phone the University of Auckland s helpline: 0800 IMMUNE