Human Papillomavirus Immunisation Programme. Background

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1 Human Papillomavirus Immunisation Programme Background Recommending the use of a human papillomavirus (HPV) vaccine was first signalled in the New Zealand Cancer Control Strategy Action Plan Including HPV in New Zealand s Immunisation Schedule was recommended by the Ministry of Health s Immunisation Technical Working Group in November The Ministry s Statement of Intent identified the funding and implementation of a mass HPV immunisation programme as one of two new initiatives. The programme was announced in Budget The development of a highly effective vaccine against the major cancercausing types of HPV was an important opportunity for the primary prevention of cancer in New Zealand. About HPV Over 99 percent of all cervical cancer is linked to HPV infection. While most people clear the virus by themselves, those who have persisting infection can develop precancerous lesions. If the precancerous lesions are not detected by cervical screening and removed, over time they can develop into cervical cancer. HPV also causes genital warts, genital cancers and some mouth and throat cancers. Genital warts are the most commonly reported viral sexually transmitted infection in New Zealand. HPV affects an estimated eighty percent of sexually active women with the peak incidence of infection occurring in women between 16 and 20 years old. Most HPV cases have no symptoms and will clear by themselves. Both cervical cancer incidence and mortality have fallen dramatically in New Zealand (as in other developed countries) over the last decade, due to cervical screening. However approximately 160 New Zealand women are diagnosed with cervical cancer each year and on average 50 women die of the disease each year. In 2004 genital warts were the most commonly reported viral sexually transmitted infection by sexual health clinics in New Zealand, with 4018 new diagnoses in males and females. About the HPV Immunisation Programme Two HPV vaccines are licensed for use in New Zealand (Gardasil and Cervarix ). Both protect against HPV types 16 and 18 which cause 70 percent of cervical cancers. Page 1 of 7

2 Gardasil also protects against the strains of HPV (types 6 and 11) that cause 90 percent of genital warts. HPV vaccine (as Gardasil ) was added to New Zealand s Immunisation Schedule for girls in year 8 at school (or age 12 in primary care) from January There is also a catch-up programme for young women born on or after 1 January 1990 which began on 1 September HPV immunisation is given as three injections over 6 months. The aim of the HPV immunisation programme is to protect young women from HPV infection and the risk of developing cervical cancer later in life. The HPV vaccine does not protect against all types of HPV that can cause cervical cancer. Cervical screening is recommended for all women aged 20 to 70 if they have ever been sexually active. Together, HPV immunisation and screening offer women the best protection against cervical cancer. Eligibility for HPV immunisation Young women born in 1990 and 1991 have until 31 December 2011 and girls born from 1992 onwards have until their 20 th birthday to start the programme. School participation School boards of trustees were given the decision whether to allow the HPV immunisation to be given on their premises. Ninety-five percent of eligible schools have allowed the programme. This excludes schools in the Canterbury District Health Board area where the vaccine is only offered through primary care is the final year of the school-based catch-up programme. From 2011 onwards, HPV immunisation will only be offered through participating schools to girls in year 8, although it will continue to be available through primary care. Uptake Most DHBs phased the offer of HPV vaccine over two years so not all eligible girls were offered the programme in In ,763 girls and young women were eligible to receive HPV vaccine and 53 percent of them received dose 1. The following is a breakdown of the cohorts: 45% of young women born in 1990 and 1991 have started the programme, mainly through primary care. Page 2 of 7

3 59% of girls born between 1992 and 1996 who were offered the immunisation in 2009 have started the programme, mainly through participating schools. Achieving equity As of 25 March 2010, 246,580 girls and young women were eligible for HPV vaccine and 38 percent of them had received dose 1. To date 253,310 doses of HPV vaccine have been given (includes doses 1 to 3). A key achievement in 2009 was the equitable coverage in school-aged girls. Nearly all DHBs have greater coverage for Māori and Pacific girls compared to all. This is significant given the burden of disease experienced by Māori who traditionally have the lowest immunisation rate of any ethnic group and the highest rate of cervical cancer. Population Benefit As cervical cancer develops over 10 to 20 years it will be some time before population-wide benefits are seen in terms of reductions in cervical cancer rates. However, reductions in the number of abnormal smear test results (cervical abnormalities and pre-cancers) and genital wart diagnoses are likely to be seen more quickly. In time, the Ministry of Health expects that HPV immunisation will help halve the number of women in New Zealand who develop cervical cancer. It will also help reduce the incidence of other cancers related to HPV infection, such as vaginal cancer. Potential issues 1. Maintaining public trust and confidence in vaccines generally and HPV specifically. 2. HPV immunisation coverage rates are not maximising the opportunity to reduce the burden of cervical cancer for future generations. Gardasil - Vaccine safety Gardasil was approved for use in New Zealand by Medsafe. The vaccine was considered to have acceptable efficacy quality and safety in accordance with international guidelines and the requirements of the Medicines Act A summary of the known information about Gardasil for health care professionals is contained in the data sheet, published on the Medsafe website ( A similar summary for consumers is also available as a Consumer Medicine Information sheet on the Medsafe website. The documents are updated as necessary. Page 3 of 7

4 Medsafe in conjunction with the Centre for Adverse Reactions Monitoring and Medicines Adverse Reactions Committee continuously reviews the safety of all medicines and vaccines including Gardasil. This monitoring includes analysis of spontaneous reports of suspected adverse reactions to immunisation in New Zealand, Periodic Safety Update Reports provided every six months by the company, published literature and information from other medicines regulators. Periodic Safety Update Reports include: a summary of reported suspected adverse reactions in association with a medicine, an analysis of the reports with actions taken when appropriate, an overview of any regulatory actions taken and exposure data. To date the majority of reactions linked to vaccination with Gardasil and listed in the data sheet are those generally associated with vaccination: injection site reactions, dizziness, fainting, nausea, fever, headache, chills and tiredness. Rare but serious potential adverse reactions associated to Gardasil and listed in the data sheet include: Guillain-Barre syndrome and anaphylaxis. Guillain- Barre syndrome is a rare neurological disease usually caused by viral infection. It has also been associated with seasonal flu vaccines. Anaphylaxis can also occur in response to contact with peanuts and other food items, in some people. If anaphylaxis does occur, it can be treated. This is why people are asked to wait for 15 to 20 minutes after immunisation. Every vaccinator is trained and equipped to deal with such a reaction. Medsafe and its expert advisory committee the Medicines Adverse Reaction Monitoring Committee reviewed the United States Communicable Disease Centre analysis of all spontaneous reports associated with Gardasil in the United States Vaccine Adverse Event Reporting System database published in Both Medsafe and the Medicines Adverse Reaction Monitoring Committee agreed with the author s conclusions that most of the reported event rates for Gardasil were not greater than the background rates seen for other vaccines. There was higher than expected reporting of syncope (fainting) and venous thromboembolic events. The significance of these findings must be tempered with the limitations (possible underreporting) of a passive reporting system. It should be noted that the comparison group of all other vaccines would have largely comprised childhood and adult vaccination rather than adolescent vaccination. Adolescent girls immunised in a school based setting have previously been found to show high rates of fainting and have high rates of initiating oral contraceptive use, a risk factor for thromboembolism. The differences in the comparison groups may be sufficient to account for the study findings. Adverse Event Reports in New Zealand Page 4 of 7

5 The Centre for Adverse Reactions Monitoring reports suspected adverse events reports to Gardasil on a monthly basis to the Ministry of Health. It is important to note that a report of a suspected reaction to a vaccine does not necessarily mean that it has been caused by the vaccine. Healthcare professionals and consumers are encouraged to report any suspicions that an event may have been caused by vaccination. Therefore reports sent to the Centre for Adverse Reactions Monitoring may be: true adverse reactions to the vaccine anxiety events or nervousness about needles or the process of vaccination coincidental and would have occurred anyway. For these reasons summaries of reported events following vaccination are not lists of known or proven adverse reactions to vaccines and must not be interpreted and used as such. Suspected adverse reactions reporting rates are very variable and dependent on many factors. Therefore these data cannot be used to determine the frequency of adverse reactions to vaccines. Summaries of reported events cannot be used to directly compare the relative safety of vaccines. With any vaccine the following types of suspected side effects are expected to be reported. Injection site reactions Well-recognised events such as headaches, dizziness, muscle aches, mild fever and tiredness Mild allergic reactions such as mild rashes and itching. A few serious allergic reactions. Healthcare professionals giving vaccines are trained to spot the symptoms of serious allergic reactions and treat them. Events due to fear or anticipations of the needle injection such as fainting. Coincidental medical conditions New side effects. In New Zealand it is unlikely that rare side effects to vaccines will be detected as the population immunised is usually too small. Therefore Medsafe uses international data to help determine if these rare events may be due to vaccination. Medsafe discusses medicines and vaccine safety issues on a regular basis with other medicines regulatory authorities. At 31 January 2010, 242 suspected adverse events following HPV vaccine had been reported to the Centre for Adverse Reactions Monitoring. Most reports were of minor ailments, like arm pain or swelling, dizziness, nausea and/or vomiting. Reports are defined as serious using the internationally accepted criteria outlined below: Page 5 of 7

6 Results in death Is life-threatening Requires inpatient hospitalisation or prolongation of existing hospitalisation Results in persistent or significant disability/incapacity Requires intervention to prevent permanent disability/ incapacity Results in a congenital anomaly In addition to internationally accepted criteria the Centre for Adverse Reactions Monitoring have also considered that cases where the patient attended an Emergency Department or after-hours clinic to be serious. Using the above criteria 31 of the 242 reports were considered to be serious. Table 1: An overview of 31 adverse event reports considered serious to 31 January 2010 Number of reports Death 1 Life-threatening 1 Intervention required 1 Hospitalisation 4 Persisting disability 4 Emergency department attendance 20 In summary these serious cases comprised: One report of sudden death, six months after the final vaccination. The case has been investigated by CARM and Medsafe and the cause of death is currently undetermined. This case is before the Coroner. A single life threatening report of severe hypersensitivity reaction involving tongue swelling. An intervention report describing an injection site abscess that required surgical draining. Four reports of hospitalisation: o systemic symptoms including diabetes and eye problems, both of which had been diagnosed prior to vaccination o convulsions two weeks following vaccination o fainting episode resulting in overnight observation o Leukaemia reported; not attributed to vaccination. Four reports of persisting symptoms: o three reports describe general symptoms of muscle aches, headache and fatigue Page 6 of 7

7 o one report of hair loss 20 reports of emergency department attendance including: o nine reports of syncope (fainting) o seven reports of allergic-type symptoms such as rash o two reports of convulsion-like episodes, occurring immediately following immunisation and lasting longer than usually observed with a faint. o one report of severe arm pain and swelling o one report of Bell's Palsy (face paralysis) starting within one day of vaccination that may have been due to a recent infection. The Ministry of Health concludes on the basis of current evidence, both local and international, that the benefits of HPV vaccination continue to outweigh possible risks. Page 7 of 7