A FEW REASONS TO SAY NO, THANKS, TO INFLUENZA/FLU VACCINES (EVIDENCE BASE COCHRANE REVIEWS versus INDUSTRIAL BASE CDC AND ECDC RECOMMENDATIONS)
1
Selection by Juan Gérvas, MD, PhD, Honorary Professor Public Health (Autonomous University, Madrid, Spain), Visiting Professor International Health (National School of Public Health, Madrid, Spain) jgervasc@meditex.es www.equipocesca.org
Madrid, Spain. September 2012
Main source of information:
http://www.thecochranelibrary.com/details/collection/978807/InfluenzaevidencefromCochrane Reviews.html
What says the CDC (Centers for Disease Control and Prevention, USA) about influenza/flu vaccines?
http://www.cdc.gov/flu/pdf/protect/visflu.pdf
All people 6 months of age and older should get flu vaccine. Vaccination is especially important for people at higher risk of severe influenza and their close contacts, including healthcare personnel and close contacts of children younger than 6 months.
What say the European Union and the ECDC (European Centre for Disease Prevention and Control) about influenza/flu vaccines?
http://ec.europa.eu/healtheu/europe_for_patients/flu_vaccination/index_en.htm
Following a proposal by the Commission, the Health Ministers of the European Union (EU) countries adopted on 22 December 2009 a recommendation on seasonal flu vaccination recommending that EU countries try and get 75% of the 'at risk' groups, including elderly and healthcare workers, vaccinated against seasonal flu by 2015.
What says the scientific evidence?
1- ABOUT HEALTHY CHILDREN
http://www.ncbi.nlm.nih.gov/pubmed/22895945
We could find no usable data for those aged two years or younger. Inactivated vaccines in children aged two years or younger are not significantly more efficacious than placebo. Influenza vaccines are efficacious in preventing cases of influenza in children older than two years of age, but little evidence is available for children younger than two years of age. There was a difference between vaccine efficacy and effectiveness, partly due to differing datasets, settings and viral circulation patterns. No safety comparisons could be carried out, emphasising the need for standardisation of methods and presentation of vaccine safety data in future studies. In specific cases, influenza vaccines were associated with serious harms such as narcolepsy and febrile convulsions. It was surprising to find only one study of inactivated vaccine in children under two years, given current recommendations to vaccinate healthy children from six months of age in the USA, Canada, parts of Europe and Australia. If immunisation in children is to be recommended as a public health policy, largescale studies assessing important outcomes, and directly comparing vaccine types are urgently required. The degree of scrutiny needed to identify all global cases of potential harms is beyond the resources of this review. This review includes trials funded by industry. An earlier systematic review of 274 influenza vaccine studies published up to 2007 found industryfunded studies were published in more prestigious journals and cited more than other studies independently from methodological quality and size. Studies funded from public sources were significantly less likely to report conclusions favourable to the vaccines. The review showed that reliable evidence on influenza vaccines is thin but there is evidence of widespread manipulation of conclusions and spurious notoriety of the studies. The content and conclusions of this review should be interpreted in the light of this finding.
2- ABOUT HEALTHY CHILDREN, ADOLESCENT, ADULTS AND ELDERLY
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2907815/?tool=pmcentrez
Live or inactivated vaccines are effective in reducing infection and in slightly reducing absence from work in adults, but there is no evidence that they reduce transmission, hospitalisation, pneumonia, or death.
There is poor-quality evidence from cohort studies that vaccines are effective in elderly people living in institutions, but there is little good-quality evidence for the elderly population in general.
http://www.ncbi.nlm.nih.gov/pubmed/17443504
Influenza vaccines are effective in reducing cases of influenza, especially when the content predicts accurately circulating types and circulation is high. However, they are less effective in reducing cases of influenzalike illness and have a modest impact on working days lost. There is insufficient evidence to assess their impact on complications. Wholevirion monovalent vaccines may perform best in a pandemic.
http://www.thelancet.com/journals/laninf/article/PIIS14733099(11)70295X/abstract
Influenza vaccines can provide moderate protection against virologically confirmed influenza, but such protection is greatly reduced or absent in some seasons. Evidence for protection in adults aged 65 years or older is lacking. Life attenuated influenza vaccines consistently show highest efficacy in young children (aged 6 months to 7 years).
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2749164/
The highest quality cluster randomised trials suggested that spread of respiratory viruses can be prevented by hygienic measures in younger children and within households. Evidence that the more uncomfortable and expensive N95 masks were superior to simple surgical masks was limited, but they caused skin irritation. The incremental effect of adding virucidals or antiseptics to normal handwashing to reduce respiratory disease remains uncertain. Global measures, such as screening at entry ports, were not properly evaluated. Evidence was limited for social distancing being effective, especially if related to risk of exposure—that is, the higher the risk the longer the distancing period. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2643439/?tool=pubmed
5.04). Study size was not associated with concordance, content of take home message, funding, and study quality. Higher citation index factor was associated with partial or complete industry funding. This was sensitive to the exclusion from the analysis of studies with undeclared funding.
3- ABOUT CHILDREN, ADULTS AND ELDERLY PATIENTS
Children receiving chemotherapy for cancer
http://www.escriber.com/userfiles/ccoch/file/CD006484.pdf
Paediatric oncology patients receiving chemotherapy are able to generate an immune response to the influenza vaccine, but it remains unclear whether this immune response protects them from influenza infection or its complications. We are awaiting results from well designed randomised clinical trials addressing the clinical benefit of influenza vaccination in these patients.
Children and adults with bronchiestasis
http://www.ncbi.nlm.nih.gov/pubmed/17636836
There is neither evidence for, nor against, routine annual influenza vaccination for children and adults with bronchiectasis.
Children, adolescents and adults with asthma
http://ajrccm.atsjournals.org/content/169/4/488.long
Influenza-related asthma exacerbations were of similar severity in both groups; they lasted 3.1 days shorter in the vaccine group (95% confidence interval, −6.2 to 0.002 days, p = 0.06). We conclude that influenza vaccination did not result in a significant reduction of the number, severity, or duration of asthma exacerbations caused by influenza. Additional studies are warranted to justify routine influenza vaccination of children with asthma.
http://www.ncbi.nlm.nih.gov/pubmed/11034684
There is not enough evidence to assess the benefits and risks of influenza vaccination for people with asthma.
Patients with chronic obstructive pulmonary disease (COPD)
http://www.ncbi.nlm.nih.gov/pubmed/16437444
studies, and was due to a reduction in exacerbations occurring three or more weeks after vaccination, and due to influenza. There is a mild increase in transient local adverse effects with vaccination, but no evidence of an increase in early exacerbations.
Patients with cystic fibrosis
http://www.ncbi.nlm.nih.gov/pubmed/19821281
There is currently no evidence from randomised studies that influenza vaccine given to people with CF is of benefit to them. There remains a need for a well-constructed clinical study, that assesses the effectiveness of influenza vaccination on important clinical outcome measures.
4 ABOUT ELDERLY PATIENTS IN GENERAL, A SHOT IN THE DARK
http://jid.oxfordjournals.org/content/201/2/186.full.pdf+htm
Because of the availability of effective influenza vaccines, randomized placebocontrolled trials would be unethical, but observational studies of influenza vaccine efficacy, which have predominated since the 1970s, have generally shown excellent vaccine effectiveness in preventing death from all causes, with reductions in mortality during influenza season of 30%–50%. Recently, this benefit has been called into question. Simonsen et al found that total excess mortality from influenza was in the range 5%–10%, making claims of 30%–50% reduction in mortality from the vaccine unrealistic. Jackson et al. reported that vaccination appeared to be even better at preventing death before the influenza season than during the time when the virus was circulating. This revealed a flaw in observational studies, and what had previously been taken for vaccine effectiveness was then thought to actually be selection bias.
http://aje.oxfordjournals.org/content/170/5/650.abstract
Vaccine coverage averaged 63%; excess mortality when the flu virus was circulating averaged 7.8%. In analyses that omitted weeks when flu circulated, the odds ratio measuring the vaccination mortality association increased monotonically from 0.34 early in November to 0.56 in January, 0.67 in April, and 0.76 in August. This reflects the trajectory of selection effects in the absence of flu. In analyses that included weeks with flu and adjustment for selection effects, flu season multiplied the odds ratio by 0.954. The corresponding vaccine effectiveness estimate was 4.6% (95% confidence interval: 0.7, 8.3).
http://www.ncbi.nlm.nih.gov/m/pubmed/22371873/
It is worth noting that results of several studies in the United States suggest that the benefit of influenza vaccine on mortality risk among the elderly is small. It is possible that the reduction in mortality risk is about 6%, the maximum attainable benefit of influenza vaccination among elderly people.
http://www.bmj.com/content/339/bmj.b4651
Please, may we have a randomized clinical trial now?
5- ABOUT HEALTH CARE PROFESSIONALS WHO WORK WITH ELDERLY
http://summaries.cochrane.org/CD005187/influenzavaccinationforhealthcareworkerswhowork withtheelderly
We conclude that there is no evidence that only vaccinating healthcare workers prevents laboratory-proven influenza, pneumonia, and death from pneumonia in elderly residents in long-term care facilities. Other interventions such as hand washing, masks, early detection of influenza with nasal swabs, anti-virals, quarantine, restricting visitors and asking healthcare workers with an influenza-like illness not to attend work might protect individuals over 60 in long-term care facilities and high quality randomised controlled trials testing combinations of these interventions are needed.
6- ABOUT THE DECLINE OF INDUCED PROTECTION
http://www.ncbi.nlm.nih.gov/pubmed/6357060
http://www.nature.com/nature/journal/v471/n7337/full/471157a.html
Natural protection last more than 50 years. Flu virus produces what we name as "immunity of original sin", which can last up to 50 years, as demonstrated the swine flu (H1N1) in 2009, with protection of those born before 1957. In a similar way, people aged 50 years and more are protected against H1N2 flu (Asian flu), because having circulated the virus 1957 to 1968.
http://jid.oxfordjournals.org/content/197/4/490.full
http://www.equipocesca.org/wpcontent/uploads/2011/09/fluvaccineterminator2011.pdf
7- VACCINE ADVERSE EFFECTS
http://www.ncbi.nlm.nih.gov/pubmed/22582209
The rate of Guillain Barré syndrome immediately following pH1N1 vaccination was 57% higher than in person-time unexposed to vaccine (adjusted rate ratio = 1.57, 95% confidence interval: 1.02, 2.21), corresponding to 0.74 excess Guillain Barré syndrome cases per million pH1N1 vaccine doses (95% confidence interval: 0.04, 1.56).
http://www.ncbi.nlm.nih.gov/pubmed/22470453
The 2009 vaccine-attributable risk of developing narcolepsy was 1:16,000 vaccinated 4 to 19 year-old (95% confidence interval 1:13,000-1:21,000).
http://www.dohc.ie/publications/pdf/Final_Report_of_National_Narcolepsy_Study_Steering_Comm ittee.pdf?direct=1
Twenty eight of these 32 cases occurred in children/adolescents aged 5-19 years old. Based on the first contact with health care because of narcolepsy symptoms, the incidence of narcolepsy during the primary follow-up time (01/04/2009 to 31/12/2010) was 5.8 [95% CI: 3.5-9.0] per 100,000 person years in the vaccinated and 0.5 [95% CI: 0.2-1.0] per 100,000 person years in the unvaccinated individuals. Thus was a highly statistically significant 13-fold higher risk of narcolepsy in vaccinated compared to unvaccinated individuals.
http://www.ncbi.nlm.nih.gov/pubmed/21929484
The 2010 trivalent influenza vaccine manufactured by CSL Biotherapies was associated with increased febrile reactions, including febrile convulsions, among Australian children.
8- INFLUENZA VACCINATION: POLICY VERSUS EVIDENCE
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1626345/?tool=pmcentrez
Each year enormous effort goes into producing influenza vaccines for that specific year and delivering them to appropriate sections of the population. Is this effort justified? No. Evidence from systematic reviews shows that inactivated vaccines have little or no effect on the effects measured. Reasons for the current gap between policy and evidence are unclear, but given the huge resources involved, a reevaluation should be urgently undertaken
.
Whatever policy is chosen, there is an urgent need to replace current practices with accountable policy-making. In this scenario, systematic synthesis of evidence should play a central role in making ethical decisions, in which the influence of lobbies, activism, ideology, and lucre are at least recognized.
http://www.equipocesca.org/wpcontent/uploads/2011/09/fluvaccineterminator2011.pdf