Vaccines: between myth and reality

The alarming data

Last September, Paidòss (National Observatory on child and teenage health) presented at its National Convention a research that involved 1,000 parents of children aged 6 or less, interviewed between May and June 2015, and was conducted by Datanalysis (a public opinion research Institute, specialized in health). Aim of the survey was to investigate their perception on vaccines for possible adverse events and the legal judgements on the links between vaccines and autism. The results of the survey were quite alarming. Among the interviewed parents, 33% think that vaccines are more dangerous than the diseases they should prevent. Only 25.4% is convinced that, on the other side, vaccines are useful and important, and according to 36.6% their effectiveness depends on which vaccine or disease. According to 25% not all the vaccines are necessary, for 19.6% they are too many and 17% of the parents think that many vaccines administered at the same time could cause problems, for 12% their composition is possibly harmful. Long-term damages are a concern for 8% of the parents, another 8% fears side effects, 6% believes that the vaccines effectiveness is yet to be demonstrated and 3.9% thinks that the vaccines calendar is difficult to respect. Parents who vaccinate their children do not do it correctly. More than half of them (54.3%) had their children administered all the doses for compulsory vaccines, only 15% added the non-compulsory ones, but one over 4 parents never did any of it.
This survey follows a similar one conducted once again by Paidòss in 2014 that highlighted the parents’ fears of vaccines adverse effects, fostered by the news that can be founded in the websites against vaccinations.
The web in fact represents the source of information for 90% of the interviewed parents.
Only few months ago the Italian Health National Institute announced – and the news was reported by all media – the alarming decrease of vaccine coverage in Italy. This fear of vaccinations, that unfortunately concerns not just parents but sometimes the same healthcare professionals, practitioners included, is not justified and is not evidence-based.

False beliefs

The survey data discussed above recall the motivations many people present against vaccination, reasons that can be found in any website against vaccinations. It is believed that hygiene and healthy life should be enough to protect against infective diseases, that too many vaccines are associated in one single injection, that vaccines are administered to too young children and that vaccines weaken their immune system and cause severe disease like autism or SIDS; in short they assert that vaccine are useless and that they are bought by the State and administered to children mostly to favour the pharmaceutical industry.
You can find in the bibliography the references for websites or documents that explain in details why all these affirmations are not true, in the light of the available evidences.^1,2 The information behind this prejudice is therefore uncomplete or not correct. For example it is true that at birth and for few months the immune system is not yet perfectly mature, but vaccines are developed in a way that they activate only the part already able to respond. Delaying the start of vaccination cycle means to prolong the exposure of the child to diseases potentially severe and frequent in the first months of life, like pertussis or meningitis.
Even though they seem to be many, vaccines have been specialized and greatly evolved over the years, so as they only occupy a minimum part of our defence system capacity. For example, the bacteria that causes pertussis presents more than 3,000 substances that act as antigens, whilst the vaccine against pertussis has only three of them and the quantity of antigens present today into a hexavalent is 20 times less than the trivalent vaccine administered in the Eighties.

Safe vaccines

There is not enough space in this article to discuss all the false myths. We will limit then to some observations that principally regard the safety of vaccines.
Vaccines are medications and like all medications can cause adverse events. In medicine drugs are often used in primary prevention, i.e. to prevent diseases the patient does not suffer of. None refuses to take a tablet of acetylsalicylic acid to prevent heart failure or heparin to prevent thrombosis after a surgical intervention. It is rightly thought that the drug is effective in preventing these diseases and that, despite the adverse effects, the benefit-risk profile is largely favourable.
The risk linked to infective diseases is high. Fatal cases can be 1/3,000 for measles, 3/100 for tetanus, 1/20 for diphtheria and pertussis, 5/100 for poliomyelitis. Severe complications include paralysis for polio infection, hepatic cirrhosis for infection by hepatitis B virus, deafness for infection by parotitis virus, pneumonia for chicken pox virus infection.
On the contrary, vaccines are drugs with an optimal risk profile. In the Veneto Region, the Regional Programme Canale Verde for pre-vaccination consultation and monitoring of adverse events after vaccinations has been active since 1993. In more than 20 years of activity, with almost thirty million doses of vaccines administered, no fatal cases in the vaccinated children or adults has been reported and the severe adverse events were 1.5 every 100,000 administered doses, mostly febrile seizures resolved in a short time with no consequences. The most common adverse reactions were local reactions in the injection site or fever.

The story of autism

Why this exaggerated fear of vaccines, then? The adverse event more falsely associated to vaccines has been autism, which became popular toward the end of the Nineties after a study published by The Lancet by a British practitioner, Andrew Wakefield.³ The study was immediately criticized for its scientific methodology and few years later an enquiry conducted by a British journalist highlighted how the author had altered and falsified the data to support the results of the research. The other authors of the research retracted the conclusions, its publication was withdrawn in 2010 and Wakefield was barred from the UK medical register and from practicing medicine in the United Kingdom. Since then tens of studies published also by important journals presented data against this association. Some studies brought evidences that support the action of environmental or genetic factors that would act before the birth, during the foetus development in the mother’s womb, in favouring the onset of autism. Many others evaluated the association in epidemiological studies demonstrating the absence of a link between vaccines and autism. Among the most recent studies in 2014 the journal Vaccine published a meta-analysis⁴ that evaluated 5 cohort studies, for a total of 1,256,407 children, and 5 case-control studies, for a total of 9,920 studies. Either the types of studies did not provide any evidence of increased risk of autism or autism spectrum disorders linked to the vaccinations. The analysis also evaluated the possible role of component like thimerosal or mercury, without finding any relation. In 2015 another important study⁵ was published by JAMA. The study was conducted on 95,727 children, all with older siblings, some of whom autistic. Also this study, despite including high risk subjects for the familiarity with autism, excluded any association between vaccination and autism spectrum disorders.
Despite the long series of evidences the association between autism and vaccines keeps being promoted on the websites against vaccinations, on the basis of few minor works published by less important journals that report anecdotal cases or distort the results of more important researches in alleged revisions. Those against vaccines never cite the big studies as the one discussed above, but only single reports of autism listed by spontaneous reporting systems (which are always evaluated as not-correlated by the centres of vaccine-vigilance) or the sentences of judges that accept the request of compensation by the parents of autistic children. Recently the Court of of Bologna overturned the debated sentence of the judge of Rimini in 2012, who had granted a 200,000 euro compensation to the parents of a child vaccinated in 2002 and successively diagnosed with autism. The parents had brought also Wakefield’s study to support their thesis.

In conclusion

The web is a tremendous instrument of information, but it is also the place where more easily false news can circulate. The sources are rarely cited, the amount of contents is huge (because so many people can produce them) and the reliability and the independence of the authors on the websites are hardly evaluable. It is therefore not easy for a parent to navigate among so many information and to distinguish between the correct ones and those created ad hoc to support the interests of complementary medicines.
To conclude, a comment about the accusations often addressed to public healthcare, according to which vaccinations are recommended to favour the pharmaceutical industries that sell them. The topic of conflict of interest is certainly important and complicated in medicine. Sometimes, however, some simple reasoning should be enough to understand how these accusations are completely absurd. The public service that would allegedly give away money to the industries buying their vaccines is the same that unfortunately does not have the resources to buy the new drugs anti-hepatitis C for all the affected patients who would need them, it is the same that tried to limit practitioners and patients’ use of drugs like pump inhibitors or benzodiazepines, which would generate much higher expense and it is the same that combats to extend the use of generic medications to decrease their costs.
It is nevertheless more and more important that the healthcare professionals involved in vaccinations, national and regional authorities and researchers commit to a correct and transparent information about effectiveness and adverse events of vaccinations, without conflict of interests.