Re: Is the timing of recommended childhood vaccines evidence based?
The evidence base is purely based on the limited research that has been done (1), however vital vaccine safety research is missing in several important areas.
Has, due to vaccination, the overall burden of disease increased from (acute) infectious diseases to a greater burden of disease due to (chronic) non-communicable diseases?
The apparent success of vaccines coincides with overcoming poverty: malnutrition, poor hygiene, unclean drinking water, overcrowding and stress. These are the morbidity and mortality risk factors in relation to infectious diseases.
The following 11 areas need to be covered with systematic research to make sure that immunisations do no harm.
The ISAAC studies (International Studies on Asthma and Allergies in Childhood) show that in highly vaccinated affluent countries the incidence of non-communicable diseases (NCD) like asthma and allergies, is high. However, these studies do not mention vaccines as an environmental factor.
Studies are needed that check the prevalence of NCD like asthma and allergies in affluent highly vaccinated countries, between vaccinated and non-vaccinated children.
Furthermore, the immune system in the newborn might be primed in the first few months to react in an allergic fashion. This needs to be researched and could be done with a cohort of children who receive vaccines after the maturation of the immune system of the infant, rather than within the first few months of life. (2)
Vaccines have changed the microbiome. However, vaccines are again consistently ignored in articles discussing the effects of the microbiome. Vaccines are not mentioned in articles on the gut-brain axis, even though rates have soared in childhood anxiety, depression, ASD, ADHD.
Bacteria and viruses are of vital importance for human health. Guidelines are now produced to curb antibiotic prescribing. Never the less, the "infections are bad" paradigm still prevails. But hardly any research is done to check for benefits from these infectious diseases.
Frank Ryan in his book Virolution makes the case that evolution was made possible due to viruses changing our DNA.
Are infections needed for a healthy maturation of the body? For example are infections a protective factor against cancers? Do viral infections have epigenetic effects, for example can the mumps virus protect against testicular cancer?
In general with reference to childhood fevers, considering that: "Evidence indicates that survival benefits are accorded to individuals who achieve an increase in body temperature (i.e. fever) following infection" (3), could childhood fevers be an important protection against cancer over a life time?
Therefore, research is needed into the epigenetic effects of infections and the positive effects of childhood fevers in view of the upward cancer incidence trend. (4)
And considering the upward trend in autoimmune diseases, are for example gastro-intestinal commensals and infections (like rotavirus) also needed to protect the body from developing chronic inflammatory bowel diseases?
Public health has now started to vaccinate for economic reasons, but are birth cohorts in place comparing vaccinated with unvaccinated children to check whether this shift in vaccination reasoning is benefiting or harming the child? (5)
In the developing world there is a big push to vaccinate children but are any birth cohorts in place to check whether the balance in burden of disease shifts from acute to chronic diseases (NCD)?
As vaccines are given to everyone in society, scrutinising safety should be paramount to make sure that the overall burden of disease is not increased by vaccination, by having proper ongoing research in the 11 aforementioned areas in place.
1) Edwards KM, Maldonado Y, Byington CL, Jefferson T, Demicheli V. Is the timing of recommended childhood vaccines evidence based? BMJ 2016;352:i867 http://www.bmj.com/content/352/bmj.i867
2) Havinga W. Risk of asthma. Lancet. 2001 Jan 27;357(9252):313-4 http://www.thelancet.com/journals/lancet/article/PIIS0140-6736%2805%2971...
3) Repasky EA, Evans SS, Dewhirst MW. Temperature Matters! And Why it Should Matter to Tumor Immunologists. Cancer immunology research. 2013;1(4):210-216. http://cancerimmunolres.aacrjournals.org/content/1/4/210
5) Havinga W. Vaccinating for economic reasons. Acceptable? BMJ rr 15 May 2013 http://www.bmj.com/content/346/bmj.f2792/rr/645591
Competing interests: No competing interests