Vaccination is the safest treatment against infectious diseases

December 13, 2016

In the summer of 2015 Spain suffered from one of the saddest episodes related to vaccination or, in this case, no-vaccination. A six-year-old child died of diphtheria in Olot (Gerona, Spain). His parents decided never to vaccinate him against Corynebacterium difteriae, the bacteria that causes diphtheria. After his death, a profound debate has come back to society of the necessity of vaccines. The parents of the dead child, a bit late from my point of view, have already said publicly that they are sorry for what happened and they blame the anti-vaccine movements.

Should vaccines be compulsory?

As in many other European countries, in Spain it is not compulsory to vaccinate children although highly advisable by health authorities. It is only compulsory if it exists a serious danger for public health. It is not surprising therefore that outbreaks of diseases that are considered eradicated in determined areas come up from time to time. It was not long ago when an outbreak of measles occurred in southern Spain, with a death. Together with the diphtheria case, they have raised the big question in society: should it be obligatory by law to vaccinate children?

Experts are not convinced that obligation is the answer. Indeed, immunization levels in countries where vaccination is compulsory are similar to those in countries where vaccination is only advisable. It has always happened that a small percentage of the population is not vaccinated against common and rare diseases, and this is all the power anti-vaccination movements have in society, no more than 10%. Obligation would only lead to reinforcement of ideologies and perhaps an increase of people that voluntarily decide not to vaccinate their children. It is always much better to convince people of the advantages of vaccination, and how they overcome the risks. To achieve this, they need information and solid arguments against legends and myths about vaccines.

The strong myths anti-vaccines and why they are false

First of all I have to say that better hygiene and hand washing can help to prevent the spread of certain infectious agents but they do not eradicate them. Without vaccines against them, the diseases would resurge independently of the hygiene conditions. Poliomyelitis and measles would become common again without proper vaccination measures.

Do vaccines entail side effects? No one can assure that in 100% of cases there will be no side effects or deaths. There have been cases in which an over-reaction to a vaccine has led to the death of the person. But what is true is that the vast majority of people do not suffer from such side effects. What is more, when they occur they are generally limited to mild and temporary annoyances. A vaccinated person is more likely to suffer a serious illness from the infectious agent than from the vaccine itself, such as paralysis from polio or encephalomyelitis and blindness from measles. There will always be risks, but the advantages of vaccination will always overcome such risks.

It is also said that a mixed vaccine against diphtheria, tetanus and whooping cough, and also that one against poliomyelitis, can generate SIDS (sudden infant death syndrome) in those vaccinated. The truth is that there is no scientific research that supports this. What is true is that the vaccine is administered in a period of life in which SIDS can occur. In other words, SIDS would have occurred even without the administration of the vaccine.

A very serious mistake would be not to administer a vaccine against a specific disease because such disease has already been eradicated in the area the person lives. Infectious agents are still circulating in other parts of the world. In a highly interconnected world such agents can easily travel everywhere and infect virtually everyone. For example, in 2005 there were several outbreaks of measles in different parts of Europe such as Germany, Austria, France, Spain and Italy, and all the cases affected non-vaccinated people.

Some people think that the administration of more than one vaccine simultaneously can overload the immune system and produce side effects in children, but many investigations have already proved that this is not true. The only side effect is that the child suffers from less injections, and parents save time and money.

Influenza is just a mild annoyance and the vaccine is not very effective. Actually, influenza is a severe illness that produces more than 300.000 deaths per year and can produce serious infections and death mainly in immunocompromised people. The vaccine protects against the three strains that are more prevalent in any season. Even though it is true that an effective vaccine that protects against all strains of influenza has not been developed, it is still the best way to reduce the likeliness of getting flu and infecting others.

Natural immunization vs. vaccine immunization? Vaccines interact with the immune system to mimic a real infection but they do not produce the illness and they do not lead to other risks. However, natural infection of Haemophilus influenzae type B could lead to intellectual disability, or congenital defects in the case of rubella.

In 1998 a paper was published in which they talked about the relation between the vaccine against measles, mumps and rubella (MMR) and autism. The investigation contained a lot of inconsistency and the paper was removed from the journal. However, it was enough to observe a reduction in vaccination rates and the subsequent outbreaks of such illnesses. There is no scientific research that supports a relation between such vaccine and autism to date.

This is one of the most common arguments against vaccines is that they contain mercury. Actually, they contain thimerosal, a mercury-containing preservative used in some products apart from vaccines and, to date, there is no scientific research that demonstrates that the amount of thimerosal used in vaccines entails a danger for health. Picture taken from

Finally, I want to point out that a vaccine-preventable illness that only causes mild effects in us could be lethal for people in our environment. For example, adults can suffer from whooping cough and get over it, but it can cause death in infants.