To coincide with European Immunisation Week, marked across Europe between April 24 and 30, Charmaine Gauci writes about the importance of vaccination for people’s health and well-being.
Vaccination, one of the best public health tools acquired over time, prevents disease, protects life and is a strong foundation for lifelong health and well-being. The added value of vaccination is that it protects against infectious diseases of a whole population, not only the person vaccinated.
Since the introduction of vaccination, myths and misconceptions regarding vaccination have spread, leading to vaccine hesitancy – which in turn is responsible for the emergence and spread of vaccine-preventable diseases.
Many people seek sources of information that are unreliable and hence it is easy for false concepts to develop. It is highly recommended that advice is sought from reputable sources. Many of the misconceptions have revolved around the measles, mumps and rubella (MMR) vaccine. It is important to outline the true facts.
In 1980, before measles vaccination was widely available, 2.6 million deaths were caused globally. It is a common misperception that measles is a harmless disease, probably due to the vaccination’s success. Many people, especially the younger generations, have never seen someone with the measles infection and do not know how severe it can be.
In fact, measles can be a severe infection that cannot be directly treated with antivirals. Thus, once infected, only symptoms such as high fever can be treated. Complications occur with about 30 per cent of measles infections. They range from ear infections, diarrhoea and related dehydration to severe respiratory infections such as pneumonia and involve sequelae such as blindness or encephalitis.
Most measles-related deaths occur due to the complications associated with measles. Supportive care may only lower the probability of severe complications. Globally, more than 95 per cent of measles deaths occur in low-income countries with weak health infrastructures.
However, measles-related deaths also occur in developed and industrialised European countries. Measles killed 72 children and adults in the European region in 2018. According to data from the European Centre for Disease Prevention and Control, 82,596 people in 47 of 53 countries contracted measles.
In countries reporting hospitalisation data, nearly two-thirds (61 per cent) of measles cases were hospitalised. The total number of people infected with the virus in 2018 was the highest this decade. In fact, it was three times the total number reported in 2017 and 15 times the record low number of people affected in 2016.
MMR vaccines provide protection against measles, mumps and rubella without causing the development of severe symptoms, complications or sequelae that are associated with the diseases. Mild symptoms such as rash or fever may occur after vaccination in three to five of 100 individuals, as MMR is a live-attenuated vaccine. It is a common myth that it is better to get immunity by getting the disease than by receiving the vaccine. However, vaccinations elicit specific immune responses in the immune system, similar to the way an infection would, producing specific antibodies against the disease without developing severe symptoms, complications and sequelae of the actual disease.
Some combination vaccines contain multiple vaccines against different diseases, such as the MMR vaccine, which contains vaccines against measles, mumps and rubella. This way, the organism is protected against different diseases through only one shot. It is a common myth that giving a child the MMR combination vaccine increases the risk of harmful side effects and that it can overload the immune system.
The immune system can deal with a very large number of antigens at the same time. In fact, every day foreign substances found in dust and dirt trigger a child’s immune responses. A sore throat or a common cold exposes a child to more antigens than does the vaccine. The immune system is highly active. Other studies further show that vaccines do not weaken the immune system.
Since its introduction, around 575 million doses of MMR vaccine have been administered worldwide. It has an excellent safety record. A common myth states, however, that MMR vaccination may cause autism.
Before the vaccination, 2.6 million deaths from measles were caused globally
This myth was born in England in 1998. A scientist suggested a link between the MMR vaccine and autism and gastrointestinal disease. His pledge to stop distributing the MMR vaccine received much media attention. In 2004 it was discovered that the scientist had financial interests in making this claim.
A lawyer who intended to sue vaccine manufacturers hired him and recruited the children for the study. Moreover, the data was falsified: contrary to the reported onset of the symptoms after the vaccination, some of the children already showed symptoms before they were vaccinated. The original article was retracted by the journal.
The fears caused by the flawed information led to years of lowered vaccine uptake, with severe outbreaks as a consequence. As a second consequence, numerous independent studies were conducted in many parts of the world to test the relationship between the MMR vaccine and autism. All concluded that there is no such relationship.
Reasons why the myth is so persistent may be that the diagnosis of autism happens to fall into the period when, in most countries, MMR vaccination is recommended. This temporal contingency may give rise to a false sense of causality. Evidence shows that the MMR vaccination does not increase the risk of getting autism.
Despite the Global Measles and Rubella Strategic Plan 2012-2020, which set the ambitious goal of achieving measles and rubella elimination in at least five WHO regions by 2020, this is difficult to achieve. It is a misconception, however, that measles has been eliminated in Europe, and that therefore there is no reason to be vaccinated. Vaccination against measles helps protect the individual and others who may be not immune thanks to the so-called herd immunity: vaccination also stops the transmission of the disease and therefore indirectly protects non-immune individuals.
For measles, a 95 per cent vaccine coverage is needed for herd immunity to work. It is everyone’s responsibility to contribute to a safe and healthy environment for everyone.
The current situation in Malta is that we still have the elimination status for measles. After of number of years with no cases of measles, in 2018 we had five imported cases and one local transmission. This year, we have already seen over 15 locally acquired cases. Most of the cases occurred in adults who were not vaccinated.
We need to fast track our actions to ensure all ages have immunity to measles. International literature shows that people born before 1970 have been exposed to the highly circulating pathogen at the time and can be considered as immune. Those born after 1970 are recommended to check their records to see if they have had two doses of live measles-containing vaccine to be immune. If not vaccinated, it is recommended to visit the family doctor for advice.
European Immunisation Week held across Europe every year aims to raise awareness about the importance of vaccination. The slogan is ‘Prevent. Protect. Immunise’. This year’s campaign will also be used as an opportunity to celebrate everyday vaccine heroes.
These are the individuals who contribute to protecting lives through vaccination in so many ways – including researchers who develop safe and effective vaccines, policy-makers who make sure every child has equitable access to vaccines, health professionals who administer vaccines, parents who choose vaccination for their children, as well as everyone who seeks out and shares evidence-based information about vaccines.
Charmaine Gauci is Superintendent of Public Health.