“The World Health Organization estimates that vaccines prevented at least 10 million deaths in just five years between 2010 and 2015. It says vaccines have been one of the biggest success stories of modern medicine.” – BBC, June 2019
“The World Health Organization (WHO) recently listed vaccine hesitancy as one of their top 10 biggest threats to global health.” – NHS, July 2019 (last review)
Vaccination is one of the most effective means of preventing disease. It works by helping the body’s natural immune system to learn about, remember and later on recognise and respond to potential pathogens, on exposure. In order to do this, a safe, non-infectious form of the disease-causing viruses, bacteria or toxins produced by bacteria need to be introduced to the body first. This may be done in the form of:
- Live attenuated vaccines – weakened form of the virus/bacterium (e.g. chickenpox, smallpox, rotavirus and MMR vaccines)
- Inactivated vaccines – killed form of the virus/bacterium (e.g. hepatitis A, polio, rabies. influenza vaccines)
- Toxoid vaccines – pathogenic toxins produced by some bacteria (e.g. tetanus, diphtheria vaccines)
- Subunit / conjugate / recombinant / polysaccharide vaccines – specific part of the pathogen such as a protein or capsid (e.g. hepatitis B, HPV, shingles vaccines)
Which form of vaccination is developed against a specific disease is determined by how the body’s immune system reacts to a given form. The idea is to prompt the immune system to produce antibodies against the vaccine and store these antibodies and information about the pathogenic origin of the vaccine in its memory. This way, if real-life exposure to the said pathogen does occur later on, the body is prepared and ready to fight the pathogen off immediately. This would effectively help to prevent disease caused by the pathogen – or in other cases, at least reduce the impact of infection.
Some vaccines require one or two booster doses later on, in order to (what I would call) ‘remind’ the immune system of their existence and how to tackle their respective pathogen.
Herd immunity is a phenomenon that arises when immunity against a particular disease is indirectly created within a community when a sufficient percentage of the population is vaccinated. The WHO’s target proportion for herd immunity against highly infectious disease is 95%.
An infectious disease may be declared as eliminated from a country or zone if an effective vaccination program establishes sufficient herd immunity. The WHO defines this as the absence of endemic transmission in a defined geographic area for at least 12 months, in the presence of a well-performing surveillance system.
Below is a compilation of vaccinations for children from birth to 6 years recommended by the World Health Organisation (WHO) and the Center for Disease Control and Prevention (CDC) (adapted from CDC’s website – https://www.cdc.gov/vaccines/schedules/easy-to-read/child-easyread.html).
In addition, there are other recommended or mandatory vaccines for people traveling to certain regions of the world where there may be endemic diseases, as well as for people working in the health profession.
Vaccine hesitancy refers to the scenario where people with access to vaccination refuse, or sometimes delay, getting themselves or their children vaccinated.
This phenomenon has led to the formation of a sort of ‘cult’ known as anti-vaxxers, who practise and encourage vaccine hesitancy and protest against vaccination. They believe that vaccination is an unnecessary evil that should not be imposed on people, and that it should be the right of every individual to decide on whether they want to have themselves of their children vaccinated.
Let’s take a look at some of the reasons that have bred a community of anti-vaxxers over the decades, along with some facts and figures. MMR and Influenza vaccines have been used for the purpose of discussion – however, the impact of vaccines developed against many other diseases, some of which have been eliminated in different parts of the world, are not to be disregarded.
Following are a few tables drawn up using data published by Public Health England, CDC and news publications.
Religion seems to play a significant role in vaccine hesitancy around the world. In both the UK and the USA, the recent and ongoing measles outbreaks mentioned in Table 1 were in predominantly Orthodox Jewish neighbourhoods. While most Orthodox Jews – including rabbis – increasingly encourage vaccination, there still remains a faction of those who strongly condemn it and impose vaccine hesitancy on their communities due to underlying fears and conspiracy theories. They claim that vaccination is an intended method of holocaust-like mass extinction, or a conspiracy by the CDC and global pharmaceutical companies to carry out unsafe human testing, and a long-term plan designed to make themselves a fortune.
Yet, a vast majority of cases in these outbreaks are found to be among unvaccinated individuals. Spread of disease is aided too by the close-knit and interactive lifestyle of these communities, as well as their frequent travel to and from Israel. In fact, the 2018 measles outbreaks in the USA were found to be associated with travellers coming back from Israel, where there was a large outbreak ongoing. Needless to say, this has fuelled the unfortunate additional issue of anti-Semitism among the rest of the population affected by these outbreaks.
Religious influence is true in other faiths as well, as vaccines which have gelatin, which is of porcine (pig) origin, are considered to be unclean (non-Halal) among Muslims. Jews are also sometimes weary of such vaccines. Again, conspiracy theories such as vaccination being a method of mass extinction are sometimes spread by radical Muslim clerics, strongly condemning – and, in extreme cases, violently threatening – the support and use of vaccination.
A few radical Christian groups, too, oppose vaccination. They believe that humans are created by God to endure whatever comes their way and should accept suffering and death as they come – rather than introduce foreign, man-made substances into their bodies and obstruct the ‘plan’ intended for them.
Misinformation or publication of false information is just as big an influence on vaccine hesitancy. Take, for example, the ongoing outbreak of mumps in the UK (Table 2). This outbreak has mostly affected youth, who were unvaccinated children in the late 90’s. This was a result of fear and anger injected into the people by a paper published by Andrew Wakefield in 1998, wrongly associating the MMR vaccine with the incidence of autism in children. (Autism is a developmental disorder which TBL hopes to explore in a later article.) This was later proven to be gravely incorrect and it was found that Wakefield had used an extremely small sample size of 12 cases that had been picked for reasons that were monetary and of conflicting interest. Wakefield, who was a practising physician in the UK, was barred from practice and fled to the US, where he gathered and nurtured another following of anti-vaxxers.
Contrary to Wakefield’s misleading publication, Tables 1 and 3 show how measles and rubella incidence were effectively reduced after the introduction of vaccines against them. However, the repercussions of that false publication are present and evident today as it caused a drop of MMR vaccination in the UK from 90% to 79% or lower at the time, and an entire population is now suffering the consequences. Ironically, autism incidence continues to prevail among children of non-vaccinated mothers.
- Lack of Awareness
While the vaccines administered to infants and children may be brought to a new parent’s attention by the healthcare system, there are many other vaccines that are situation-based and are not necessarily known to everyone. For instance, there are specific recommended vaccines to be taken (or to have been administered within two years before intended visit) prior to traveling to different countries or regions. Unless mandatory, these may sometimes be overlooked as unnecessary, or may even go unheard of completely.
There are also vaccines such as the HPV vaccine which was introduced in more recent years, and so may not have been given to females who were who were born in earlier decades – girls in their 20’s and beyond who have not received this vaccine should be advised to do so.
There is also the seasonal flu vaccine – an annual vaccine that is developed based on the strain of influenza that is present in that particular year. Table 4 shows that millions of cases and deaths due to influenza infection are averted every year. Fluctuation of figures may occur due to a few reasons including the resistance strength of the strain in that particular year as well as varying vaccination coverage or access in a particular country or geographic area.
These are but a few arguments used by anti-vaxxers in their campaign to make the world vaccine-free. However, facts and figures in scientific research have shown that there is an undeniable positive impact of vaccination on global health and immunity as a whole. The bottom-line is, while there might be a minimal risk of complication or allergic reaction to certain vaccines in a handful of recipients – as with any treatment or medication that may be administered to a patient – these are few and far between. This is why discussion with a GP prior to vaccination is very important, particularly with pregnant, immunocompromised and elderly individuals. The proven benefit of vaccination to the individual’s and community’s well-being should be reason enough for each of us to be vaccine-aware and up-to-date with our jabs.
Cover illustration from Pixta.