World Immunization Week 2021
This year, as we are in a period of time where the vaccine for the Corona Virus has been found, and immense exposure and importance is being given to that, the World Health Organization has come up with the theme, ‘Vaccines bring us closer’ which is in theory very true.
In a world where people are asked to keep a safe distance from everyone, in a world where shaking hands and hugging are looked at as luxuries, herd immunity is something that can bring us closer.

What is Herd Immunity?
As suggested by the term itself, it is when the spread of a disease: either bacterial or viral is stopped due to an internal force from the herd or the community. For instance, if there were 100 people in a room and only 50% of them were vaccinated against a certain disease, the addition of 1 infected person can in turn affect 50 others, who are not vaccinated. However, if all 100 people (100%) are vaccinated, then even though one infected person enters the room, the disease is not set to spread. Although a 100% rate is slightly unrealistic, many countries focus on achieving at least a 75% herd immunity, so that they are better equipped to treat the 25% who cannot be immunized and therefore will require extensive medical attention in case an infected person enters the community.
What Does the World Health Organization Aim to Achieve this Year?
As part of this year’s campaign, WHO along with their partners hope to increase the trust and confidence in vaccines, and increase the acceptance of vaccines whilst also encouraging more investors to invest in the development and manufacturing of these vaccines, so that they could increase routine immunization and eradicate barriers to accessing vaccines.

Importance of Being Vaccinated
Immunization is simply not a means of protecting yourself and those around you, being immune to a disease and therefore not being affected by it can further help nations and future generations. How? Well, not too long ago there were 1000s of people dying due to tetanus, diphtheria and whooping cough. However, that is not the case today, as kids are being vaccinated against these diseases at a very young age, therefore the microbes do not have the capability to infect individuals. This eventually results in it being scarce or completely eliminated. We are literally one shot away from eliminating extremely dangerous and infectious diseases. What’s stopping you?
For many, it is the lack of information. They do not know what a vaccine is or how it helps build up one’s immunity. Here’s a crash course.
How do Vaccines Build Immunity?
A vaccine consists of a weaker, more inactive form of the microbe (bacteria, virus) along with a protein called the antigen that acts as an Identification Card for the microbe. Hence, when injected into the body, our immune system begins producing macrophages, B-Cells and T-Cells to fight the infection. The macrophages eat up the microbe, identify the antigen and take this identifier, also known as an MHC to the cell surface of the T-Cell, where it locks into the cell and then stimulates the B-Cell to produce an antibody (molecule to fight the infection). These cells also have memory cells, which remember what antibody needs to be created for a specific antigen. So in the instance that someone who is vaccinated gets infected by the microbe, their immune system can react faster and defeat the infection. Although, this is a very layman way of explaining what happens, this gives individuals a rough idea as to what happens within their bodies after a vaccine.
Busting Famous Myths About Vaccines
- Vaccines cause autism: The general public began to fear vaccination due to its association with autism after a study that was published in 1970, over which the author said he had a financial incentive for the study to be published. That study has been debunked by many other studies that used larger groups of children as subjects.
- Vaccines do not cause the diseases they wish to prevent, rather they mimic the disease so that our bodies can create the required antibodies to fight it, in case the real more severe disease, presents itself.
- Parents usually believe that it is not necessary to vaccinate their children so early in life, however, that isn’t the case as vaccinating kids could help prevent serious illnesses such as diphtheria, whooping cough and tetanus
- Not vaccinating my child, only affects my child: Not getting vaccinated is like failing to stop at a four-way intersection, if three people stop and one doesn’t, the risk of an accident is relatively small. If two or three people don’t stop, the risk is much higher to everyone at the intersection.

Immunization in Sri Lanka
Sri Lanka’s immunization journey began in 1886 with the vaccination for smallpox. With the establishment of the Family Health Bureau (FHB) under the Ministry of Health in 1961, Sri Lanka has sought to reduce the child mortality rate by introducing triple vaccination against diphtheria, pertussis, and tetanus. Then in 1962 the oral polio vaccine was introduced, followed by the BCG vaccine in 1963 and tetanus toxoid to expectant mothers in 1969.
As of today, Sri Lankans are vaccinated against tuberculosis, hepatitis B, diphtheria, pertussis, tetanus, haemophilus, influenzae type B, measles, mumps, rubella, meningococci, hepatitis A, varicella, rotavirus and the human papilloma virus.
According to the WHO, Sri Lanka has eradicated polio (in 2014), measles (in 2019), rubella and Congenital Rubella Syndrome (in 2020), and mother-to-child HIV transmission (in 2020).
References:
- World Health Organization (Immunization Week 2021): https://www.who.int/news-room/events/detail/2021/04/24/default-calendar/world-immunization-week-2021#:~:text=Using%20the%20theme%20’Vaccines%20bring,of%20everyone%2C%20everywhere%20throughout%20life.
- Herd Immunity Illustration: https://www.gavi.org/sites/default/files/vaccineswork/2020/Herd-immunity.pdf
- Myths about Vaccinations: https://www.rush.edu/news/7-myths-about-vaccines
- Immunization in Sri Lanka: https://www.epid.gov.lk/web/index.php?option=com_content&view=article&id=154&Itemid=481&lang=en
- SLMA Guidelines and Information on Vaccines: https://slma.lk/wp-content/uploads/2017/12/GSK-SLMA-Guidelines-Information-on-Vaccines.pdf
- Sri Lanka Journal of Child Health: https://sljch.sljol.info/articles/10.4038/sljch.v49i4.9260/galley/6878/download