Immunity and Vaccination

For Shruti and Rohan, not vaccinating their child had been a conscious decision. They were among that group of new-age couples who believed a child’s immunity needs to be built naturally. So they had over-ridden the Doctor’s advice. It was a decision that came back to haunt them when their 2-year-old son came down with a bad bout of diarhhoea accompanied by vomiting. When medications prescribed by their son’s paediatrician made no difference and he became unresponsive, the panicked couple rushed him to the Emergency. They were told their son was suffering from rotavirus, a common ailment in children that could be fatal. Rotavirus is a vaccine-preventable disease.

Immunizations currently prevent 2 million to 3 million deaths every year. Yet, more than 1.5 million people worldwide die from vaccine-preventable diseases.

Are Immunization & Vaccination the same thing?

As per WHO (World Health Organization), immunization is the procedure by which an individual is made resistant or immune to a disease by administrating a vaccine. The vaccine stimulates the body’s immunity to keep a person protected against subsequent infections or diseases.

An individual gains immunity when the body has been exposed to the disease through either vaccination or illness. Once exposed, your immune system generates antibodies so that the disease cannot affect you the second time.

Vaccines: How do they work?

Vaccines help the immune system counter infections faster and in a more effective manner. When you are vaccinated, it sparks the immune response, thus helping the body to fight off and remember the virus so that it can attack it in the event of a future invasion. As vaccines are prepared from a small amount of dead or weak germs, they are unlikely to make you fall sick. Vaccines provide long-term immunity to certain diseases without the risk of adverse side effects.

What is in a vaccine?

All ingredients used in the preparation of a vaccine have a pivotal role to play in ensuring their safety and effectiveness. These include the following:

• The antigen – a weakened or killed form of a bacteria or virus that trains the body to identify and fight diseases if we encounter those later in life
• Adjuvants that help boost immune responses
• Preservatives to ensure that a vaccine remains effective for the desired period
• Stabilizers that protect vaccines during transportation and storage

Vaccine ingredients may not look familiar when listed on the labels. Many of these used components occur in the environment, in our bodies, and in the foods we consume. In addition to the ingredients, the vaccine itself is thoroughly monitored and tested to ensure safety.

Natural Immunity V/s Immunity Following a Vaccine

Vaccines are safer. A person develops natural immunity after getting sick with a disease. However, diseases may be serious, sometimes potentially fatal. A vaccine safeguards you against a disease before you get infected by it.

Herd Immunity

When a high percentage of the population is vaccinated, it is difficult for infectious diseases to spread, because there are not many people who can be infected. For instance, if someone with measles is surrounded by people who also are vaccinated against the disease, measles cannot easily be passed on to those around. This is known as ‘herd immunity’ or ‘community immunity’ or ‘herd protection’. It offers protection to vulnerable populations, such as newborns, elderly people, and those who are too sick and cannot be vaccinated.

Herd immunity, however, does not provide protection against all vaccine-preventable diseases. An example of this is tetanus, which spreads from bacteria found in the environment and not from people who suffer from the disease. In such a case, no matter how many individuals around you get vaccinated against the disease, it will not protect you until you get vaccinated.

What are the diseases vaccines can prevent?

As parents, you can protect your children from these 14 vaccine-preventable infections/diseases before they turn 2 year-old:

1. 1. Hepatitis A
2. 2. Hepatitis B (Hib)
3. 3. Diphtheria
4. 4. Hemophilus influenzae type b (Hib)
5. 5. Mumps
6. 6. Measles
7. 7. Influenza (flu)
8. 8. Polio
9. 9. Pneumococcal disease
10. 10. Pertussis (Whooping cough)
11. 11. Rotavirus
12. 12. Rubella (German measles)
13. 13. Varicella (chickenpox)
14. 14. Tetanus (lockjaw)

What vaccines do adults need?

Adults must keep up with their vaccinations because in due course of time, immunity from childhood vaccines may wear off. They are also at a higher risk for other diseases. Vaccination is among the safest and most convenient preventive measures.

The vaccines you need as an adult are determined by factors, including your age, lifestyle, health condition, and which vaccines you have already received during your life. As an adult, vaccines are generally recommended for protection against:

• Seasonal influenza (flu)
• Pertussis, also known as whooping cough
• Tetanus and diphtheria
• Shingles
• Pneumococcal diseases

Still have questions about vaccination? Find out what you should do?

If you still have questions about vaccines, talk to your healthcare worker. He/she can provide you with evidence-based advice about vaccination for you and your children, including the recommended vaccination schedule prevalent in your country.