TIMELINE: Past to Present Coverage on COVID-19 Vaccine & Updates

What are vaccines?

A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism and is often made from weakened or killed forms of the microbe, its toxins, or one of its surface proteins. Vaccines are like a training course for the immune system. They prepare the body to fight disease without exposing it to disease symptoms.

How Vaccine Works?

1. Our immune system is composed of various types of cells. These cells defend us against invaders and remove harmful pathogens. Vaccination works by teaching our immune system how to recognise new diseases.
2. Vaccines stimulate our bodies to make antibodies against antigens of pathogens. It also teaches the immune system to remember the antigens that cause infection, which leads to a faster response to the same disease in the future.
3. In simple terms, vaccines work by exposing a person to a safer version of a disease. While the body responds to the vaccine, it builds an adaptive immune system, which helps the body to fight off the actual infection in the future.
4. When foreign invaders such as bacteria or viruses enter the body, immune cells called lymphocytes respond by producing antibodies, which are protein molecules. These antibodies fight the invader known as an antigen and protect against further infection.
5. After the threat has passed, many of the antibodies will break down, but immune cells called memory cells remain in the body. When the body encounters that antigen again, the memory cells produce antibodies fast and kill the harmful micro-organism.

Understand the phases/process of Vaccines development

Researchers and scientists would have taken years in Vaccine development in normal circumstances; however, it is only due to the emergency situation arising due to Corona Virus Pandemic. It is expected that a Vaccine would be developed within 4-5 months.

Phase 1 - It involves a basic understanding of the virus to identify the structure of proteins and genetics that make up the virus. It provides a basis for developing diagnostics kits and potential treatment options.

Phase-2 - It involves the identification of vaccine candidates by isolating the live virus before inactivating or weakening that can be used for immunity development.

Phase -3 - Pre-clinical testing: This is the stage before the vaccine can be tested on human, Vaccine is tested on the animals in this stage to see the response.

Phase -4 - Clinical trials: It involves testing on humans. There are 3 phases of clinical trials

1. Phase I of a clinical trial is conducted on small group of healthy individuals. It only indicates what is the ideal dose required to administer in the next stage, it provides evidence of the vaccine’s ability to generate an immune response and its safety.
   1. Vaccine is not considered safe if it develops any major complication, however little headache and fevers are expected.
2. In phase II, the range of participants is expanded to few hundred healthy participants to check the immune response system in the body and it also assesses the time period for which antibodies last to provide immunity against the virus.
3. Phase-III involves a very large group of people (Thousands of individuals) to investigate its efficiency among large population groups. Half of the population is administered the actual Vaccine and other half are administered dummy vaccines.
   1. Individuals administered Vaccines are checked on fixed intervals which can be months in normal conditions to see whether their immune system is responding to the virus or not.

Phase- 5: After Vaccine is successfully tested, it would require regulatory approval before it can be produced in bulk quantity.

Importance of Vaccine development for India

• India is the largest vaccine producing country in the world and if India is able to produce an indigenous vaccine, it will help in matching the demand in time, which otherwise would not have been possible for one more year.
• India is one of the most affected countries due to COVID, it would have to wait for a long time if it was not being developed indigenously. Once the trials are done, Bharat Biotech will be targeting a manufacturing capacity of 300 million doses.
• Approximately 70 per cent of vaccines for low- and middle-income countries are manufactured in India and delivered through partnerships with UNICEF and Gavi. Vaccine development in India ensures the availability of affordable vaccines.

What are the challenges across distribution of COVID-19 vaccine?

• Priority– Within the country, it is certainly not clear who should be treated first or it should be determined by need, affordability, vulnerability or some other criterion or a combination of all.
• Guideline– The need of a policy regarding how much of the vaccine produced should go to other countries and at what cost. It must ensure whether agencies funding the research or the researchers or government authorities or citizens decide on a global policy of distribution.
• Adult Vaccination program: mass-scale immunization programs aimed at the adult population does not have much awareness right now. Vaccination is currently limited to children and pregnant women
• Distributive hierarchy–The cost of the vaccine and its possible loss will have to be borne by the last receiver which likely to be more needy people of the society.
• Cost– If open market forces determine the cost of the vaccine and affordability then, the section of society most vulnerable to the disease would get left out. Affordable prices ensure that more people around the globe have access to these life-saving tools.
• Post-Vaccination antibody tests: Even if the immunization is done on a mass level, there will be a requirement for reliable anti-body tests that can provide the right info on the impacts of Vaccination. Presently available anti-body tests are unreliable.