Covid-19 pandemic has opened a new window to work on different kinds of vaccines globally. This is the result now there are about 5 kinds of Covid-19 vaccines in different stages of development. The quality and Standards maintained by the Indian Scientific Institutions are now rated top in the world. Thanks to Bharat Bio Tech which is now coming forward for the release of the vaccine at an affordable price.
The different kinds of Vaccines are
1. m-RNA Vaccine: A vaccine developed by Pfizer and BioN tech.
In the case of Sars-CoV-2, RNA vaccines contain the genetic code for the characteristic spike protein of the virus. When they are injected into our bodies, our cells read the code, and produce and present the spike protein to our immune system. Our immune system then reacts and develops memory immune cells to respond specifically to the Sars-CoV-2 spike protein. The memory immune cells will be quickly activated to shut down infection and prevent us from getting Covid-19. Such vaccines contain only the spike gene of the virus, but lack the other Sars-CoV-2 genes required to generate new viruses, so vaccination will not cause the virus to spread in the body or make a person infectious. The vaccines, however, will very likely remain effective against the many mutations of the virus because the immune system is able to recognise and target many different parts of the spike protein. Although RNA vaccines have not been licensed for use in humans previously, they have been tested in clinical trials with excellent safety profiles so far.
Many commonly used vaccines also contain RNA. Live viral vaccines, such as the yellow fever vaccine – arguably the best vaccine in the world today, along with measles, mumps and rubella vaccines – all contain viral RNA. Despite that, these vaccines are among the safest and most effective vaccines in the world.
Systemic side effects, such as headache and low-grade fever, are also common following vaccinations. This is mostly caused by our immune response. Our immune cells talk to one another by secreting chemicals. These naturally produced chemicals, besides shaping the immune response, do also have unintended effects. A common one that we all encounter when our immune system responds to a viral infection is the metallic taste in our mouths. However, all these side effects are mild.
It is important to note that these side effects have come from phase one trials, which test a range of doses to find the highest vaccine dose that can be given to maximise immune response while keeping side effects tolerable.
In contrast, a Phase 3 trial would test only a fixed dose that balances the benefit of immunisation while minimising side effects.
2. Live Attenuated Virus Vaccine: Vaccines are prepared by weakened live viruses. This vaccine gives life time protection by taking two shots second shot is a booster dose. The Bharat Bio tech is developing the vaccine on this principle as Covaxin.
An attenuated vaccine (or a live attenuated vaccine) is a vaccine created by reducing the virulence of a pathogen, but still keeping it viable (or “live”).Attenuation takes an infectious agent and alters it so that it becomes harmless or less virulent. These vaccines contrast to those produced by “killing” the virus (inactivated vaccine).
An inactivated vaccine (or killed vaccine) is a vaccine consisting of virus particles, bacteria, or other pathogens that have been grown in culture and then lose disease producing capacity. In contrast, live vaccines use pathogens that are still alive (but are almost always attenuated, that is, weakened). Pathogens for inactivated vaccines are grown under controlled conditions and are killed as a means to reduce infectivity (virulence) and thus prevent infection from the vaccine. The virus is killed using a method such as heat or formaldehyde.
3. Virus vector: These Vaccines boost the immune system and pave way for disease resistance.
Viral vectors are tools commonly used by molecular biologists to deliver genetic material into cells. This process can be performed inside a living organism (in vivo) or in cell culture (in vitro). Viruses have evolved specialized molecular mechanisms to efficiently transport their genomes inside the cells they infect. Delivery of genes, or other genetic material, by a vector is termed transduction and the infected cells are described as transduced. Molecular biologists first harnessed this machinery in the 1970s. Paul Berg used a modified SV40 virus containing DNA from the bacteriophage λ to infect monkey kidney cells maintained in culture.
In addition to their use in molecular biology research, viral vectors are used for gene therapy and the development of vaccines.
4. An inactivated vaccine (or killed vaccine) is a vaccine consisting of virus particles, bacteria, or other pathogens that have been grown in culture and then lose disease producing capacity. In contrast, live vaccines use pathogens that are still alive (but are almost always attenuated, that is, weakened). Pathogens for inactivated vaccines are grown under controlled conditions and are killed as a means to reduce infectivity (virulence) and thus prevent infection from the vaccine. The virus is killed using a method such as heat or formaldehyde. These vaccines are not that much effective when compared to the live virus and vaccine requires booster dosage after some time
5. Component vaccine: These vaccines are prepared with virus protein ,protective caps of the virus. Since these vaccines are prepared with the infection causing parts of the virus, they produce very strong antibodies that show disease resistance in the body, these are suitable for everyone but requires booster shots.
An example of component vaccine is found in Australian vaccine which has been given to patients and antibodies against single component was found in patients in their trials so it is temporally stopped.
India is in forefront in releasing Quality Vaccine Candidates in The World
Now the Entire World is looking after India for a quality and with more efficacy
Vaccines.
