A covid vaccine is a vaccine which provides immunity against severe acute respiratory syndrome corona virus 2, the virus that causes corona virus disease. They are used to reduce the spread and death caused by covid-19. Corona virus causes diseases like severe acute respiratory syndrome (SARS) and Middle east respiratory syndrome (MERS). It was the need to develop various vaccine technologies during early 2020.
There are four main types of covid vaccines:
1 Whole virus
Many vaccines use whole viruses to cause an immune response.
There are two main approaches;
- Live attenuated vaccines use a weakened form of the virus that can still reproduce without causing illness
- Inactivated vaccines use viruses whose genetic material has been destroyed so they cannot reproduce, but can still cause an immune response
Both types use well-established technology and methods for regulatory approval, but live attenuated ones may risk causing disease in people with weak immune systems and it requires to be stored in cold storage, to use in less developed countries.
2 Protein subunit
Subunit vaccines use pieces of the pathogen often fragments of protein to trigger an immune response. It minimizes the risk of side effects, but the immune response may be weaker. This is why it often requires help, to increase the immune response. Its example can be an existing subunit vaccine is the hepatitis B vaccine.
3 Nucleic acid
Nucleic acid vaccines use genetic material either RNA or DNA, it provides cells with the instructions to make the antigen. In the case of covid-19, this is the important protein. Once this genetic material gets into human cells, it uses the cell’s protein factories to make the antigen that will cause an immune response. The advantages of this vaccine are that they are easy to make and cheap. Since the antigen is produced inside its own cells and in large quantities, the immune reaction is strong. RNA vaccines need to be kept at ultra cold temperatures, -70C or lower, which could prove challenging for countries that don’t have specialized cold storage equipment, specially low and middle income countries.
4 Viral vector
The viral vector vaccine works by giving cells genetic instruction to produce antigens. But they are different from nucleic acid vaccines in which they use a harmless virus, different from the vaccine which is targeting to deliver these instructions into the cell. This type of vaccine causes the common cold as well. With nucleic acid vaccines, the body’s own cellular machinery is taken to produce the antigen from those instructions, in order to cause an immune response. Viral vector vaccines can copy natural viral infection and should therefore cause a strong immune response. There is a chance that many people may get the virus again, and some may be immune to it.
Benefits of covid vaccine
- Covid vaccine can keep people from getting and spreading Covid-19
- Covid vaccines also keep people from getting seriously ill even if they do get covid-19
- Getting vaccinated protects people around you, particularly people at increased risk for severe illness from Covid-19
- Once you are fully vaccinated, you can start doing more work in crowd
- After being vaccinated for Covid-19 one can resume many activities that one did before the pandemic
- One can do work without wearing a mask or staying six feet apart
- Covid vaccine is a safer way to help build protection
- Covid vaccine helps in protection in people who have recovered from Covid-19
Covid vaccine side effects
It is normal to have some light side effects after the vaccine. It means that the vaccine is preparing the body’s immune system to protect itself from the disease, however, not everyone gets them. Most of these are short term side effects.
They may include the following;
- Having a painful and heavy feeling in the arm where one had injected the injection
- Headache or muscle ache
- joint pain
- Nausea or vomiting
- Feeling tired