At the time of writing this blog post, 68.9% of people in the US have received at least 1 vaccine dose and 59.2% of people in the US are fully vaccinated. People have been wondering how effective the vaccine is and whether it’s even worth getting. To understand how some vaccines can be more effective than others, we must first understand how vaccines are made.

A basic summary of the vaccine manufacturing process

There are two main ways of manufacturing vaccines: The first method weakens the virus so it cannot reproduce at high rates when inserted into the body. The second method completely inactivates the virus by killing it with a chemical. Weakening the virus is beneficial because it provides immunity that is usually lifelong. However, it cannot be administered to patients with weak immune systems. Completely killing the virus allows the virus to do no harm, but since the body has still “seen” the virus, the body knows how to fight the virus. The only disadvantage to this method is that several doses are required to achieve the same effect as a weakened virus vaccine.

How does this apply to COVID-19 vaccines?

Pfizer and Moderna’s COVID-19 vaccine is an mRNA vaccine. COVID-19’s mRNA function as a blueprint for the manufacturing of a COVID-19 virus protein. The human body is predisposed to automatically creating proteins once it is provided with mRNA, so, naturally, the mRNA is assembled into a COVID-19 protein. The immune system quickly realizes that the protein is foreign and has the potential to do harm, so it creates an immune response that is memorized. When the body is exposed to the real virus, the immune system is already prepared and can effectively combat the virus.

Johnson & Johnson and the AstraZeneca vaccines are vector virus vaccines. The gene that codes for the coronavirus protein is put into a virus that cannot reproduce by itself but can enter cells and deliver the gene. This type of vaccine is engineered to not cause the disease, so it can be given to people with weak immune systems.