This post was written by Nikhil Mankuzhy, third year medical student from Oakland University William Beaumont School of Medicine
Vaccination is thought to prevent 2-3 million deaths in the world each year and is considered the most effective way to prevent infectious disease. COVID-19, the disease caused by the new coronavirus, has become a global pandemic and there is no vaccine available…at least, not yet.
Vaccines work by helping a person’s body to build up its immune system (which is the body’s natural defense) to prevent infection. The immune system is made up of infection fighting cells called white blood cells and proteins that fight against germs called antibodies. Vaccines expose the body to a part of the virus or bacteria without causing the person receiving the vaccine to get sick. Instead, it causes the body to increase its immune response. This means making more white blood cells and antibodies that can target the invading germ. After building this response, the immune system remembers the target. When a person is exposed to the real germ, it can get rid of it before it causes an infection. However, this process can take weeks and sometimes takes more than one dose of the vaccine.
Since vaccines involve injecting something into the body, the testing process is taken very seriously. There are a lot of steps needed to make sure a vaccine is both effective and safe. This includes:
- Pre-clinical phase: Scientists work in the laboratory to test a possible vaccine under the microscope and in animals.
- Phase I trial: This is the first step of testing in humans, where the vaccine is given to a small group of healthy adult volunteers to see if it is safe and if it produces an immune response.
- Phase II trial: A larger group of over 100 people are given the vaccine to check the safety and immune system’s response, but also figure out the best way to give the vaccine, and how often.
- Phase III trial: This is the last step before submitting the vaccine for FDA approval. Testing is done in thousands of people, to see if there are any rare side effects, and importantly, see if it works to prevent the infection.
So, what does this mean for COVID-19? Well, because scientists were already trying to develop a vaccine for the coronavirus that causes Middle East Respiratory Syndrome (MERS), they had a head start on making one for the new coronavirus that causes COVID-19. In-fact, testing of possible vaccines for COVID-19 has begun faster than ever before. Multiple organizations are working together to help the vaccine progress with the least amount of delays. Still, a fully tested and approved vaccine will likely not be widely available until at least 2021.
Until then, the best way to prevent getting COVID-19 is to avoid being exposed to the virus by social distancing. The CDC also now recommends wearing a cloth face cover over the mouth and nose when in public. These steps are extremely important to slow the pandemic while we wait for a vaccine to become available.