By: Doyeun Park
As the number of coronavirus cases increases exponentially, people around the world are becoming more and more desperate for a vaccine. Since flu, measles, or chickenpox are so prevalent, it might be assumed that vaccines are easy to develop. In reality, vaccines take several years to make. For example, the modern form of the measles vaccine was developed in 8 years.
So, how are vaccines made?
In order to understand how vaccines are made, it’s important to learn how viruses affect our bodies. Viruses reproduce by injecting their genetic information into a host cell. Then, the host cell replicates about thousands of times, ultimately contaminating the body. In contrast, vaccines reproduce fewer than 20 times. Thus, it would not affect the body to the same extent. Moreover, vaccines for viruses produce “memory B cells” that protect against infection from the same strain in the future.
There are several strategies that vaccines employ to remove or deactivate harmful viruses. First, vaccines, such as those for polio, hepatitis B, influenza, and rabies, can deactivate viruses with a chemical. There are several benefits to this approach: it doesn’t create mild symptoms of the disease and is beneficial for people with weak immune systems. A drawback could include that one would require multiple doses to achieve immunity.
Another strategy is removing one part of the virus to be used as a vaccine. Vaccines such as hepatitis B, shingles vaccine, and HPV vaccines are made with this formula. These vaccines contain proteins that live on the surface of the virus. Similar to the aforementioned strategy, this type of vaccine is good for people with weakened immunity and persists in the body after two doses.
The third tactic is using bacteria. Some bacterias produce toxins that cause diseases. A few vaccines are made this way; the toxins inactivate the virus with a chemical called toxoid. Vaccines such as Haemophilus influenza type B, pneumococcal, and meningococcal vaccines are made this way.
Despite these promising strategies, it will take a long time to find the perfect vaccine. Scientists still need to explore potential side effects, cost-efficient strategies, and more. Furthermore, there are some ethical questions that arise with vaccines. One question might be who would receive the vaccine first? Should it cost money to administer or not?
With each passing day, the need for vaccines grows more dire. Scientists have made impressive progress on the vaccine, but it will take a while to perfect it. In fact, in an NPR article, it states that vaccines “may be only about 50% effective.” According to physician Bill Miller, he says that even though the vaccine may be only 50% effective, it may “reduce the severity of disease” in the 50% of people who are sick. With this note, researchers worldwide are currently aiming to find a more effective vaccine and make it upwards of 75% effective.
Sources:
https://www.chop.edu/centers-programs/vaccine-education-center/making-vaccines/how-are-vaccines-made