If you’ve been watching the news, you’ve probably heard of several companies who are working on developing COVID-19 vaccines. The biggest names in the game have been Pfizer and its partner BioNTech, Moderna, and AstraZeneca and its partner the University of Oxford.
But those are just some of many dozens of vaccines in development in multiple countries worldwide. Just because a few are being approved now doesn’t stop the process of the others still in development.
But why would we need so many different vaccines, and what makes them different from each other? Here are the answers to those questions.
Transportation and Storage Temperature Requirements
There’s a lot that goes into the vaccination process well before it actually reaches the arms of the public.
Vaccines are fragile and must be stored at specific temperatures to keep them effective. Too cold and the vaccine might freeze and cause the ingredients to be damaged. Too hot and the components might become inactivated.
This becomes a problem if we aren’t able to properly transport or store a vaccine, because its temperature requirements are unusual, as in the case of the Pfizer vaccine. This particular vaccine has to be kept at -70 degrees Celsius, which is a temperature that you can only reach with expensive specialized freezers that are in high demand and low supply.
For rural areas or developing countries and even for many of our hospitals and clinics in the United States, those specialized freezers are unrealistic. Additionally, getting those vaccines to the freezers is another challenge when the vaccine has to sit on a plane or truck for hours at a time.
Other vaccines, like Modern’s and AstraZeneca/Oxford’s vaccines, don’t have a stringent temperature requirement, which makes them much more accessible for everyone. It’s easier to transport and store them using normal vaccine standards and equipment, and that makes it easier to get them to people who need them, wherever they might be.
How the Vaccine Works
There are multiple ways you can make a vaccine. Both the Pfizer/BioNTech and Moderna vaccines use new biotechnology called mRNA, which has been used primarily in developing cancer therapies and treatments.
This type of vaccine works by giving your cells an mRNA template to make a protein that’s specific to the coronavirus that causes COVID-19. Your cells make the protein, and your immune system then learns to respond to that protein and make antibodies.
Because your immune system has a memory, it can now remember how to quickly and effectively respond when it comes across those proteins again. Your body gets rid of the mRNA once it’s been used, and the proteins are unable to form the virus that would make you sick.
The more traditional way of making a vaccine is to use a live or inactivated virus, just enough to trigger an appropriate immune response.
AstraZeneca/Oxford’s vaccine uses a modified virus that normally causes colds in chimpanzees but is harmless to humans. The modified virus carries the same protein as the COVID-19 virus, but because it’s a chimpanzee virus, it won’t get you sick with COVID-19 while it trains your immune system to respond to the coronavirus.
Since we’re still learning about the long-term effects of COVID-19 as well as how long immunity lasts after getting sick or vaccinated, having multiple types of vaccines means we can more quickly figure out which ones work better to grant longer-lasting immunity.
Different vaccines will also use different ingredients. That’s good news to people who might be allergic to ingredients in one vaccine but not to ingredients in another.
How the Vaccine is Administered
Most people are familiar with vaccines as injections that you get in your upper arm. But that can be stressful or not a preferred route for many patients for many reasons, and over time, we’ve come up with other ways of giving vaccines.
Intranasal vaccines are a vaccine option currently in development for COVID-19. However, these vaccines are still in the beginning stages of clinical trials, and it’ll be a while until they’re widely available to the public.
Until then, intramuscular injections are the most effective way to get the vaccine and begin developing herd immunity in the public to protect those who might not be able to get an injected vaccine and are waiting for the intranasal option.
Costs and Availability
Vaccine development is not cheap, and neither is the manufacturing, transportation, storage, and administration of the vaccines once they’re approved for public use.
Just as in any part of the free market, competition can help regulate prices and prevent one company from having a monopoly on the market.
Some vaccines are also just frankly cheaper than others because they use more readily available ingredients and have less stringent storage and transportation requirements.
Having multiple vaccines also increases the overall availability of vaccines. Each company is limited in how much it can produce at one time, so multiple companies producing millions of doses at the same time will only speed up distribution and increase the availability of the vaccines to the public.
It’s a Good Thing
Each vaccine is a little bit different, even the ones that use the same technology.
Having multiple vaccines for any disease is a good thing for us. Not only does it prevent one company from having a monopoly, but it increases availability, not only in the number of doses available, but in the means of storage, transportation, and accessibility.