Comparing COVID vaccines

Graphic by Astrid Hernandez | Mercury Staff

As the Pfizer and Moderna vaccines increase in distribution, possible side effects and storage obstacles raise potential concerns.

On Dec. 11, 2020, the Pfizer/BioNTech vaccine was approved and became the first vaccine administered to prevent COVID-19.  Just seven days later, the U.S Food and Drug Administration approved the second vaccine, Moderna. According to the University of Oxford, approximately 3.8 million people in the United States have received a vaccine thus far.

While both vaccines were approved by the U.S. Food and Drug Administration, both major and minor side effects have taken effect. The vaccines may pose a threat to elderly patients and individuals who are allergic to ingredients found in the vaccine. Following the death of 23 vaccinated individuals in Norway, the Norwegian Institute of Public Health changed its COVID-19 vaccination policy to acknowledge the threat the Pfizer vaccine may pose to the elderly and immunocompromised.

According to The New York Times, two healthcare workers in Alaska experienced an anaphylactic shock after receiving the Pfizer vaccine’s first dose. Similarly, the Bay Area News Group reported that a high number of people experienced an anaphylactic shock after receiving a dose of the Moderna vaccine in San Diego, California. Nikhil Bhayani, an infectious disease specialist in the North Texas area, shared what he knew about the potential side effects of the COVID-19 vaccine.

“Most likely, the 23 deaths in Norway happened because they were allergic to an ingredient in the vaccine called polyethylene glycol,” Bhayani said.

Yet, the Centers for Disease Control and Prevention has stated that minor side effects after receiving a dosage of the vaccine are normal and signals that your body is building immunity against the COVID-19 virus.

“The most common symptoms for patients who have been vaccinated are fevers, headaches, fatigue, malaise,” Bhayani said. “Some people have had rashes or large lymph nodes, but all of that usually subsides within the first 24 hours.”

UT Southwestern’s Infectious Disease Specialist, Julie Trivedi, said that if a patient has a history of allergies or reactions to previous vaccines, it would be worth checking with their primary care doctor or an immunology specialist before getting vaccinated. Trivedi said that while research has been conducted, there is still much unknown about the vaccine’s side effects.

“This is the first time mRNA vaccines have been rolled out, so the technology has been around for a while. I think this is where people have concerns thinking, ah, will this change my DNA or cause any other harm?” Trivedi said. “There’s so much we do not know about vaccines or drugs until several years after the product.”

In terms of efficacy, the Pfizer vaccine has an efficacy rate of 95%, while the Moderna vaccine has an efficacy rate of 94.1%. However, they differ primarily in the time interval between both doses and the minimum age group the vaccine can be administered. According to the UT Southwestern Science Review Committee, the Pfizer vaccine’s second dose is given 21 days after the first dose and is administered to ages sixteen and above. In comparison, the Moderna vaccine is given 28 days after the first dose and is administered to ages eighteen and above.

When it comes to vaccine accessibility, storage and transportation play an integral role. The Pfizer vaccine needs to be stored at a temperature of -80 degrees Celsius and transported up to 15 days in a thermal shipping box. The vaccine can only be stored in a refrigerator for five days. In contrast, Moderna requires storage at a temperature of -20 degrees Celsius and can be stored in a regular refrigerator for up to 30 days. While Pfizer is common in medical facilities, Moderna takes the lead in community centers and non-medical locations.

“Many community centers or places that are not medical centers don’t have minus 80 freezers. Research facilities often have these ultra-freezers because they use them to store specimens,” Trivedi said. “The Moderna vaccine is more available and accessible for communities, clinics, other types of settings.”

Trivedi said the vaccine industry could learn about storing the Pfizer vaccine through the Dippin Dots industry. The industry manufactures freezers that store ice cream at -122 degrees Celsius to keep the treats sphere-shaped.

“They have these huge refrigerated freezer trucks essentially,” Trivedi said. “There was a lot of talk of how if Dippin Dots can get their products across the country, there is a lot the vaccine industry could learn about getting the vaccines across the country.”