With COVID-19 restrictions winding down in New York State and vaccination rates climbing, our local population seems to be headed back to normalcy.
However, with places like England, Japan, and India experiencing recent spikes in COVID-19 cases, it's clear that the world is not free of the pandemic just yet.
In their recent talk, "SARS CoV-2 Virus, the COVID-19 Pandemic, and Vaccination," Mount Saint Mary College professors Evan Merkhofer and James Moran (Biology) and Christina Alvey (Mathematics and Information Technology) discussed the biology of coronaviruses, their infectiousness in humans, and the mathematics of recovery.
The SARS CoV-2 virus responsible for the COVID-19 pandemic is among the newest members of a family of coronaviruses that cause upper-respiratory tract infections in animals and humans. The pandemic was declared on March 11, 2020 by the World Health Organization and, at the time of this writing, it is still ongoing.
According to Merkhofer, most coronaviruses cause mild or moderate illness in humans: for example, the common cold is caused by a kind of coronavirus. However, COVID-19 has had a huge global impact, with more than 110 million people around the world infected and more than 2.5 million deaths.
Like other viruses, COVID-19 replicates itself by inserting its RNA into a host cell, which makes copies of the virus. These copies then go on to infect other host cells.
"This is essentially the life cycle of the [SARS CoV-2] virus," said Merkhofer. "That is all it does – infect cells and make more viruses. And quite frankly, it's very good at it."
Few viruses cause pandemics, so what makes the SARS CoV-2 virus different? That's down to several factors, noted the three professors:
- Human immune systems have not dealt with COVID-19 before.
- ACE2 is an enzyme attached to the membrane of cells located in places like the intestines, kidneys, and heart. ACE2 acts as a receptor for the virus that causes COVID-19. Thus, the virus can infect cells other than those in the respiratory tract.
- SARS CoV-2 has a high ability to stick to cells and therefore spread in a population.
- It can be spread while the carrier is asymptomatic – up to 14 days.
- New variants have emerged.
Many hopes for a return to normalcy hinge on the mass distribution and efficiency the COVID-19 vaccines that have received emergency use authorization from the Food and Drug Administration. Moran noted that the vaccines imitate infections in their ability to create immunological memory cells in a person's body.
"The idea here with vaccination is to mimic what happens during a natural infection, to be able to build that immunological memory without all of the nasty consequences," he explained.
Both the Pfizer and Moderna shots are mRNA vaccines, said Moran. This means they carry genetic information for part of the SARS CoV-2, specifically the virus spike protein that allows it to stick to human cells.
"There is no full virus here, it's just a code for part of the viral spike protein," said Moran. "So you can't get COVID from these types of vaccines."
The Johnson & Johnson version is a non-replicating human adenovirus vaccine. It uses a virus that can't replicate or cause disease to deliver genetic material into cells.
"It's really just a delivery mechanism to get that genetic code for that coronavirus spike inside the cells," Moran said. "So once again, because the adenovirus can't replicate or cause disease, there is no risk associated with having any type of infection going on with this vaccine either."
The talk was part of the Mount's ongoing Investigating Research on Campus (iROC) series, which is free and open to the public. The series provides a forum for Mount faculty, staff, and students to showcase their research endeavors with the college and local communities. Presentations include research proposals, initial data collection, and completed research projects.
Planning for the Fall 2021 series of iROC talks is already underway.