Plasma is the liquid part of blood.
It gets drawn out, and a machine separates it. The rest, like your red blood cells, gets returned to your body.
Plasma from survivors of COVID-19 is in high demand right now, because it has special antibodies that could help others suffering from the virus.
"We don't have any other specific treatments for COVID-19. This is nature's way of making a specific way of making a treatment for us. We are reusing people's immune systems to make a treatment, and we're hoping that it works," said Dr. Gustaaf de Ridder, director of transfusion services for Geisinger.
Treatments like this have been around a long time.
"This has been done for over 100 years. Back in the Spanish flu of 1918 through various diseases including mumps and most recently and relevantly with SARS in the early 2000s."
Dr. de Ridder said most people can easily donate plasma about once a week.
He said it is important to remember: plasma is not a surefire cure, but it is a treatment that doctors and scientists are still experimenting with and researching.
"We have some hope that we can help a person who is acutely ill with COVID 19 by giving them plasma from someone else who has gotten better. The idea is to blunt the impact of the disease on that new case, to keep them say out of the ICU or have fewer days on the ventilator," he said.
Dr. de Ridder said there is still a lot to learn. He is hopeful that it will help people in the future.
"I do believe we're going to learn a lot about convalescent plasma as therapy for viral pandemics from this," he said.
As for making a plasma donation, Dr. de Ridder said you should talk to your doctor first and make sure you meet the criteria.