Convalescent Plasma Therapy

Convalescent plasma is a way to artificially induced passive immunity by transferring blood plasma from patients who have had a disease to previously untreated patients. This can give the recipient immunity against the disease due to the antibodies present in the blood plasma. Although recent reports have questioned its effectiveness, convalescent plasma therapy is one of the proposed therapies for COVID-19.

What is plasma?

Plasma is the liquid part of your blood. It is light yellow and comprises 91 to 92 percent water. It makes up about 55 percent of your blood, and the other 45 percent are red blood cells, white blood cells, and platelets. When your body is exposed to a foreign pathogen, your body's response is to produce antibodies, which are proteins that can bind to the virus and help deactivate it, clear it from circulation, and prevent it from invading the cells of the body.

What is convalescent plasma therapy and how does it work?

When people get sick with Covid-19, their immune system makes antibodies to fight the disease. Antibody proteins float in the blood plasma, which is the liquid layer of blood that keeps blood cells suspended. Doctors can collect the plasma, test for safety, and then purify it to isolate those antibodies. That "plasma-derived therapy" or "convalescent plasma" can be injected into another sick Covid-19 patient, and the antibodies it contains can help fight the virus in the early stages of infection until the patient's immune system patient generates his antibodies, in sufficient quantities to defeat Covid-19.

Who can donate plasma?

Patients who have been through the coronavirus cycle and recovered from COVID-19 can donate plasma. After 14 days of infection treatment, 500 mL of plasma will be donated. According to the information available on the Delhi Plasma Bank website, there are seven categories of people who cannot donate plasma. This includes diabetics who take insulin, pregnant women, people weighing less than 50 kg, cancer survivors, and others.

Convalescent plasma and disease outbreaks

During times of epidemics or pandemics, when many people are sick and many are at risk, convalescent plasma therapy receives a lot of attention. This has been the case with the Ebola, Junin virus, and COVID-19 epidemics, to name a few. Convalescent plasma is considered to have been used effectively in the treatment of SARS, MERS, and the 2009 H1N1 pandemic. One of the most successful documented examples of where the convalescent plasma was used was during the Junin virus epidemics. The mortality rate of patients treated with convalescent plasma was substantially decreased, down from 43% to 3%. The selection of plasma donors can be difficult because subjects and donors must match. Similarly, during disease outbreaks, results may be more effective if locally donated plasma is used in local subjects. This is due to variation in pathogen strains between locations.

What to expect

Your doctor may consider convalescent plasma therapy if you are in the hospital with COVID-19. Ask your doctor if you have any concerns about convalescent plasma treatment. Your doctor will request convalescent plasma from nearby hospital blood, provided that is consistent with your blood type.

Before procedure

Before convalescent plasma therapy, your healthcare team prepares you for the procedure. A member of your healthcare team inserts a sterile single-use needle connected to a tube (intravenous or IV) into a vein in one of your arms.

During procedure

When the plasma arrives, the sterile plasma bag is attached to the tube and the plasma drips from the bag into the tube. It takes between one and two hours to complete the procedure.

After procedure

Before convalescent plasma therapy, your healthcare team prepares you for the procedure. A member of your healthcare team inserts a sterile single-use needle connected to a tube (intravenous or IV) into a vein in one of your arms.

Risks

Blood has been used to cure a variety of ailments. It is usually very safe. The risk of contracting COVID-19 from convalescent plasma has not yet been evaluated. But the researchers believe the risk is low because the donors have fully recovered from the infection. There are some complications associated with convalescent plasma treatment, including: