People who have recovered from the coronavirus may be eligible to donate plasma, which can then be administered to others who have not yet recovered.

Here is how it works:

What is plasma?

Plasma is the liquid component of blood. It is often infused in patients who undergo surgery and others who have lost blood.

In the case of people who have recovered from the coronavirus, the plasma also contains antibodies that their immune systems have developed to fight off the infection.

In theory, this antibody-laden plasma may be beneficial for other patients whose immune systems have not yet learned to make antibodies against the virus. In the United States, hundreds of patients have been treated this way so far, including two dozen in the Philadelphia area and New Jersey, though the benefit is unproven.

Who can donate?

The requirements vary by location. The American Red Cross requires that donors are 17 or older and weigh at least 110 pounds. As with other donations of plasma and blood products, the organization also requires that patients are in good health.

In order to donate plasma for use in treating patients with the coronavirus, donors must provide documentation that they tested positive for the virus. Donors also must be symptom-free for at least 14 days before donating.

» READ MORE: Plasma, a 19th-century treatment, is being used to battle coronavirus infections

What is it like to donate?

Plasma is collected from a donor in a process called apheresis, in which tubing is connected to the person’s arm. Blood flows through the tube to a whirring machine, which separates plasma from red blood cells and other solid components of blood.

The plasma, a golden fluid, is collected in a bag. The rest of the blood flows back into the donor. The process takes about 90 minutes.

Where you can do it

Do not simply show up at a hospital or blood bank expecting to donate plasma. People who have recovered from the coronavirus should first register with these sites to see if they are eligible:

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