Stephen McGrath, New Lambton, was one of the first in the Hunter to start donating convalescent plasma - a blood product that could prove to help people recover from COVID-19.

Convalescent plasma contains antibodies that remain in a person's system after they have beaten the virus.

Plasma donated from recovered patients is being used in clinical trials in the UK, USA, China and Canada in the hope it can boost the immunity of those battling the illness.

Red Cross said earlier this month - and it has been widely reported - that it was starting to collect plasma from people who have recovered for clinical trials in Australia.

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Mr McGrath said he was three weeks into a 12-week donation plan - he gives plasma once a week and donated at the Broadmeadow clinic on Wednesday morning.

A regular Red Cross donor, he told the Newcastle Herald the experience was much like giving blood.

"It's the same as giving blood normally, except they take out the plasma and give your red blood cells back, so you can donate more often," the 36-year-old engineer said.

"If you're not scared of needles, it's fine."

Mr McGrath believes he picked up COVID-19 during a business trip to the US city of Denver in March.

He said his symptoms did not appear bad but he got tested when he returned home as a precaution.

What he thought were sore eyes, sinus issues and a runny nose from 40 hours of travel across the globe turned out to be coronavirus.

"I did have slight chills but it wasn't enough to have a temperature," Mr McGrath said.

"I had one day where I did get a really tight chest. Then it was just like having really bad asthma.

"A few days later I felt 100 per cent."

He said he contacted Red Cross after his recovery and quarantine to see if there was anything he could do to help, which resulted in the plasma donations.

Aside from having recovered from COVID-19, anyone who wants to donate convalescent plasma also has to meet Red Cross's eligibility criteria.

It can only be donated by people who have had a confirmed laboratory diagnosis of COVID-19 and who have fully recovered and been symptom-free for at least 28 days.

"Donating plasma is a simple, powerful act that could help a patient struggling to fight the disease," Australian Red Cross Lifeblood chief executive Shelly Park said.

"It is a real opportunity for people who have battled COVID-19 to become part of a potential solution."