A campaign is being launched today to get more people to donate their blood plasma for medicines.
Plasma donation only restarted in April after a gap of more than 20 years but NHS figures suggest only 23% of the public know about it, which adds to the shortfall in people coming forward.
There are 714 active plasma donors at the Chelmsford donor centre, which is in Victoria House on Duke Street, compared to the 857 active plasma donors needed.
Plasma donation is expanding and by the end of September, NHS Blood and Transplant will need about 1,000 more active plasma donors at Chelmsford.
In total, NHS Blood and Transport said it needs 14,500 people to start donating plasma within the next three months to get NHS donation back on track.