A second case of a possible transmission of vCJD via a blood transfusion has been revealed by the Department of Health.
The government is bringing in new restrictions on blood donation
The patient died from causes unrelated to the disease, but a post mortem found the vCJD agent in their spleen.
The patient received the transfusion in 1999 from a donor who later developed vCJD, according to information from the National CJD Surveillance Unit.
The CJD Support Network said the news confirmed its worst fears.
In December last year, the first reported case of a patient who died of vCJD after receiving blood from an infected donor was revealed.
The case was thought to be the first person-to-person transmission of vCJD in the world.
The patient had received blood during an operation in 1997 developed variant CJD and died six years later.
At the time, Health Secretary John Reid said in a statement to the House of Commons, "This is possibly not a proven causal connection - it's also possible that both individuals acquired CJD separately.
"This is a single incident, so it is impossible to be sure which was the route of the infection. However, the possibility of this being transfusion-related cannot be discounted."
In response to that case, the government banned anyone who had received a blood transfusion since January 1980 from donating blood in the
It has now said it will extend the ban to cover a larger group of transfusion recipients from August 2.
Potential donors who are unsure if they have had a transfusion and those who regularly donate blood components will be covered by the new restrictions.
Announcing the extended measures, Mr Reid said: "We are continuing to follow a highly precautionary
"Although people may have concerns about the implications of this announcement, I would emphasise again that the exclusion criteria are being tightened because of a small but unquantifiable risk.
"People should continue to have a blood transfusion when it is really necessary.
He added: "Any slight risk associated with receiving blood must be balanced against the significant risk of not receiving that blood when it is most needed."
Shadow Health Secretary, Andrew Lansley, supported the government's "highly precautionary" approach.
But he said: "It is important to assess to what extent the process of leucodepletion - the removal of white blood cells in blood used for transfusion - has contributed to reducing this risk.
"The second possible case of transmission in the department's announcement concerned a transfusion in 1999 but it doesn't make clear whether it was prior
to the implementation of leucodepletion in October 1999."
Paul Burstow, Liberal Democrat health spokesman added: "The government must ensure that people prevented from donating are reassured about the risks involved.
"Ministers must be ready to take urgent steps to encourage blood donation if the blood supply is affected by today's announcement.
Latest figures show 142 people have died so far from probable or confirmed vCJD.
Since 1997 all cases of vCJD that are reported to the National CJD Surveillance Unit and diagnosed as having 'probable' vCJD, are passed on to the National Blood Service which searches its blood donor records.
If the patient has given blood, subsequently any stocks of that blood are immediately destroyed.
Blood products, such as clotting factors, have been prepared from plasma imported from the USA since 1998.
And white blood cells (which may carry the greatest risk of transmitting vCJD) have been removed from all blood used for transfusion since 1999.