The Australian Red Cross Blood Service has issued an urgent appeal for people with the universal O-Negative blood type to donate blood, with the nation having just two days’ supply left.

Cold and flu symptoms have wiped out up to 1000 donors a day and are placing a strain on existing donors, service spokesman Shaun Inguanzo said.

Mr Inguanzo appealed for new donors to come forward and roll up their sleeves.

"O-Negative is the universal type given to patients in emergency situations, when their blood type is unknown," he said.

"Australian patients need around 500 O-negative donations a day to survive these situations.

"With one in three of us needing donated blood in our lifetime the life you save could be that of friend or family member."

Mr Inguanzo said maintaining O-Negative supplies was often a challenge in winter.

"The number of people suffering cold and flu symptoms increases, limiting the number of regular donors who are able to give," he said.

"Around the country, we are seeing as many as 1000 people cancel their appointments every day, almost half of them due to illness.

"We need others – in this case people with O-negative blood – to take the place of those who have cold or flu symptoms."

Anyone affected by cold and flu symptoms can donate blood seven days after they recover, Mr Inguanzo said.