Next time you hesitate to go along to give blood, just spare a thought for Mitchell Theisz

But unlike most children his age, there is a secret to Mitchell's success. Once a month, he travels to the Royal Children's Hospital to receive a rare and expensive substance his mother, Dianne, calls liquid gold.

This precious substance is immunoglobulin a rich soup of antibodies taken from hundreds of other people's blood donations. Without it, Mitchell's body cannot fight foreign germs.

When he receives an infusion, he usually becomes quite hyperactive, Mrs Theisz says. It really gives him a boost because in the days leading up to his dose, he starts losing energy. Sometimes you can tell that he's running low, you can see it in the way he holds himself."

Shortly after Mitchell was born, he was diagnosed with a primary immunodeficiency called X-linked agammaglobulinaemia or XLA. The condition means his body does not produce enough antibodies to neutralise infections. If he doesn't receive monthly intravenous doses of immunoglobulin (also known as IVIg), a minor infection can become life-threatening.

The IVIg has kept him pretty well, but every now and again he can get quite sick," Mrs Theisz says. "Earlier this year, he came home with a temperature and so I had to take him to hospital where he stayed for a few days. For Mitchell, a fever could mean pneumonia, so we have to be very careful about staying on top of these sorts of things.

I've also told his school that if any of the kids have anything, chicken pox, measles, anything, they must call me immediately. Any of those things could be a problem because Mitchell's condition has meant he couldn't have immunisations like other kids.

Mitchell is one of thousands of Australians who rely on IVIg to stay healthy and, arguably, alive. But unfortunately, the list of people who want access to this special product has started to outstrip supply.

A recent Government review found that despite the best efforts of the Australian Red Cross Blood Service to increase blood donations in line with demand, there was not enough plasma being donated to make enough IVIg for everyone who could benefit from it.

A set of clinical guidelines concluded the product was effective for 12 conditions, including immunodeficiency diseases like Mitchell's. It also found there was emerging evidence of its therapeutic benefit for another 22 conditions, but it warned doctors to be frugal.

When IVIg is used, the lowest dose for the shortest duration required to achieve the desired outcome should be chosen," say the guidelines, which came into effect last year.

The national operations manager for the Australian Red Cross Blood Service, Philippa Hetzel, says although the guidelines effectively prioritise patients and their doses, they also give a larger number of people access to the product.

We are now predicting a 100 per cent increase in demand over the next 10 years that is a 10 per cent increase every year for blood because of the increasing number of people coming onto the IVIg program," she says.

Not only is there an increasing list of conditions for which IVIg

can be useful, but people are also living longer and developing conditions for which it is needed."

While the Government started importing IVIg in 2004 to boost stocks, Dr Hetzel says the service is constantly aiming to increase Australian donations to meet the predicted demand.

The service needs more than 100,000 new donors for Australia to become self-sufficient and one of its key challenges is educating Australians about how much blood is required, who needs it, and on what basis.

Most people tend to associate blood shortages with crises like the Victorian bushfires when, in fact, a lot of the demand comes from people who are fighting chronic diseases for long periods of time," Dr Hetzel says.

A lot of people don't realise that the shelf-life of our products is short too, so we need donors to be coming in regularly all year round, not just in a crisis."

Dr Hetzel says the service is striving to recruit new donors with more comfortable chairs, televisions and possibly internet access soon. It has also changed its collection hours to make it easier for people to donate after work and on weekends.

Mrs Theisz has been assured that Mitchell's supply of IVIg is secure, but she is acutely aware of the need for more donors.

When Mitchell was about three months old, I remember the hospital telling us they needed to halve his dose because of a shortage," she says. "It's the only time it's happened to us, but it made me realise that if they keep supplying it to more and more people with different conditions, where will they draw the line?

I think if people realised how much of a life-saver their blood is for people like Mitchell, they would not hesitate to go in every three months. It's not a big ask to save other people's lives."