IN ABOUT eight years, instead of popping pills over 10 days to clear up the flu, patients can have a blood cleansing procedure to get the flu virus out of their bodies.

National University of Singapore (NUS) scientist Tong Yen Wah, 34, has come up with a 'sieve' he is hoping will 'trap' viruses which cause diseases such as the flu, the Severe Acute Respiratory Syndrome and the Acquired Immunodeficiency Syndrome.

His sieve will contain tiny moulds specially shaped to recognise the shapes of viruses and catch them. By locking arms with these viruses, the moulds make the viruses powerless to infect the human body.

Dr Tong's moulds act like synthetic antibodies to kill the viruses, something the body's immune system also does.

In a procedure similar to kidney dialysis, a patient's blood can then be extracted, pumped through the sieve, have the inactive virus removed, and then have the blood returned to the body.

Dr Tong has just received US$100,000 (S$150,000) from the Bill and Melinda Gates Foundation to attempt this. And if he can show it works in the next year, he will get another US$1 million to continue work on his 'virus catcher' for two more years.

The Foundation is set up by software giant Microsoft's founder, Bill Gates and his wife. One of the projects the Foundation supports is innovation in global health, especially if it goes towards reducing cost, making heathcare more accessible to poorer countries.

A specialist in infectious diseases at Tan Tock Seng Hospital, Dr Lim Poh Lian, 43, said that a project such as Dr Tong's was a 'potentially feasible project' because therapies involving natural antibodies from the body already exist.

'So it is well worth considering making synthetic antibodies,' she said.

Dr Tong said his mould could also bring down the cost of producing drugs. Drug companies are increasingly looking at using proteins - which are large molecules - to make drugs. Traditionally, drugs, such as aspirin, are made up of small molecules. Insulin and breast cancer drug Herceptin are made from large molecules.

But the process of purifying these proteins consists of many steps and chemicals. Dr Tong said his mould can do this in fewer steps, using just water and an acid solution.