Fake pharmaceutical drugs are fast becoming a major threat across the world. Mostly they are sold over the internet but they are also infiltrated into the neighbourhood pharmacies or local hospitals.

While the bogus medicines are responsible for half a million deaths a year, the death merchants themselves rake in billions of dollars, it has been estimated.

Bogus pharmaceuticals come in all combinations - some with no active ingredient, some with too little active ingredient, others with too much, some with toxic constituents. One seized consignment of phoney Ponstan, a non-steroidal anti-inflammatory, had no active ingredients at all; but it did contain boric acid, a pesticide that can cause renal failure. (The pills' colour came from leaded road paint.) Fake antibiotics have been intercepted that are made of talcum powder, as well as birth-control pills made of rice flour. Other ingredients have ranged from floor polish to rat poison.

The developing world records the majority of such deaths. In China, between 200,000 and 300,000 people are estimated to die each year because of counterfeit or substandard medicines. The WHO estimates that 200,000 of the one million malaria deaths a year would be prevented if all the drugs were genuine.

Fake vaccines killed 2,500 during a meningitis epidemic in Niger in 1995. Eighty-nine children died in Haiti the same year after swallowing paracetamol cough syrup that had been made with cheap, toxic diethylene glycol. In Nigeria in 2003, three children died during open-heart surgery because the adrenaline and suxamethonium, a muscle relaxant, used were fake. Prof Dora Akunyili, the director of the country's food and drug agency, said, 'The evil of fake drugs is worse than the combined scourge of malaria, HIV/Aids, armed robbery and illicit drugs.'