Thousands of haemophiliacs have filed a lawsuit in the US against four companies for allegedly exposing them to the HIV virus by selling products made with contaminated blood.
The lawsuit alleges the companies continued distributing the blood-clotting products in Asia and Latin America in the 1980s, despite having stopped selling them in the US because of the known risk of passing on HIV and hepatitis C.
The four companies named are: Bayer Corporation, Baxter Healthcare Corporation, Armour Pharmaceutical Company and Alpha Therapeutic Corporation.
The lawsuit alleges that they purchased plasma from "the highest-risk populations, including prisoners, intravenous drug users and blood centres targeting promiscuous urban gays" and that they failed to exclude donors with a history of viral hepatitis
The lawsuit was filed less than two weeks after the New York Times accused Bayer of selling old stock of the medicine abroad, while marketing a newer, safer product in the United States.
When contacted by BBC News Online on Tuesday, the company declined to comment on the lawsuit.
The medicine, called Factor VIII or IX concentrate, can stop or prevent bleeding in people with haemophilia - a disorder of the blood-clotting system.
At that time, early in the Aids epidemic, the medicine was made using mingled plasma from 10,000 or more donors.
There was no screening test for the Aids virus, HIV, but the lawsuit alleges the companies failed to take precautions that could have made the product safer.
"This is a worldwide tragedy," said lawyer Robert Nelson, from US law firm Lieff Cabraser Heimannn and Bernstein.
"Thousands of haemophiliacs have unnecessarily died from Aids and many thousands more are infected with HIV or hepatitis C."
By 1992, the contaminated blood products had infected at least 5,000 haemophiliacs in Europe with HIV. More than 2,000 had developed Aids and 1,250 had died from the disease, the lawsuit said.
By the mid-1990s in Japan, haemophiliacs made up the majority of the country's 4,000 HIV patients, and virtually all of those infections have been linked to contaminated blood products from the US, the lawsuit said.
In Latin America, at least 700 HIV cases are linked to use of contaminated blood products by haemophiliacs, the lawsuit said.
There have been several Aids-related scandals around the world.
In China, hundreds of thousands of people were infected with HIV during a government-sanctioned, appallingly unsanitary blood-collection scheme in the 1980s and 1990s.
In 1999, a former French health minister was convicted for failing adequately to screen blood which led to the deaths from Aids of five people, and the contamination of two others during a key period in 1985. Two French ministers were acquitted of manslaughter.
Two years ago, Canada's Supreme Court found the Canadian Red Cross guilty of negligence for failing to screen blood donors effectively for HIV infection.
In most countries, Factor VIII and IX is now made artificially.