A whistleblower who revealed the spread of HIV and hepatitis C through contaminated blood in central China during the 1990s and was subsequently targeted by authorities has died, aged 59, while hiking in the US.

Dr Shuping Wang may have saved tens of thousands of lives when Chinese authorities began testing for the diseases at blood banks as a result of her campaigning. However, even after her recommendations were taken up, Wang faced intimidation as officials tried to cover up the public health crises.

Wang was hiking in a canyon in Salt Lake City, Utah, when she had what appeared to be a heart attack, the Washington Post quoted her husband, Gary Christensen, as saying.

Wang had lived in the US since leaving China in 2001. She became a naturalised citizen and never returned to her birth country because she said she did not feel safe.

In 1992, Wang raised the alarm over how blood plasma donors were being contaminated with the blood of donors infected with hepatitis C when the blood of the latter was injected into the plasma donors’ bodies.

“My own investigation found the hepatitis C antibody positive rate to be as high as 84.3%. Being a doctor, I was very anxious,” she wrote. “I knew that hepatitis C and HIV had the same routes of infection … I didn’t want to sit in the office of the Health Bureau waiting for the arrival of an AIDS epidemic. I wanted to directly monitor it and prevent it.”

The Ministry of Health in Beijing began requiring hepatitis C screening for blood plasma donors in 1993 after Wang spoke out, but she was attacked, lost her job and had her clinic vandalised.

Then, in 1995, she uncovered another scandal in which HIV-positive donors were giving blood in a number of different areas. Wang told her superiors to test for HIV in all blood collection stations in Henan province, but was told it would be too costly.

She bought testing kits herself and found the HIV-positive rate among 400 donors to be 13%. As a result of her investigation, collection sites across China were shut down and later reopened with HIV testing.

In 2001, the government admitted that more than half a million often poor people were thought to have been infected with HIV after selling their blood to collection centres in central China.

A play, the King of Hell’s Palace, currently showing in London, was inspired by Wang’s story, and Chinese security officials have been accused of targeting her family and friends to try to force the Hampstead Theatre to abandon the production.

Wang, who reportedly attended the premiere, said relatives and former colleagues had been visited and told to instruct her to scrap the show, while officials also attempted to obtain contact details for her daughter.

“The only thing harder than standing up to the government and their security police is not giving in to pressure from friends and relatives who are threatened with their livelihoods, all because you are speaking out,” she said. “But even after all this time, I will still not be silenced, even though I am deeply sad that this intimidation is happening yet again.”

She added: “I am particularly concerned for my daughter, who is very scared about being approached ... Their reason is that this play will embarrass and damage the Chinese government and the reputations of specific officials.”