China has been declared malaria-free by the World Health Organization in what the UN agency described as a “notable feat” given the high prevalence of the disease in the country 80 years ago.

China’s “success was hard-earned and came only after decades of targeted and sustained action”, said Tedros Adhanom Ghebreyesus, director-general of the WHO, on Wednesday.

After recording more than 30m cases of malaria annually in the 1940s, China implemented an eradication programme that by the late-1990s had brought annual cases to about 117,000 and reduced deaths by 95 per cent. In 2010, the government set a target of eradicating malaria by 2020.

China is one of several countries to be declared malaria-free in recent years, including El Salvador, Algeria and Argentina. In contrast, in sub-Saharan Africa, where more than 90 per cent of the world’s 400,000 annual malaria deaths are recorded, infections have remained stubbornly high after failed early elimination efforts saw governments switch to control strategies.

China applied to the WHO for malaria-free certification in 2020, after reporting no indigenous cases of malaria for four years.

Foreign ministry spokesperson Wang Wenbin hailed the landmark, which comes on the eve of the Communist Party’s 100th centenary celebrations, as “another great achievement for China”.

China’s success was much helped by the government’s early distribution of insecticide-treated malaria nets, which it started using in the 1980s ahead of many other countries.

Chinese scientists have also developed groundbreaking antimalarial drugs. In 1967, despite the violence and university closures caused by Chairman Mao Zedong’s Cultural Revolution, which began a year earlier, the government launched the “523 Project” bringing together researchers to find new malaria treatments.

The head of the 523 project, Tu Youyou, later became mainland China’s first Nobel laureate in the sciences after she isolated artemisinin, a compound whose derivatives are now used in front-line malaria drugs. Tu’s discovery has been hailed by the Lasker Foundation, which awards its own prizes for medical research, as “arguably the most important pharmaceutical intervention in the last half-century”.

Sir Brian Greenwood, professor of clinical tropical medicine at the London School of Hygiene and Tropical Medicine who advises the WHO on malaria suppression, said China’s achievement was “particularly impressive” given its proximity to at-risk countries and its close trading ties with sub-Saharan Africa, where the disease is still prevalent.

The elimination of malaria in China offers a “resounding message to the heartlands of the disease” in India and Africa that eradication is “eminently possible”, he said.

“The critical thing is that [China] sustains the funding because there will be a temptation . . . to lose focus,” Greenwood continued. “They need to keep up the high level of surveillance, public education and medical expertise. That will require continued investment.”

Since the coronavirus pandemic began, Chinese state media and foreign ministry spokespeople have sought to emphasise the government’s success in controlling Covid-19 at home, as the virus has spread faster and further in other parts of the world.

Prof Therese Hesketh, director of the Centre for Global Health at Zhejiang University, said the government fanfare around the malaria announcement was another example of Beijing’s growing emphasis on “health diplomacy”.

“[Malaria] was never very high in the ranking of disease mortality in China because it’s very regional,” said Hesketh. “But [eradicating the disease] fits neatly into China’s powerful agenda and narrative around controlling infectious disease.”