World Health Organization declares China malaria-free

• A total of 40 countries and territories have been declared free of the disease.

What they're saying: "Today we congratulate the people of China on ridding the country of malaria," said Tedros Adhanom Ghebreyesus, WHO director-general.

• "Their success was hard-earned and came only after decades of targeted and sustained action. With this announcement, China joins the growing number of countries that are showing the world that a malaria-free future is a viable goal," he added.

History: China has been working to locate and stop the spread of the disease for decades. In the 1940s, the country reported approximately 30 million cases annually, according to the WHO.

• The Chinese government launched the "523 Project" in 1967 to find new malaria treatments. Through this process, Chinese scientists found artemisinin, the key component of the most effective antimalarial drug to date.
• By 1990, Chinese malaria cases decreased to 117,000, and deaths were reduced by 95%.
• China applied for a WHO certification of malaria elimination in 2020, after four consecutive years of reporting zero cases.

Between the lines: WHO warned that malaria could still return, noting that China's Yunnan province borders several malaria-endemic countries: Laos, Myanmar and Vietnam.