Asia

Malaria has been present in Asia since the first humans walked out of Africa into Asia, bringing their parasites with them. Sumerian and Egyptian texts of four thousand years ago recorded malaria’s presence among the people. Antigens to plasmodium falciparum have been found in 5,000-year-old mummies from Egypt and Nubia. In China, malaria was the “mother of fevers.” In India, 3,500 years ago, it was the “king of diseases,” personified by the fever demon Takman. Vedic sages advocated nothing less than obeisance. “To the cold Takman,” they wrote, “to the shaking one, and to the deliriously hot, the glowing, do I render homage. To him that returns on the morrow, to him that returns for two successive days, to the Takman that returns on the third day, shall homage be.”

European colonization introduced new patterns of development that altered the balance between human, mosquito, and parasite. In India, for example, the British built thousands of miles of irrigation canals without digging drainage ditches or clearing vegetation, creating ideal mosquito hatcheries which led to explosive malaria epidemics. In 1908, a catastrophic malaria epidemic tore through the Punjab and the United Provinces, the most heavily irrigated regions. By the time it ended, over five million Indians died. In the wake of the Punjab epidemic, the colonial government voted against addressing the poor drainage that contributed to it. (The nominal malaria policy was to administer quinine, even though the entire world supply of quinine times fifty wouldn’t’ have been sufficient for India’s malaria caseload.) Malaria epidemics roiled British India in 1917, 1933, and 1942. The League of Nations called the British malaria policy in India “sanitary inaction.”

Many Asian countries undertook DDT campaigns against malaria in the 1950s. By 1961, India suffered less than 100,000 cases of the disease. Freed from malaria’s grip, rice cultivation increase by tenfold in Indonesia and Sri Lanka. In the Philippines, previously uninhabitable regions were settled. In Cambodia, land values doubled. Between 1946 and 1956, Sri Lankan malaria cases declined from 3 million to 7,300—and there were no deaths at all.

Malarial mosquitoes soon evolved resistance to DDT. In Sri Lanka, a 1966 outbreak was traced to a contractor’s camp, where infected workers had already departed for 58 other villages. Trouble was brewing; and then in 1968-69, malaria infections skyrocketed to over 500,000. The local vector, Anopheles culicifacies was no longer susceptible to DDT, and malaria cases quickly rebounded to over 400,000 in 1975. In 1974, a three-year malaria epidemic rippled across India, striking 25 million.

Drug-resistant strains also first emerged in Asia. Between 1961 and 1962, parasites resistant to the antimalarial pyrimethamine emerged in Cambodia (as well as the Netherlands and Brazil). Plasmodium falciparum resistant to chloroquine, distributed in WHO-sanctioned medicated table salts, emerged in Thailand (as well as Colombia, Brazil, and Venezuela).

During the US-Vietnam war, chloroquine-resistant malaria struck thousands of U.S. soldiers. More hospital beds were filled with malaria patients than with those wounded by the enemy. Chloroquine-resistant falciparum malaria hung over the Ho Chi Minh trail, posing a lethal threat to the Vietcong. After a month-long journey down the trail, only 120 of 1,2000 Vietcong soldiers were fit to fight. “They had a saying: ‘We fear no American imperialists, only malaria,’” remembers Vietnamese battlefield doctor Zhou Yiqing. The malarial toll on the Ho Chi Minh trail motivated Chairman Mao in China to launch a malaria drug program that ultimately led to the development of artemisinin-based treatments, which today are the WHO’s drugs of choice.

Drug-resistant strains of malaria have now spread across the globe. The border region between Cambodia and Thailand, with its influx of mobile populations (in particular, gem miners) and streams of counterfeit and substandard drugs, continues to be an epicentre for the emergence of drug-resistant strains of malaria, most recently rendering falciparum malaria resistant to artemisinin-based treatments. In 2003, artemisinin treatments failed in 20 percent of malaria cases in Trat, a southeastern province of Thailand. In January 2007, WHO advisers recommended that the agency begin to plan for the eventual emergence of artemisinin-resistant malaria—what they call multi-drug resistant malaria (MDR), which will pose a potent threat to malaria control activities worldwide.

In 2005, there were an estimated 18.56 million cases of malaria in southeast Asia, with 99,185 deaths, accounting for 30 percent of the global malaria burden.

For more:

WHO Southeast Asia Regional Office:
http://www.searo.who.int/EN/Section10/Section21/Section340_4018.htm

“Containment of malaria multi-drug resistance on the Cambodia-Thailand border,” WHO report of an informal consultation, Phnom Penh, 29-30 January 2007

www.who.int/malaria/docs/drugresistance/ReportThaiCam.pdf

Malaria risk in Asia
http://malariasite.com/malaria/asia.htm