Good news on the malaria front
Nine of the 10 principal malaria-endemic countries in the Western Pacific Region are experiencing downward trends in the disease, but in some high-burden countries, notably Papua New Guinea, the rate of decline remains slow, WHO's World Malaria Report 2011 reveals.
Some 262 000 confirmed malaria cases were reported from the Western Pacific Region in 2010, with transmission patterns varying considerably. Transmission was intense through most of Papua New Guinea, Solomon Islands and Vanuatu, but localized in the countries and areas of the Greater Mekong subregion, including Cambodia, China's Yunnan province, Lao PDR and Viet Nam, where transmission was greatest in remote forested areas and where the disease disproportionately affects ethnic minorities and migrants.
In China, Philippines, Republic of Korea, and Viet Nam, the reported trends in confirmed cases were predominantly downwards, with the number of cases more than halved between 2000 and 2010.
However, drug resistance remains a major concern. Plasmodium falciparum resistance to artemisinins, which was confirmed on the Cambodia-Thailand border in 2009, is now suspected in parts of Myanmar and Viet Nam. However, artemisinin-based combination therapy remains highly effective in almost all settings, so long as the partner drug in the combination is locally effective.
WHO has recommended that all countries ban the marketing of oral artemisinin-based monotherapies, which have been one of the major factors fostering the emergence and spread of drug resistance. Despite a World Health Assembly resolution addressing this issue, 25 countries still permit the marketing of monotherapies and 28 pharmaceutical companies continue to produce these products (down from 39 in 2010).
The World Malaria Report 2011 says that 45 countries around the world have identified resistance to at least one of the four classes of insecticides used for malaria vector control; 27 of these are in sub-Saharan Africa.
The good news globally is that malaria mortality rates have fallen by more than 25% since 2000, with the largest percentage reductions seen in the European (down 99%), American (55%) and Western Pacific (42%) and African Regions (33%).
Out of 99 countries with ongoing malaria transmission, 43 recorded decreases of more than 50% in the number of malaria cases between 2000 and 2010. Another eight countries recorded decreases of more than 25%.
The 10 principal malaria-endemic countries in the Western Pacific Region are: Cambodia, China, Lao People's Democratic Republic, Malaysia, Papua New Guinea, Philippines, Republic of Korea, Solomon Islands, Vanuatu and Viet Nam.