Malaria, one of the world's most common and serious tropical diseases, causes at least one million deaths every year -- the majority of which occur in the most resource-poor countries.  More than half of the world's population is at risk of acquiring malaria, and the proportion increases each year because of deteriorating health systems, growing drug and insecticide resistance, climate change, natural disasters and armed conflict.

State of the Pandemic
At least 300 million acute cases of malaria occur worldwide each year, resulting in more than one million deaths annually -- more than 80% of which are estimated to occur in sub-Saharan Africa, mostly among children under five years old.  Recent estimates of the global burden of malaria are even higher, with one study estimating that 515 million cases of clinical malaria occurred in 2002.  Overall, malaria accounts for 10% of Africa's disease burden, and it is estimated that malaria costs the continent more than $12 billion annually. Although Africa is hardest hit, it is estimated that more than one-third of clinical malaria cases occur in Asia and 3% occur in the Americas. The estimated cost to effectively control malaria in the 82 countries with the highest burden is about $3.2 billion annually.

Young children and pregnant women are at the highest risk of malaria infection and mortality. Many children experience initial malaria infection during their first two years of life, when they have not yet developed sufficient immunity, making these early years particularly dangerous.  Malaria accounted for one in 10 deaths among children in developing countries in 2002. Pregnancy causes women to have reduced immunity to malaria, making them more susceptible to malaria infection and increasing their risk of illness, severe anemia and death.  Approximately 60% of all cases of malaria occur among the poorest 20% of the world's population.

Although there are several different treatments for malaria, widespread resistance to conventional antimalarial drugs has contributed to increasing morbidity and mortality. Multidrug-resistant malaria is now prevalent in many parts of the world, with the highest rate of drug resistance in Southeast Asia. The inappropriate use of antimalarial drugs has contributed to the current situation. Over the past decade, a new group of antimalarials -- the artemisinin compounds -- have begun being used in combination with other drugs and on an increasingly large scale. These therapies produce a rapid response and are active against multidrug-resistant malaria. As a response to increasing levels of antimalarial resistance, WHO now recommends that all countries experiencing malaria cases that are resistant to conventional therapies use combination therapies.