A fatal complacency
Until relatively recently, the long struggle for control over infectious diseases seemed almost over. Smallpox was eradicated and half a dozen other diseases were targeted for eradication or elimination. Vaccines protected about eight out of 10 of the world's children against six killer diseases. Antimicrobial drugs were effectively suppressing countless infections. However, in the path of these successes, cautious optimism has been overtaken by a fatal complacency that is costing millions of lives a year. Infectious diseases are the world's leading cause of death, killing at least 17 million people - most of them young children - every year. Up to half the 5 720 million people on earth are at risk of many endemic diseases.
Far from being over, the struggle to control infectious diseases has become increasingly difficult. Diseases that seemed to be subdued, such as tuberculosis and malaria, are fighting back with renewed ferocity. Some, such as cholera and yellow fever, are striking in regions once thought safe from them. Other infections are now so resistant to drugs that they are virtually untreatable. In addition, deadly new diseases such as Ebola haemorrhagic fever, for which there is no cure or vaccine, are emerging in many parts of the world. At the same time, the sinister role of hepatitis viruses and other infectious agents in the development of many types of cancer is becoming increasingly evident.
The result amounts to a global crisis: no country is safe from infectious diseases. The socioeconomic development of many countries is being crippled by the burden of these diseases. Much of the progress achieved in recent decades towards improving human health is now at risk.