Chapter 1 of 16
Infectious diseases are the biggest killer of the young
|An infectious disease
crisis of global proportions is today threatening hard-won gains in health and life
expectancy. Infectious diseases are now the world's biggest killer of children and young
adults. They account for more than 13 million deaths a year - one in two deaths in
Over the next hour alone, 1 500 people will die from an infectious disease - over half of them children under five. Of the rest, most will be working-age adults - many of them breadwinners and parents. Both are vital age groups that countries can ill afford to lose.
Most deaths from infectious diseases occur in developing countries - the countries with the least money to spend on health care. In developing countries, about one third of the population - 1.3 billion people - live on incomes of less than $1 a day. Almost one in three children are malnourished. One in five are not fully immunized by their first birthday. And over one third of the world's population lack access to essential drugs. Against this backdrop of poverty and neglect it is little wonder that deadly infectious diseases have been allowed to gain ground. Today some of the poorest countries are paying a heavy price for the world's complacency and neglect.
All this has been made worse by the huge increase in mass population movements over the past decade. In 1996, as many as 50 million people - 1% of the world's population - had been uprooted from their homes. Not only are refugees and displaced people especially vulnerable to infectious disease; their movement can help spread infectious diseases into new areas.
Meanwhile, the growth of densely populated cities with unsafe water, poor sanitation and widespread poverty has created the perfect breeding ground for outbreaks of disease. In deprived inner-city areas children are less likely to be immunized against killer diseases and parents are less likely to be able to pay for health care when they get sick. Under these circumstances, diseases that were once under control can rapidly gain a foothold and re-establish themselves.
In addition, many diseases once thought unrelated to infectious diseases - especially cancers - are now known to be the result of chronic infections. Cervical cancer, for example - one of the most common cancers among women in the developing world - is now known to be associated with human papillomavirus infection. Meanwhile, chronic infectious hepatitis B and hepatitis C can both cause liver cancer and it is estimated that over 6% of the world's population is at risk. And bladder cancer can result from chronic infection with schistosomiasis.
But infectious diseases are not just a developing country problem. Unless checked, the crisis threatens the industrialized countries as well. Old scourges such as tuberculosis and diphtheria have occurred in explosive epidemics in Europe and other industrialized countries. And a 1996 outbreak of polio in Albania, Greece and the Federal Republic of Yugoslavia showed how easily a disease can be reintroduced to countries once free of the disease if immunization coverage is allowed to drop. A rapid increase in air travel has meant that diseases can now be transported from one continent to another in a matter of hours. Even today, no country is safe from the threat of infectious diseases.
Because the scale and complexity of the infectious disease crisis is so great, and the causes linked so closely to poverty, there is a tendency for some to be fatalistic about the situation. But the situation is far from hopeless. Efforts to prevent and control those diseases are among the most practical and achievable ways of alleviating poverty and furthering social and economic development.
This report argues that we have a window of opportunity to make dramatic progress against ancient diseases, and to establish an early warning system to protect us from new and unexpected diseases. If we fail, increased drug resistance and the emergence of new bacteria and viruses threaten to make the control of infectious diseases both scientifically and economically unlikely in the future.
|© World Health Organization 1999
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