Contents Burden of infectious diseases 2 The biggest killer of the young Six diseases cause 90% of infectious disease deaths Infectious diseases are also among the biggest disablers Affordable to prevent 14 Avoidable at a low cost Controllable in any country The end of the line for some infectious diseases? Inadequate response 26 Investing in healthy development Many countries do not yet use WHO recommended policies Many factors contribute to the spread of infectious diseases Uncertain future 38 Diseases continue to catch the world off guard Near misses Medicines are losing their effectiveness The world is becoming a smaller place for microbes Staying prepared 54 Development of new drugs and vaccines The need for intensified research A call for healthy development 62 Notes: • Th roughout this report, the term "infectious disease" is used to refer to all communicable diseases, including parasitic and zoonotic diseases, and some forms of respiratory infections and diarrhoeal diseases . • $ refers to us·do llars. • The term "billion" is used to mean a thousand million. II The biggest killer of the young An infectious disease crisis of global proportions is All this has been made worse by the huge today threatening hard-won gains in health and life increase in mass population movements over the expectancy. Infectious diseases are now the past decade. In 1996, as many as 50 million world's biggest killer of children and young adults. people - 1% of the world's population - had been They account for more than 13 million deaths a uprooted from their homes. Not only are refugees year - one in two deaths in developing countries. and displaced people especially vulnerable to Over the next hour alone, 1 500 people will die infectious disease; their movement can help from an infectious disease - over half of them spread infectious diseases into new areas. children under five. Of the rest, most will be Meanwhile, the growth of densely populated working-age adults - many of cities with unsafe water, poor them breadwinners and sanitation and widespread parents. Both are vital age poverty has created the perfect groups that countries can ill breeding ground for outbreaks of afford to lose. disease. In deprived inner-city Most deaths from infectious areas children are less likely to be diseases occur in developing immunized against killer diseases countries - the countries with and parents are less likely to be the least money to spend on able to pay for health care when health care. In developing they get sick. Under these countries, about one third of the circumstances, diseases that population - 1.3 billion people - were once under control can live on incomes of less than $1 a day. Almost one rapidly gain a foothold and re-establish in three children are malnourished. One in five are themselves. not fully immunized by their first birthday. And over In addition, many diseases once thought one third of the world's population lack access to unrelated to infectious diseases - especially essential drugs. Against this backdrop of poverty cancers - are now known to be the result of and neglect it is little wonder that deadly infectious chronic infections. Cervical cancer, for example - diseases have been allowed to gain ground. Today one of the most common cancers among women some of the poorest countries are paying a heavy in the developing world - is now known to be price for the world's complacency and neglect. associated with human papillomavirus infection. Leading causes of death 53.9 million from all causes, worldwide, 1998 Other 6% Infectious diseases Respiratory and digestive 25% 9% Maternal 5% Injuries 11 % Cancers Cardiovascular diseases 13% 31 % Note: Cancers, cardiovascular and respiratory/digestive deaths can also be caused by infections and raise the percentage of deaths due to infectious diseases even more. Source: WHO, 1999 II Meanwhile, chronic infectious hepatitis B and Main causes of death hepatitis C can both cause liver cancer and it is estimated that over 6% of the world's population is in low-income countries at risk. And bladder cancer can result from chronic In South-East Asia and Africa Estimates for 1998 infection with schistosomiasis. But infectious diseases are not just a Maternal2% Nutritional 1% developing country problem. Unless checked, the Perinatal 6% 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 Noncommunicable conditions 35% meant that diseases can now be transported from Source: WHO, 1999 one continent to another in a matter of hours. Even today, no country is safe from the threat of infectious diseases. This is happening at a time when the arsenal resistance of microbes to antimicrobial drugs. of drugs available to treat infectious diseases is Because the scale and complexity of the being progressively depleted due to increasing 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. IR CONDITIONING has played a major role in the spread of Efforts to prevent and control those diseases are Legionnaire's disease - a form of among the most practical and achievable ways of bacterial pneumon1a. AThe infection is spread by water droplets alleviating poverty and furthering social and through air-conditioning systems. The . Legionella organism caused 29 deaths In economic development. a Philadelphia hotel in 1976 and 16deaths ' . a Los Angeles hospital the following year. This report argues that we have a window of In . I 0 f 172 11 is believed that1n 1995, a Iota uests in Western European hOtels had been opportunity to make dramatic progress against ;xposed 10 Legionella.ln ear~ 1999, 23 ancient diseases, and to establish an early participants in a flower show In the Netherlands died of the disease. warning system to protect us from new and II Main causes of death unexpected diseases. If we fail, increased drug resistance and the emergence of new bacteria among children and viruses threaten to make the control of Ages 0 to 4 years infectious diseases both scientifically and Estimates for 1998, worldwide economically unlikely in the future. Injuries 6% Noncommunicable conditions 8% The World Health Nutritional 3% Organization The World Health Organization (WHO) can Perinatal 20% help mobilize the partners and develop the policies that will prevent and control infectious diseases. There is still a window of opportunity to make dramatic progress against the diseases that have been with us for thousands of years Source: WHO, 1999 and to establish an early warning system to pro­ tect from new and unexpected diseases. WHO Main causes of was created in 1948 and today, with over 190 Member States, it is the lead agency in interna­ premature death tional health. WHO's goal is to foster the attain­ Ages 0 to 44 years ment by all peoples - especially the poor and Estimates for 1998, worldwide most vulnerable - of the highest possible Maternal 3% Nutritional 2% standards of health. The guiding principles of WHO are: • "We can't do it alone, so we work in partnership with others:' • 'We can't do it all at once so we set priorities. Noncommunicable Priority setting helps focus the world's atten­ conditions 18% tion, resources and actions on innovative and cost-effective public health action with specific goals and measurable results:' WHO is the health conscience of the world. • General WHO information can be accessed Source: WHO, 1999 at www.who.int Six diseases cause 90°/o of infectious disease deaths Most deaths from infectious diseases - almost young children and adult breadwinners, their impact 90% - are caused by only a handful of diseases. on families can be catastrophic. Children may lose And most of them have plagued mankind one or both parents to an infectious disease. The throughout history, often ravaging populations AIDS epidemic alone has left over eight million more effectively than wars. In an age of vaccines, children orphaned. To make matters worse, families antibiotics and dramatic scientific progress, these risk being driven into debt through lost earnings and diseases should have been brought under control. high health care costs- trapping them in a vicious Yet, in developing countries today they continue to circle of poverty and ill-health. kill at an alarming rate. And at times - as in recent outbreaks Pneumonia of influenza - they also kill at Acute respiratory infections (ARis) an alarming rate in the are responsible for many deaths. industrialized countries. Pneumonia, the deadliest ARI , kills No more than six deadly more children than any other infectious diseases infectious disease. Most of these pneumonia, tuberculosis, deaths (99%) occur in developing diarrhoeal diseases, malaria, countries. Yet in industrialized measles and more recently countries childhood deaths from HIV/AIDS - account for half pneumonia are rare. of all premature deaths, Pneumonia often affects killing mostly children and young adults. children with low birth weight or those whose Every three seconds a young child dies - in immune systems are weakened by malnutrition or most cases from an infectious disease. In some other diseases. Without treatment, pneumonia kills countries, one in five children die before their fifth quickly. birthday. Every day 3 000 people die from malaria The influenza virus is another cause of -three out of four of them children. Every year 1.5 pneumonia. There is very little information million people die from tuberculosis and another available on the number of influenza deaths in eight million are newly infected.