The epidemiology of infection in childhood

Abstract

Worldwide infections as a disease group are responsible for most loss of life and good health among children. It was estimated that in 1990, infectious diseases were responsible for 8.3 million of a total of 12.5 million deaths among a global child population (under 5 years-of-age) of 6301 million, and projections to the year 2020 suggest that this burden of mortality is only likely to worsen with the growing impact of human immunodeficiency virus (HIV)? It is estimated that around 4 million children under the age of 5 die annually from acute respiratory tract infections, and diarrhoeal diseases are responsible for approximately 3 million child deaths, while the contribution of HIV to child mortality is poorly quantified but growing? Mortality statistics need to be supplemented by estimates of the burden of disability (morbidity), and to allow for the varying implications of death at different ages. This can be done by use of disabilityadjusted life years (DALY): a measure developed by the World Bank and the World Health Organization (WHO).' Combining estimates of chronic disability and mortality statistics, this measure calculates the likely numbers of healthy years of life lost because of specific diseases and conditions. Also, by 'weighting', an allowance is made for the different significance of illhealth and mortality among infants, elderly persons compared to adults providing for dependants. Estimates of the burden of disease experienced emphasize the importance of infectious disease in developing countries, and the particular role in producing mortality in children under the age of 5 played