Environmental Contributions to the Leading Causes of Disease Burden Among Australian Children

Abstract

lthough the effect of adverse environments on the well-beingof children is an important global health issue, it remainsunderrecognized in health care (1) and underconsidered in terms ofboth research and public policy. Children have developmentallydistinctpatterns ofenvironmental exposure andsusceptibilities thatincrease their risk of disease. Young children, especially thosewho are impoverished, have disproportionately heavier exposuresto environmental threats in a given environment. They alsohave decreased metabolic capacity to detoxify and eliminatecontaminants. Furthermore, rapid growth and development beforeand after birth and the continuing growth and postnatal maturationof the respiratory, immune, and neurological systems, in particular,make them increasingly vulnerable to environmental threats (2).There is emerging evidence that the origins of many adultdiseases are found during fetal development and early childhood(3). These early environmental exposures can affect adulthealth either by cumulative damage over time or by the biologicalembedding of adversities during sensitive developmental periods(4). It is also important to recognize that for children, exposure tolifestyleriskfactorssuchasdietandtobaccosmokearenotlifestylechoices but rather environmental exposures imposed on themby others. In spite of Australia’s high standard of living, Australianchildren do experience health consequences of adverse environ-mental exposures.A major gap in health outcomes and life expectancy existsin Australia between Indigenous and non-Indigenous populations(5,6). The colonization of Australia involved a series of unjustand misguided policies against Aboriginal and Torres StraitIslander peoples that led to disruption of social systems, disposses-sion of land, economic exploitation, discrimination, and culturaldevastation, resulting in severe inequalities in health status (5,6).Aboriginal and Torres Strait Islander children and young peopleinAustraliaaccount for4.2%ofthe Australianpopulationages 0to24 years. Children younger than 14 years comprise 38% of theAboriginal and Torres Strait Islander population, compared with19% of the non-Indigenous population. Almost one-third ofAboriginal and Torres Strait Islander children and youth (32%)live in major cities, 44% live in regional Australia, and almost one-fourth (24%) live in remote Australia (7). The health of Indigenouschildren, especially those in regional and remote communities,remains seriously compromised by a combination of socialdisadvantage, inadequate housingandovercrowding, poorhygiene,malnutrition, environmental contamination, and prevalent infec-tions (8).Aboriginal people living in remote communities in theNorthern Territory are the most disadvantaged group in Australiaaccording to all measurable determinants of health (9). In theselocations young children live in highly contaminated home andcommunity environments (10–12). When respiratory, skin, andgastrointestinal tract infections are endemic, extremely youngchildren are at an additional risk because of their exploratorybehavior and because they are dependent on others for their care.Most infection is transmitted primarily by direct person-to-personcontact or contact with contaminated fomites or animals (13,14).The situation is worsened by microbial contamination of foodand water. The high prevalence of hand contamination in remotecommunities is a result of frequent inoculation rather than longbacterial survival times (14).Infants and young children living in remote Aboriginalcommunities in the Northern Territory experience a high burdenof infection (15–17). An Indigenous infant between 4 weeks and1 year old is 7 to 8 times more likely to be admitted to hospital thana non-Indigenous child of the same age, particularly for gastro-intestinal tract and respiratory infections, with common comor-bidity (16). The median number of presentations per child in 1 yearfor 1 remote clinic was 16 (23 in the first year of life) (18).About 15% of Aboriginal children younger than 5 years inAustralia’s Northern Territory are underweight, 11% are stunted,and 9% are wasted (19). Important in the causal pathway leading topoor nutritional status is the malnutrition–infection cycle, wherebychildren who are underweight are at increased risk for infectiousdiseases such as diarrhea and respiratory infections and at sub-stantially increased risk for mortality. Gastrointestinal andparasiticinfestations are particularly important because of their damagingeffects on intestinal digestion and absorption of nutrients, minerals,and vitamins. The simultaneous presence of undernutrition andinfection significantly increases the risk of child mortality, withextended duration of diarrheal infections among malnourishedchildren playing an important role.The pattern of disease, however, is changing and for youngIndigenous and non-Indigenous Australians obesity has emergedas an increasingly important threat. After tobacco, obesity is the