Final answer:
The world's greatest cause of mortality and ill health in low-income countries, as reported by the WHO, includes acute respiratory infections, diarrhea, malaria, and other infectious diseases, with malnutrition being a significant contributing factor. In high-income countries, cancer, obesity, and mental illness are among the top causes of death, with unequal access to clean water and sanitation resources being a primary issue for low-income nations.
Step-by-step explanation:
According to the World Health Organization (WHO), the world's greatest cause of mortality, ill health, and suffering in low-income countries, especially for children under five, is attributed to factors such as acute respiratory infections, diarrheal diseases, and infectious diseases such as malaria. These conditions are primarily driven by environmental factors, including malnutrition, poor water quality, and inadequate sanitation conditions. Malnutrition and these environmental infections are closely interconnected, with a significant portion of malnutrition consequences arising from insufficient water supply and sanitation provisions coupled with substandard hygienic practices.
In high-income nations, on the other hand, the leading causes of death are linked to cancer, obesity, and mental illness, with a notable absence of deaths due to lack of clean water. The WHO also observes that while overall global life expectancy has increased, healthy life expectancy lags behind, growing less substantially. This observation signals that although people are living longer, they may not be experiencing extended periods of good health. Geographical variation also plays a significant role in the disparity of health outcomes with impoverished regions suffering more from health issues and having limited access to quality care.