between infectious agents and human hosts) (McKeown and Record 1962). At the same time, however, modern medicines today can have a major impact on population health in low- and middle-income countries. Unlike the 19th century, many effective medicines are now available not only for malaria, tuberculosis (TB), and human immunodeficiency virus (HIV), but also for everyday respiratory, intestinal, and urological infections. And in low-income countries, such infections are major sources of mortality (table 1.1). As the “epidemiological transition” advances and chronic diseases become ever more important in these countries, the role of medicines in improving health status will increase. Examples include the use of insulin for diabetes, antidepressants for mental health, statins for high cholesterol, and antihypertensives for high blood pressure. Projections for 2030 indicate that the leading causes of death in low- and middle-income countries will increasingly resemble those in high-income countries (Mathers and Loncar 2006). Add in the tropical diseases (such as schistosomiasis, filariasis, and soil-transmitted helminths) that are major sources of morbidity, and the Table 1.1
Top 10 Causes of Death by Income Group, 2004 High-income countries
Low-income countries
Rank
Cause of death
% total deaths
Rank
Cause of death
% total deaths
1
Coronary heart disease
16.3
1
Lower respiratory infections
11.2
2
Stroke and other cerebrovascular diseases
9.3
2
Coronary heart disease
9.4
3
Trachea, bronchus, lung cancers
5.9
3
Diarrhoeal diseases
6.9
4
Lower respiratory infections
3.8
4
HIV/AIDS
5.7
5
Chronic obstructive pulmonary disease
3.5
5
Stroke and other cerebrovascular diseases
5.6
6
Alzheimer and other dementias
3.4
6
Chronic obstructive pulmonary disease
3.6
7
Colon and rectum cancers
3.3
7
Tuberculosis
3.5
8
Diabetes mellitus
2.8
8
Neonatal infections
3.4
9
Breast cancer
2.0
9
Malaria
3.3
10
Stomach cancer
1.8
10
Prematurity and low birth weight
3.2
Source: WHO 2008.
2
Pharmaceutical Reform