"Worker numbers and quality are positively associated with immunization coverage, outreach of primary care, and infant, child and maternal survival" "The quality of doctors and the density of their distribution have been shown to correlate with positive outcomes in cardiovascular diseases" "In health systems, (primary care) workers function as gatekeepers and navigators for the effective, or wasteful, application of all other resources such as drugs, vaccines and supplies" "there are currently 57 countries with critical shortages equivalent to a global deficit of 2.4 million doctors, nurses and midwives" "In many countries, the skills of limited yet expensive professionals are not well matched to the local profile of health needs" "...all countries suffer from maldistribution characterized by urban concentration and rural deficits" "Richer countries face a future of low fertility and large populations of elderly people, which will cause a shift towards chronic and degenerative diseases with high care demands" "Growing gaps will exert even greater pressure on the outflow of health workers from poorer regions"