Problems of preventive and social medicine.
D000349:Africa; D001294:Attitude to Health; D003140:Communicable Disease Control; D003906:Developing Countries; D004470:Economics, Medical; D004864:Equipment and Supplies; D006281:Health Occupations / Q000193:education; D006296:Health Services / Q000706:statistics & numerical data; D006801:Humans; D011315:Preventive Medicine; D012424:Rural Population; D012936:Social Medicine; D014505:Urban Population