Poliomyelitis surveillance.
D000569:Americas; D019049:Developed Countries; D003906:Developing Countries; D004194:Disease; D004467:Economics; D005069:Evaluation Studies as Topic; D006301:Health Services Needs and Demand; D009934:Organization and Administration; D011051:Poliomyelitis; D014777:Virus Diseases
Americas; Developed Countries; Developing Countries; Diseases; Economic Factors; Evaluation; Monitoring; Needs; Obstacles; Organization And Administration; Poliomyelitis--prevention and control; Viral Diseases