Eradication of wild poliovirus from the Americas: wild poliovirus surveillance--laboratory issues.

The Pan American Regional Poliomyelitis Laboratory Network, developed to support the program to eradicate indigenous wild poliovirus transmission in the Americas, included 10 laboratories, distributed in eight countries in the Americas, organized according to the diagnostic procedures they regularly performed. All laboratories isolated and typed virus in stool specimens, several did intratypic differentiation by nucleic acid probe hybridization, and 2 sequenced wild poliovirus isolates for molecular epidemiologic studies. High performance of the network was maintained through comprehensive training of virologists, continuous monitoring of laboratory performance, and prompt investigation of problems. Recommended field and laboratory procedures were regularly reviewed and revised to optimize sensitivity, specificity, and diagnostic efficiency. Close integration of field and laboratory surveillance was achieved through frequent meetings between virologists and epidemiologists, effective communication of program priorities, and the distribution of weekly surveillance reports.