Amino acid sequence within or near the NAg sites of the capsid protein VP1 in the type 1 VDPV isolated in sewage water samples in Tuxtla Gutiérrez, in comparison with other VDPVs, Sabin oral poliovirus vaccine virus, and wild poliovirus (Mahoney). The type 1 VDPV sequence is aligned with the Sabin 1 oral poliovirus vaccine, Mahoney (the neurovirulent wild-type poliovirus type 1 that is used as a seed strain for inactivated poliovirus), and 4 cVDPV isolates from the cVDPV1 outbreak in the Dominican Republic (DOR00016 and DOR00041c2) and Haiti (HIA00003 and HAI01007) in 2000 and 2001. Single-letter codes are used for amino acid residues. The numbers above the alignment reflect the amino acid locations; the first digit indicates the capsid protein VP1 and the next 3 digits indicate the amino acid position in the VP1 protein. Abbreviations: cVDPV, circulating vaccine-derived polioviruses; Nag, neutralizing antigenic; VDPV, vaccine-derived poliovirus; VP1, viral capsid protein 1.