Fig. 3From: Vaccine-derived poliovirus surveillance in China during 2001–2013: the potential challenge for maintaining polio free statusGeographical distribution of VDPVs for AFP cases or healthy population by types of serotypes of poliovirus in China during 2001–2013. VDPV, vaccine-derived polioviruses; AFP, acute flaccid paralysis; healthy population, contacts of AFP cases or healthy subjects. The placement of the symbols for the geographical location of the VDPVs is random within each provinceBack to article page