We found a matchYour institution may have access to this item. Find your institution then sign in to continue.TitleUpdate on vaccine-derived polioviruses--worldwide, January 2008-June 2009.AuthorsCenters for Disease Control and Prevention (CDC)PublicationMMWR. Morbidity and mortality weekly report, 2009, Vol 58, Issue 36, p1002ISSN1545-861xPublication typearticle