Transmission of imported vaccine-derived poliovirus in an undervaccinated community in Minnesota.
BACKGROUND
Oral poliovirus vaccine (OPV) has not been used in the United States since 2000. Type 1 vaccine-derived poliovirus (VDPV) was identified in September 2005, from an unvaccinated Amish infant hospitalized in Minnesota with severe combined immunodeficiency. An investigation was conducted to determine the source of the virus and its means of transmission.


METHODS
The infant was tested serially for poliovirus excretion. Investigations were conducted to detect poliovirus infections or paralytic poliomyelitis in Amish communities in Minnesota, neighboring states, and Ontario, Canada. Genomic sequences of poliovirus isolates were determined for phylogenetic analysis.


RESULTS
No source for the VDPV could be identified. In the index community, 8 (35%) of 23 children tested, including the infant, had evidence of type 1 poliovirus or VDPV infection. Phylogenetic analysis suggested that the VDPV circulated in the community for approximately 2 months before the infant's infection was detected and that the initiating OPV dose had been given before her birth. No paralytic disease was found in the community, and no poliovirus infections were found in other Amish communities investigated.


CONCLUSIONS
This is the first demonstrated transmission of VDPV in an undervaccinated community in a developed country. Continued vigilance is needed in all countries to identify poliovirus infections in communities at high risk of poliovirus transmission.
Alexander
James P
JP
National Center for Immunizations and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA. axj1@cdc.gov
Ehresmann
Kristen
K
Seward
Jane
J
Wax
Gary
G
Harriman
Kathleen
K
Fuller
Susan
S
Cebelinski
Elizabeth A
EA
Chen
Qi
Q
Jorba
Jaume
J
Kew
Olen M
OM
Pallansch
Mark A
MA
Oberste
M Steven
MS
Schleiss
Mark
M
Davis
Jeffrey P
JP
Warshawsky
Bryna
B
Squires
Susan
S
Hull
Harry F
HF
D000293:Adolescent; D000595:Amino Acid Sequence; D000956:Antigens, Viral / Q000737:chemistry / Q000235:genetics; D016026:Bone Marrow Transplantation; D002675:Child, Preschool; D005243:Feces / Q000821:virology; D005260:Female; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use; D007223:Infant; D008910:Minnesota; D010802:Phylogeny; D011051:Poliomyelitis / Q000517:prevention & control / Q000635:transmission* / Q000821:virology; D017955:Poliovirus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D023321:Poliovirus Vaccines / Q000008:administration & dosage* / Q000276:immunology; D016511:Severe Combined Immunodeficiency / Q000150:complications* / Q000628:therapy; D013997:Time Factors
D000956:Antigens, Viral; D016756:Immunoglobulins, Intravenous; D023321:Poliovirus Vaccines