Vaccine-Derived Poliovirus Infections Minnesota, 2005 Jim Alexander & Jane Seward National Vaccine Advisory Committee Washington, DC February 8, 2006
VDPV Investigations: USA & Canada
VDPV Investigations (1) Wisconsin: –Investigated 2 communities –Community A (grandparents): 13 stool specimens – all negative 6 serum specimens – 4 triple PV(+), 2 mixed –Community B: 4 stool specimens – all negative –Vaccinations offered – mixed response
VDPV Investigations (2) Michigan: –Identified Amish communities – “thumb” area –Families refused to give clinical specimens –Only 2 families initiated vaccination Missouri: –Identify Amish communities – NW Missouri –Bride & groom visited family & returned to Canada –Families refused to give clinical specimens –Little/no response to vaccination Iowa: –Vaccine coverage assessments – Amish
VDPV Investigations (3) Canada: –Investigated Amish community – SW Ontario October wedding & MN community contact –159 people in 24 families –41 persons: stool and/or throat swab All 36 stools & 5 unique throat swabs = PV (-) 2 stools = Coxsackie A2 (+) –>17 persons received 1 dose IPV Additional doses being offered –Post-wedding disease & infection surveillance
VDPV Investigations (4) CDC, National Immunization Program: –Coordination with states & Canada (CSTE) –Communication with other federal & international agencies – e.g. FDA, PAHO & WHO Geneva –Notification of state immunization partners, clinicians, & public – MMWR, press releases, alerts –Immunization Safety Office & MN collaboration: vaccine acceptance study FDA, Office of Blood Research: –Helped obtain PV1 high-titered IGIV
Conclusions VDPV: No known spread beyond central MN Amish community Well-coordinated response -- state, federal, other Sufficient supply of IPV for response –No need to access a stockpile Community acceptance of investigation = mixed –Good relationship with local HD >> better response –No paralytic disease >> lower sense of risk & response –Media attention >> disturbed privacy & adversely affected cooperation
Lessons Learned Current surveillance strategy = not optimal –Surveillance for paralytic poliomyelitis, not AFP –Poliovirus infections not notifiable Optimal control strategy = multifactorial –Sensitive surveillance & rapid response –Better understanding of perceptions of disease risk & vaccination benefit among under-vaccinated groups –Balance between public/media right to know & community’s right to privacy
Global Issues Increased recognition of risks of OPV use –Recent cVDPV outbreaks: Indonesia, Madagascar –Vaccine-Associated Paralytic Polio (VAPP) cases USA: 1 st documented imported VAPP case – 2005 Evolving WHO strategies for polio eradication: –Use of mOPV for final eradication efforts –Risk considerations in developing stockpile & outbreak response post-eradication: mOPV, IPV, antiviral drug WHO policies, strategies & products will influence US polio outbreak response & stockpile
U.S. Polio Vaccine Stockpile: IPV Recommended: 8 million doses Current status: ~3.5 million doses –Financing/accounting barriers to 8M dose goal Future directions: –Continue efforts to develop uncombined IPV stockpile through Pediatric Vaccine Stockpile –Consider other options for IPV stockpile?
U.S. Polio Vaccine Stockpile: Global Collaboration NVAC/ACIP Recommendation: –U.S. & partners: finance, create & maintain global PVS –Guaranteed & immediate U.S. access Global developments (since 2004): –Funding mechanism (IFFM) established for global PVS –Stockpile size: Initial: 750 million doses – each serotype (PV1, PV2, PV3) No doses stockpiled yet –Mechanisms for access being developed
U.S. Polio Vaccine Stockpile: OPV NVAC/ACIP Recommendation: –8 million doses; mOPV, if available Global Developments (since 2004): –Rapid progress in production, licensure & use of mOPV Sanofi-Pasteur: mOPV1 licensure (France & Egypt) GSK: mOPV1 licensure (Belgium, Pakistan & Egypt) –Use of mOPV1 in eradication efforts – Egypt & India Current status: –Work with WHO to select mOPV products –Develop IND for each product (serotype & company) –Explored EUA option – not applicable
Acknowledgements Minnesota HD & Lab –Harry Hull –Kris Ehresmann –Gary Wax –Kathy Harriman –Norman Crouch –John Besser –Susan Fuller FDA –Jonathan Goldsmith –Dorothy Scott Other Health Depts –Jeff Davis (WI) –Dan Hofspenberger (WI) –Bao Ping Zhu (MO) –Harvey Marx (MO) –Joel Blostein (MI) Canada –Susan Squires –Salwa Bishay –Bryna Warshawsky
Additional Slides
Minnesota Investigation: Summary IC Amish infant infected with VDPV Virus circulated within infant’s community –Infant probably infected in community –No clinical disease from these infections No known spread outside community –No hospital transmission –No spread to other Amish communities – MN Source of virus = unknown –Origin: OPV recipient in country outside US & Canada –Proximal (likely): IC person (virus = iVDPV)