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Expert Review of Vaccines Jul 2020Over the last 20 years (2000-2019) the partners of the Global Polio Eradication Initiative (GPEI) invested in the development and application of mathematical models of... (Review)
Review
INTRODUCTION
Over the last 20 years (2000-2019) the partners of the Global Polio Eradication Initiative (GPEI) invested in the development and application of mathematical models of poliovirus transmission as well as economics, policy, and risk analyses of polio endgame risk management options, including policies related to poliovirus vaccine use during the polio endgame.
AREAS COVERED
This review provides a historical record of the polio studies published by the three modeling groups that primarily performed the bulk of this work. This review also systematically evaluates the polio transmission and health economic modeling papers published in English in peer-reviewed journals from 2000 to 2019, highlights differences in approaches and methods, shows the geographic coverage of the transmission modeling performed, identified common themes, and discusses instances of similar or conflicting insights or recommendations.
EXPERT OPINION
Polio modeling performed during the last 20 years substantially impacted polio vaccine choices, immunization policies, and the polio eradication pathway. As the polio endgame continues, national preferences for polio vaccine formulations and immunization strategies will likely continue to change. Future modeling will likely provide important insights about their cost-effectiveness and their relative benefits with respect to controlling polio and potentially achieving and maintaining eradication.
Topics: Disease Eradication; Global Health; Humans; Immunization Programs; Models, Economic; Models, Theoretical; Poliomyelitis; Poliovirus Vaccines; Risk Management; Vaccination
PubMed: 32741232
DOI: 10.1080/14760584.2020.1791093 -
Mayo Clinic Proceedings Feb 2020The US Advisory Committee on Immunization Practices recommends that infants beginning at birth receive several vaccines directed against a variety of infectious diseases... (Review)
Review
The US Advisory Committee on Immunization Practices recommends that infants beginning at birth receive several vaccines directed against a variety of infectious diseases that currently pose threats of morbidity and mortality to infants and those around them, including the 3-dose hepatitis B (HepB) series. The first dose is due at birth. This series protects against maternal-infant transmission of the HepB virus and against exposure the rest of the infant's life. At age 2 months infants are to receive not only their second dose of HepB vaccine but also a series of vaccines directed against diphtheria, tetanus, pertussis, pneumococcus, rotavirus, poliovirus, and Haemophilus influenzae type b. At 4 months, infants are to repeat those vaccines except for the HepB vaccine. At age 6 months infants are to finish the HepB series and receive the third doses of the other vaccines received at 2 and 4 months except for the rotavirus vaccine, depending on the brand used. Also, starting at 6 months, depending on the time of year, infants are to begin a 2-dose series against influenza separated by 28 days. Each of these vaccines is due at a time when the vaccine works to protect against an immediate risk and to provide long-term protection. These vaccine-preventable diseases vary in terms of the nature of exposure, the form of the morbidity, the risk of mortality, and the ability of routine vaccination to prevent or ameliorate harm.
Topics: Diphtheria-Tetanus-Pertussis Vaccine; Haemophilus Vaccines; Hepatitis B Vaccines; Humans; Immunization Schedule; Infant; Infant, Newborn; Pneumococcal Vaccines; Poliovirus Vaccines; Rotavirus Vaccines; United States; Vaccination
PubMed: 31879133
DOI: 10.1016/j.mayocp.2019.06.007 -
Risk Analysis : An Official Publication... Feb 2021Beginning in 2013, multiple local government areas (LGAs) in Borno and Yobe in northeast Nigeria and other parts of the Lake Chad basin experienced a violent insurgency...
Beginning in 2013, multiple local government areas (LGAs) in Borno and Yobe in northeast Nigeria and other parts of the Lake Chad basin experienced a violent insurgency that resulted in substantial numbers of isolated and displaced people. Northeast Nigeria represents the last known reservoir country of wild poliovirus (WPV) transmission in Africa, with detection of paralytic cases caused by serotype 1 WPV in 2016 in Borno and serotype 3 WPV in late 2012. Parts of Borno and Yobe are also problematic areas for transmission of serotype 2 circulating vaccine-derived polioviruses, and they continue to face challenges associated with conflict and inadequate health services in security-compromised areas that limit both immunization and surveillance activities. We model poliovirus transmission of all three serotypes for Borno and Yobe using a deterministic differential equation-based model that includes four subpopulations to account for limitations in access to immunization services and dynamic restrictions in population mixing. We find that accessibility issues and insufficient immunization allow for prolonged poliovirus transmission and potential undetected paralytic cases, although as of the end of 2019, including responsive program activities in the modeling suggest die out of indigenous serotypes 1 and 3 WPVs prior to 2020. Specifically, recent and current efforts to access isolated populations and provide oral poliovirus vaccine continue to reduce the risks of sustained and undetected transmission, although some uncertainty remains. Continued improvement in immunization and surveillance in the isolated subpopulations should minimize these risks. Stochastic modeling can build on this analysis to characterize the implications for undetected transmission and confidence about no circulation.
Topics: Child; Child, Preschool; Disease Outbreaks; Humans; Immunization Programs; Infant; Nigeria; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Inactivated; Poliovirus Vaccine, Oral; Poliovirus Vaccines; Risk Assessment; Vaccination
PubMed: 32348621
DOI: 10.1111/risa.13485 -
Biologicals : Journal of the... May 2018According to manufacturers, inactivated poliovirus vaccines (IPVs) are freeze sensitive and require storage between 2°C and 8°C, whereas oral poliovirus vaccine...
According to manufacturers, inactivated poliovirus vaccines (IPVs) are freeze sensitive and require storage between 2°C and 8°C, whereas oral poliovirus vaccine requires storage at -20 °C. Introducing IPV into ongoing immunization services might result in accidental exposure to freezing temperatures and potential loss of vaccine potency. To better understand the effect of freezing IPVs, samples of single-dose vaccine vials from Statens Serum Institut (VeroPol) and multi-dose vaccine vials from Sanofi Pasteur (IPOL) were exposed to freezing temperatures mimicking what a vaccine vial might encounter in the field. D-antigen content was measured to determine the in vitro potency by ELISA. Immunogenicity testing was conducted for a subset of exposed IPVs using the rat model. Freezing VeroPol had no detectable effect on in vitro potency (D-antigen content) in all exposures tested. Freezing of the IPOL vaccine for 7 days at -20 °C showed statistically significant decreases in D-antigen content by ELISA in poliovirus type 1 (p < 0.0001) and type 3 (p = 0.048). Reduction of poliovirus type 2 potency also approached significance (p = 0.062). The observed loss in D-antigen content did not affect immunogenicity in the rat model. Further work is required to determine the significance of the loss observed and the implications for vaccine handling policies and practices.
Topics: Animals; Cryopreservation; Female; Freezing; Immunogenicity, Vaccine; Poliovirus Vaccine, Inactivated; Rats; Rats, Wistar
PubMed: 29548791
DOI: 10.1016/j.biologicals.2018.03.002 -
Virus Research Jan 2022An 8-month-old child diagnosed with severe combined immunodeficiency (SCID) was found to be excreting vaccine-derived poliovirus (VDPVs). Five stool samples from the...
An 8-month-old child diagnosed with severe combined immunodeficiency (SCID) was found to be excreting vaccine-derived poliovirus (VDPVs). Five stool samples from the child and stool samples from 24 contacts were collected during the following 7 months. Complete genome sequence by next generation sequencing (NGS) identified 0.7 to 1.4% nucleotide substitutions in the capsid P1 region of the first and the last isolates compared with Sabin 3 strain. Simplot analysis revealed that all isolates were Sabin 3/Sabin 1 recombinants, sharing a single recombination breakpoint in the 2C region. Multiple nucleotide variants were identified in the 5'UTR (T→C and G→A); amino acid mutations were identified in residues at VP1-6 (Thr to Ile), VP1-105 (Met to Thr), VP1-286 (Arg to Lys), VP2-155 (Lys to Glu), VP3-59 (Ser to Asn) and VP3-91 (Phe to Ser). These variants were commonly observed in other PV strains, which may contribute to attenuation and temperature sensitivity. None of the 24 tested contacts of the patient and related transmits was found to be infected with poliovirus. Our study provides a rapid and reliable method for the characterization of VDPV research in Poliovirus infection. In post-OPV era, immunodeficient people with persistent and chronic infection remain a major challenge for polio eradication in China.
Topics: Child; Humans; Infant; Nucleotides; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Oral; Severe Combined Immunodeficiency; Vaccines, Synthetic
PubMed: 34793871
DOI: 10.1016/j.virusres.2021.198633 -
Annual Review of Virology Sep 2018Since the launch of the Global Polio Eradication Initiative (GPEI), paralytic cases associated with wild poliovirus (WPV) have fallen from ∼350,000 in 1988 to 22 in... (Review)
Review
Since the launch of the Global Polio Eradication Initiative (GPEI), paralytic cases associated with wild poliovirus (WPV) have fallen from ∼350,000 in 1988 to 22 in 2017. WPV type 2 (WPV2) was last detected in 1999, WPV3 in 2012, and WPV1 appeared to be localized to Pakistan and Afghanistan in 2017. Through continuous refinement, the GPEI has overcome operational and biological challenges far more complex and daunting than originally envisioned. Operational challenges had led to sustained WPV endemicity in core reservoirs and widespread dissemination to polio-free countries. The biological challenges derive from intrinsic limitations to the oral poliovirus vaccine: ( a) reduced immunogenicity in high-risk settings and ( b) genetic instability, leading to repeated outbreaks of circulating vaccine-derived polioviruses and prolonged infections in individuals with primary immunodeficiencies. As polio eradication enters its multifaceted endgame, the GPEI, with its technical, operational, and social innovations, stands as the preeminent model for control of vaccine-preventable diseases worldwide.
Topics: Communicable Disease Control; Disease Eradication; Disease Transmission, Infectious; Drug Stability; Global Health; Humans; Poliomyelitis; Poliovirus Vaccines
PubMed: 30001183
DOI: 10.1146/annurev-virology-101416-041749 -
Nature Immunology Jun 2017
Topics: Allergy and Immunology; Cell Culture Techniques; History, 20th Century; History, 21st Century; Poliovirus Vaccines; Virology
PubMed: 28632716
DOI: 10.1038/ni.3779 -
The American Journal of Tropical... Nov 2023Combining oral (OPV) and inactivated (IPV) poliovirus vaccines prevents importation of poliovirus and emergence of circulating vaccine-derived poliovirus. We measured...
Combining oral (OPV) and inactivated (IPV) poliovirus vaccines prevents importation of poliovirus and emergence of circulating vaccine-derived poliovirus. We measured the coverage with IPV and third dose of OPV (OPV-3) and identified determinants of coverage inequality in the most at-risk populations in Ethiopia. A national survey representing 10 partly overlapping underserved populations-pastoralists, conflict-affected areas, urban slums, hard-to-reach settings, developing regions, newly formed regions, internally displaced people (IDPs), refugees, and districts neighboring international and interregional boundaries-was conducted among children 12 to 35 months old (N = 3,646). Socioeconomic inequality was measured using the concentration index (CIX) and decomposed using a regression-based approach. One-third (95% CI: 31.5-34.0%) of the children received OPV-3 and IPV. The dual coverage was below 50% in developing regions (19.2%), pastoralists (22.0%), IDPs (22.3%), districts neighboring international (24.1%) and interregional (33.3%) boundaries, refugees (27.0%), conflict-affected areas (29.3%), newly formed regions (33.5%), and hard-to-reach areas (38.9%). Conversely, coverage was better in urban slums (78%). Children from poorest households, living in villages that do not have health posts, and having limited health facility access had increased odds of not receiving the vaccines. Low paternal education, dissatisfaction with vaccination service, fear of vaccine side effects, living in female-headed households, having employed and less empowered mothers were also risk factors. IPV-OPV3 coverage favored the rich (CIX = -0.161, P < 0.001), and causes of inequality were: inaccessibility of health facilities (13.3%), dissatisfaction with vaccination service (12.8%), and maternal (4.9%) and paternal (4.9%) illiteracy. Polio vaccination coverage in the most at-risk populations in Ethiopia is suboptimal, threatening the polio eradication initiative.
Topics: Child, Preschool; Humans; Infant; Ethiopia; Poliomyelitis; Poliovirus Vaccine, Inactivated; Poliovirus Vaccine, Oral; Risk Factors; Vaccination
PubMed: 37748762
DOI: 10.4269/ajtmh.23-0319 -
The Lancet. Infectious Diseases Apr 2021Following the global eradication of wild poliovirus, countries using live attenuated oral poliovirus vaccines will transition to exclusive use of inactivated poliovirus...
BACKGROUND
Following the global eradication of wild poliovirus, countries using live attenuated oral poliovirus vaccines will transition to exclusive use of inactivated poliovirus vaccine (IPV) or fractional doses of IPV (f-IPV; a f-IPV dose is one-fifth of a normal IPV dose), but IPV supply and cost constraints will necessitate dose-sparing strategies. We compared immunisation schedules of f-IPV and IPV to inform the choice of optimal post-eradication schedule.
METHODS
This randomised open-label, multicentre, phase 3, non-inferiority trial was done at two centres in Panama and one in the Dominican Republic. Eligible participants were healthy 6-week-old infants with no signs of febrile illness or known allergy to vaccine components. Infants were randomly assigned (1:1:1:1, 1:1:1:2, 2:1:1:1), using computer-generated blocks of four or five until the groups were full, to one of four groups and received: two doses of intradermal f-IPV (administered at 14 and 36 weeks; two f-IPV group); or three doses of intradermal f-IPV (administered at 10, 14, and 36 weeks; three f-IPV group); or two doses of intramuscular IPV (administered at 14 and 36 weeks; two IPV group); or three doses of intramuscular IPV (administered at 10, 14, and 36 weeks; three IPV group). The primary outcome was seroconversion rates based on neutralising antibodies for poliovirus type 1 and type 2 at baseline and at 40 weeks (4 weeks after the second or third vaccinations) in the per-protocol population to allow non-inferiority and eventually superiority comparisons between vaccines and regimens. Three co-primary outcomes concerning poliovirus types 1 and 2 were to determine if seroconversion rates at 40 weeks of age after a two-dose regimen (administered at weeks 14 and 36) of intradermally administered f-IPV were non-inferior to a corresponding two-dose regimen of intramuscular IPV; if seroconversion rates at 40 weeks of age after a two-dose IPV regimen (weeks 14 and 36) were non-inferior to those after a three-dose IPV regimen (weeks 10, 14, and 36); and if seroconversion rates after a two-dose f-IPV regimen (weeks 14 and 36) were non-inferior to those after a three-dose f-IPV regimen (weeks 10, 14, and 36). The non-inferiority boundary was set at -10% for the lower bound of the two-sided 95% CI for the seroconversion rate difference.. Safety was assessed as serious adverse events and important medical events. This study is registered on ClinicalTrials.gov, NCT03239496.
FINDINGS
From Oct 23, 2017, to Nov 13, 2018, we enrolled 773 infants (372 [48%] girls) in Panama and the Dominican Republic (two f-IPV group n=217, three f-IPV group n=178, two IPV group n=178, and three IPV group n=200). 686 infants received all scheduled vaccine doses and were included in the per-protocol analysis. We observed non-inferiority for poliovirus type 1 seroconversion rate at 40 weeks for the two f-IPV dose schedule (95·9% [95% CI 92·0-98·2]) versus the two IPV dose schedule (98·7% [95·4-99·8]), and for the three f-IPV dose schedule (98·8% [95·6-99·8]) versus the three IPV dose schedule (100% [97·9-100]). Similarly, poliovirus type 2 seroconversion rate at 40 weeks for the two f-IPV dose schedule (97·9% [94·8-99·4]) versus the two IPV dose schedule (99·4% [96·4-100]), and for the three f-IPV dose schedule (100% [97·7-100]) versus the three IPV dose schedule (100% [97·9-100]) were non-inferior. Seroconversion rate for the two f-IPV regimen was statistically superior 4 weeks after the last vaccine dose in the 14 and 36 week schedule (95·9% [92·0-98·2]) compared with the 10 and 14 week schedule (83·2% [76·5-88·6]; p=0·0062) for poliovirus type 1. Statistical superiority of the 14 and 36 week schedule was also found for poliovirus type 2 (14 and 36 week schedule 97·9% [94·8-99·4] vs 10 and 14 week schedule 83·9% [77·2-89·2]; p=0·0062), and poliovirus type 3 (14 and 36 week schedule 84·5% [78·7-89·3] vs 10 and 14 week schedule 73·3% [65·8-79·9]; p=0·0062). For IPV, a two dose regimen administered at 14 and 36 weeks (99·4% [96·4-100]) was superior a 10 and 14 week schedule (88·9% [83·4-93·1]; p<0·0001) for poliovirus type 2, but not for type 1 (14 and 36 week schedule 98·7% [95·4-99·8] vs 10 and 14 week schedule 95·6% [91·4-98·1]), or type 3 (14 and 36 week schedule 97·4% [93·5-99·3] vs 10 and 14 week schedule 93·9% [89·3-96·9]). There were no related serious adverse events or important medical events reported in any group showing safety was unaffected by administration route or schedule.
INTERPRETATION
Our observations suggest that adequate immunity against poliovirus type 1 and type 2 is provided by two doses of either IPV or f-IPV at 14 and 36 weeks of age, and broad immunity is provided with three doses of f-IPV, enabling substantial savings in cost and supply. These novel clinical data will inform global polio immunisation policy for the post-eradication era.
FUNDING
Bill & Melinda Gates Foundation.
Topics: Antibodies, Viral; Dominican Republic; Female; Humans; Immunization Schedule; Immunogenicity, Vaccine; Infant; Infant, Newborn; Male; Panama; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Inactivated; Poliovirus Vaccine, Oral; Seroconversion
PubMed: 33284114
DOI: 10.1016/S1473-3099(20)30555-7 -
The Journal of Infectious Diseases Nov 2014Polio eradication requires the removal of all polioviruses from human populations, whether wild poliovirus or those emanating from the oral poliovirus vaccine (OPV). The... (Review)
Review
Polio eradication requires the removal of all polioviruses from human populations, whether wild poliovirus or those emanating from the oral poliovirus vaccine (OPV). The Polio Eradication & Endgame Strategic Plan 2013-2018 provides a framework for interruption of wild poliovirus transmission in remaining endemic foci and lays out a plan for the new polio end game, which includes the withdrawal of Sabin strains, starting with type 2, and the introduction of inactivated poliovirus vaccine, for risk mitigation purposes. This report summarizes the rationale and evidence that supports the policy decision to switch from trivalent OPV to bivalent OPV and to introduce 1 dose of inactivated poliovirus vaccine into routine immunization schedules, and it describes the proposed implementation of this policy in countries using trivalent OPV.
Topics: Disease Eradication; Global Health; Humans; Poliomyelitis; Poliovirus Vaccines; Vaccination
PubMed: 25316865
DOI: 10.1093/infdis/jiu222