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Human Vaccines & Immunotherapeutics 2018The emergence of vaccine-associated paralytic poliomyelitis has become an ongoing burden of poliomyelitis. During this special period from OPV to IPV-only immunization... (Comparative Study)
Comparative Study Meta-Analysis
Immunogenicity of sequential inactivated and oral poliovirus vaccines (OPV) versus inactivated poliovirus vaccine (IPV) alone in healthy infants: A systematic review and meta-analysis.
BACKGROUND
The emergence of vaccine-associated paralytic poliomyelitis has become an ongoing burden of poliomyelitis. During this special period from OPV to IPV-only immunization schedule, we did a meta-analysis to compare the immunogenicity of sequential IPV and OPV versus IPV alone in healthy infants.
METHODS
This systematic review and meta-analysis was registered at international prospective register of systematic reviews (PROSPERO), and the number was CRD42017054889. We performed it as described.
RESULTS
Finally, 6 articles were qualified for our review. The results showed that seroconversion rates against all 3 serotype polioviruses were non-inferior and Geometric mean antibody titers (GMTs) were superior in sequential schedules compared with IPV-only schedule. Thus, the sequential vaccination schedules could induce a stronger immunogenicity.
CONCLUSIONS
To decrease vaccine-associated and vaccine-derived poliomyelitis, it is a reasonable option to select sequential schedules during this special transition from OPV to IPV-only immunization schedule, which coincides with the current WHO recommendations.
Topics: Antibodies, Viral; Humans; Immunization Schedule; Immunogenicity, Vaccine; Infant; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Inactivated; Poliovirus Vaccine, Oral; Seroconversion; Vaccination
PubMed: 29985751
DOI: 10.1080/21645515.2018.1489188 -
Vaccine Mar 2018Widespread administration of oral poliovirus vaccine (OPV) has decreased global incidence of poliomyelitis by ≈99.9%. However, the emergence of vaccine-derived... (Meta-Analysis)
Meta-Analysis Review
Widespread administration of oral poliovirus vaccine (OPV) has decreased global incidence of poliomyelitis by ≈99.9%. However, the emergence of vaccine-derived polioviruses (VDPVs) is threatening polio-eradication program. Primary immunodeficiency (PID) patients are at higher risks of vaccine-associated paralytic poliomyelitis (VAPP) and prolonged excretion of immunodeficiency-associated VDPV (iVDPV). We searched Embase, Medline, Science direct, Scopus, Web of Science, and CDC and WHO databases by 30 September 2016, for all reports of iVDPV cases. Patient-level data were extracted form eligible studies. Data on immunization coverage and income-level of countries were extracted from WHO/UNICEF and the WORLD BANK databases, respectively. We assessed bivariate associations between immunological, clinical, and virological parameters, and exploited multivariable modeling to identify independent determinants of poliovirus evolution and patients' outcomes. Study protocol was registered with PROSPERO (CRD42016052931). 4329 duplicate-removed titles were screened. A total of 107 iVDPV cases were identified from 68 eligible articles. The majority of cases were from higher income countries with high polio-immunization coverage. 74 (69.81%) patients developed VAPP. Combined immunodeficiency patients showed lower rates of VAPP (p < .001) and infection clearance (p = .02), compared to humoral immunodeficiency patients. The rate of poliovirus genomic evolution was higher at early stages of replication, decreasing over time until reaching a steady state. Independent of replication duration, higher extent (p = .04) and rates (p = .03) of genome divergence contributed to a less likelihood of virus clearance. PID type (p < .001), VAPP occurrence (p = .008), and income-level of country (p = .04) independently influenced patients' survival. With the use of OPV, new iVDPVs will emerge independent of the rate of immunization coverage. Inherent features of PIDs contribute to the clinical course of iVDPV infection and virus evolution. This finding could shed further light on poliomyelitis pathogenesis and iVDPV evolution pattern. It also has implications for public health, the polio eradication effort and the development of effective antiviral interventions.
Topics: Animals; Child, Preschool; Female; History, 20th Century; History, 21st Century; Humans; Immunocompromised Host; Immunologic Deficiency Syndromes; Infant; Male; Odds Ratio; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Oral; Poliovirus Vaccines; Proportional Hazards Models; Serogroup; Vaccination
PubMed: 29478755
DOI: 10.1016/j.vaccine.2018.02.059 -
Journal of Medical Virology Jan 2018Acute flaccid paralysis (AFP), as defined by the World Health Organization (WHO), is characterized by an acute onset of limb weakness. In the post-polio era, other... (Review)
Review
Acute flaccid paralysis (AFP), as defined by the World Health Organization (WHO), is characterized by an acute onset of limb weakness. In the post-polio era, other enterovirus (EV) serotypes associated with AFP may become more prominent. This study aims to collate the data on the non-polio enteroviruses (NPEV) associated with AFP. A systematic review of published case reports, case series, and surveillance studies of AFP from 1960 through 2017 was undertaken. Data were collected including the country of the study, number of specimens positive for NPEV and available clinical data. The majority of studies originated from Asia. In surveillance studies, EV 71 (a serotype of Enterovirus A) was the most commonly detected serotype with AFP, followed by Enterovirus B serotype echovirus 11 and then Enterovirus B serotype echovirus 11. In case studies and case reports, EV 71 and EV 68 (a serotype of Enterovirus D), were the most commonly detected NPEV. As poliovirus eradication continues, there is a need to ensure that AFP surveillance will also detect other potentially vaccine preventable viruses.
Topics: Adolescent; Adult; Asia; Child; Child, Preschool; Enterovirus A, Human; Enterovirus B, Human; Enterovirus D, Human; Enterovirus Infections; Feces; Female; Humans; Male; Nucleic Acid Amplification Techniques; Paraplegia; Phylogeny; Poliovirus; Serogroup
PubMed: 28857219
DOI: 10.1002/jmv.24933 -
BMJ Open Jul 2017Accurate prevalence figures estimating the number of survivors of poliomyelitis (disease causing acute flaccid paralysis) following poliovirus infection are not... (Review)
Review
BACKGROUND
Accurate prevalence figures estimating the number of survivors of poliomyelitis (disease causing acute flaccid paralysis) following poliovirus infection are not available. We aim to undertake a systematic review of all literature concerning the prevalence of survivors of poliomyelitis.
METHODS
Electronic databases were searched from 1900 up to May 2016 for peer-reviewed studies using a population-based approach witha defined denominator and some form of diagnostic or clinical verification of polio. Exclusion criteria were any prevalence data that were unable to be extracted or calculated and studies reporting on incidence only. The quality of each included study was assessed using an existing tool modified for use in prevalence studies. Average crude prevalence rates were used to calculate worldwide estimates.
RESULTS
Thirty-one studies met criteria with 90% of studies conducted in low-income to lower middle-income countries. Significant variability in the prevalence of survivors of poliomyelitis was revealed, in low- income to lower middle-income (15 per 100 000 in Nigeria to 1733 in India) and upper-middle to high-income countries (24 (Japan) to 380 per 100 000 (Brazil). The total combined prevalence of survivors of poliomyelitis for those studies at low to moderate risk of bias ranged from 165 (high-income countries) to 425 (low-income to lower middle-income countries) per 100 000 person-years. Historical lameness surveys of children predominated, with wide variation in case definition and assessment criteria, and limited relevance to current prevalence given the lack of incidence of poliovirus infection in the ensuing years.
CONCLUSIONS
These results highlight the need for future epidemiological studies of poliomyelitis to examine nationally representative samples, including all ages and greater focus on high-income countries. Such efforts will improve capacity to provide reliable and more robust worldwide prevalence estimates.
Topics: Global Health; Humans; Incidence; Income; Internationality; Poliomyelitis; Survivors
PubMed: 28694346
DOI: 10.1136/bmjopen-2016-015470 -
Food and Environmental Virology Dec 2017Poliovirus surveillance plays a critical role in achieving and certifying eradication and will play a key role in the polio endgame. Environmental surveillance can... (Review)
Review
Poliovirus surveillance plays a critical role in achieving and certifying eradication and will play a key role in the polio endgame. Environmental surveillance can provide an opportunity to detect circulating polioviruses prior to the observation of any acute flaccid paralysis cases. We completed a systematic review of peer-reviewed publications on environmental surveillance for polio including the search terms "environmental surveillance" or "sewage," and "polio," "poliovirus," or "poliomyelitis," and compared characteristics of the resulting studies. The review included 146 studies representing 101 environmental surveillance activities from 48 countries published between 1975 and 2016. Studies reported taking samples from sewage treatment facilities, surface waters, and various other environmental sources, although they generally did not present sufficient details to thoroughly evaluate the sewage systems and catchment areas. When reported, catchment areas varied from 50 to over 7.3 million people (median of 500,000 for the 25% of activities that reported catchment areas, notably with 60% of the studies not reporting this information and 16% reporting insufficient information to estimate the catchment area population size). While numerous studies reported the ability of environmental surveillance to detect polioviruses in the absence of clinical cases, the review revealed very limited information about the costs and limited information to support quantitative population effectiveness of conducting environmental surveillance. This review motivates future studies to better characterize poliovirus environmental surveillance systems and the potential value of information that they may provide in the polio endgame.
Topics: Environmental Monitoring; Fresh Water; Humans; Poliomyelitis; Poliovirus; Sewage
PubMed: 28687986
DOI: 10.1007/s12560-017-9314-4 -
Vaccine Oct 2016Important investments were made in countries for the polio eradication initiative. On 25 September 2015, a major milestone was achieved when Nigeria was removed from the... (Review)
Review
BACKGROUND
Important investments were made in countries for the polio eradication initiative. On 25 September 2015, a major milestone was achieved when Nigeria was removed from the list of polio-endemic countries. Routine Immunization, being a key pillar of polio eradication initiative needs to be strengthened to sustain the gains made in countries. For this, there is a huge potential on building on the use of polio infrastructure to contribute to RI strengthening.
METHODS
We reviewed estimates of immunization coverage as reported by the countries to WHO and UNICEF for three vaccines: BCG, DTP3 (third dose of diphtheria-tetanus toxoid- pertussis), and the first dose of measles-containing vaccine (MCV1).We conducted a systematic review of best practices documents from eight countries which had significant polio eradication activities.
RESULTS
Immunization programmes have improved significantly in the African Region. Regional coverage for DTP3 vaccine increased from 51% in 1996 to 77% in 2014. DTP3 coverage increased >3 folds in DRC (18-80%) and Nigeria from 21% to 66%; and >2 folds in Angola (41-87%), Chad (24-46%), and Togo (42-87%). Coverage for BCG and MCV1 increased in all countries. Of the 47 countries in the region, 18 (38%) achieved a national coverage for DTP3 ⩾90% for 2years meeting the Global Vaccine Action (GVAP) target. A decrease was noted in the Ebola-affected countries i.e., Guinea, Liberia and Sierra Leone.
CONCLUSIONS
PEI has been associated with increased spending on immunization and the related improvements, especially in the areas of micro planning, service delivery, program management and capacity building. Continued efforts are needed to mobilize international and domestic support to strengthen and sustain high-quality immunization services in African countries. Strengthening RI will in turn sustain the gains made to eradicate poliovirus in the region.
Topics: Africa; BCG Vaccine; Diphtheria-Tetanus-Pertussis Vaccine; Disease Eradication; Global Health; Humans; Immunization Programs; Measles Vaccine; Nigeria; Poliomyelitis; Poliovirus Vaccine, Oral; Practice Guidelines as Topic; Togo; United Nations; Vaccination Coverage; World Health Organization
PubMed: 27396492
DOI: 10.1016/j.vaccine.2016.05.062 -
Vaccine May 2016Despite the significant decline in the incidence of vaccine-preventable diseases as a result of increased vaccination coverage worldwide, there are many children with... (Review)
Review
BACKGROUND
Despite the significant decline in the incidence of vaccine-preventable diseases as a result of increased vaccination coverage worldwide, there are many children with delayed vaccination and a marked heterogeneity in vaccination coverage.
OBJECTIVE
The aim of this study was to review factors that influence the adherence to childhood immunization schedule in different countries, especially related to socioeconomic conditions and health care system characteristics.
METHODS
Pubmed and Web of Science databases were searched systematically for observational studies published in peer-reviewed journals in English, Spanish and Portuguese languages from January 1992 to June 2014. We included original articles that assessed vaccination schedule with at least three diphtheria-tetanus-pertussis, three polio and one measles vaccines in children aged 0-24 months.
RESULTS
491 articles were identified and 23 met the inclusion criteria and were reviewed. The most cited factors reported by countries with distinct characteristics were higher birth order (9 articles, 39.1%), and low maternal education/socioeconomic status (7 articles each one, 30.4%). Irregular monitoring by the health care services was reported by countries with "mainly private" health care system. Out-of-hospital birth, no reminder(s) about the next follow-up visit, and mother working outside the home were cited by countries with low/medium Human Development Index (HDI). Ethnicity, use of private health care services, and no health insurance were cited by countries with very high HDI. The role of migration on vaccination coverage was reported by three studies conducted in countries with distinct characteristics.
CONCLUSIONS
The factors are complex and driven by context. Overall, strengthening the contacts and relationships between the health care services and mothers with several children and families with low educational level/low socioeconomic status appear to be an important action to improve vaccination coverage.
Topics: Birth Order; Diphtheria-Tetanus-Pertussis Vaccine; Educational Status; Health Services; Humans; Immunization Programs; Infant; Measles Vaccine; Poliovirus Vaccines; Socioeconomic Factors; Vaccination
PubMed: 27109562
DOI: 10.1016/j.vaccine.2016.04.016 -
Human Vaccines & Immunotherapeutics 2015The WHO European Region has been declared polio-free since 2002. By 2010, inactivated polio vaccine (IPV) was the only polio vaccine in use in the EU/EEA for the primary... (Review)
Review
The WHO European Region has been declared polio-free since 2002. By 2010, inactivated polio vaccine (IPV) was the only polio vaccine in use in the EU/EEA for the primary vaccination of children. A systematic review of the literature on polio seroprevalence studies, complemented by the analysis of available vaccine coverage data, has been carried out with the aim of assessing the level of protection against polio in the European population. A total of 52 studies, with data from 14 out of the 31 EU/EEA countries, were included in the analysis. This systematic review shows that, overall, seroprevalence for PV1 and PV3 is high in most countries, although seroimmunity gaps have been detected in several birth cohorts. In particular, relatively low immunity status was found in some countries for individuals born in the 60's and 70's. Discrepancies between reported vaccination coverage and immunity levels have been also highlighted. Countries should make sure that their population is being vaccinated for polio to reduce the risk of local poliovirus transmission in case of importation. Moreover, assessing immunity status should be priority for those traveling to areas where wild polioviruses are still circulating.
Topics: Antibodies, Viral; European Union; Humans; Poliomyelitis; Poliovirus; Seroepidemiologic Studies
PubMed: 25898095
DOI: 10.1080/21645515.2015.1016673 -
Vaccine Mar 2015Vaccine-derived polioviruses (VDPVs), strains of poliovirus mutated from the oral polio vaccine, pose a challenge to global polio eradication. Immunodeficiency-related... (Review)
Review
BACKGROUND
Vaccine-derived polioviruses (VDPVs), strains of poliovirus mutated from the oral polio vaccine, pose a challenge to global polio eradication. Immunodeficiency-related vaccine-derived polioviruses (iVDPVs) are a type of VDPV which may serve as sources of poliovirus reintroduction after the eradication of wild-type poliovirus. This review is a comprehensive update of confirmed iVDPV cases published in the scientific literature from 1962 to 2012, and describes clinically relevant trends in reported iVDPV cases worldwide.
METHODS
We conducted a systematic review of published iVDPV case reports from January 1960 to November 2012 from four databases. We included cases in which the patient had a primary immunodeficiency, and the vaccine virus isolated from the patient either met the sequencing definition of VDPV (>1% divergence for serotypes 1 and 3 and >0.6% for serotype 2) and/or was previously reported as an iVDPV by the World Health Organization.
RESULTS
We identified 68 iVDPV cases in 49 manuscripts reported from 25 countries and the Palestinian territories. 62% of case patients were male, 78% presented clinically with acute flaccid paralysis, and 65% were iVDPV2. 57% of cases occurred in patients with predominantly antibody immunodeficiencies, and the overall all-cause mortality rate was greater than 60%. The median age at case detection was 1.4 years [IQR: 0.8, 4.5] and the median duration of shedding was 1.3 years [IQR: 0.7, 2.2]. We identified a poliovirus genome VP1 region mutation rate of 0.72% per year and a higher median percent divergence for iVDPV1 cases. More cases were reported from high income countries, which also had a larger age variation and different distribution of immunodeficiencies compared to upper and lower middle-income countries.
CONCLUSION
Our study describes the incidence and characteristics of global iVDPV cases reported in the literature in the past five decades. It also highlights the regional and economic disparities of reported iVDPV cases.
Topics: Capsid Proteins; Disease Eradication; Female; Humans; Immunologic Deficiency Syndromes; Male; Mutation Rate; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Oral; Vaccination
PubMed: 25600519
DOI: 10.1016/j.vaccine.2015.01.018 -
The Journal of Infectious Diseases Sep 2014The impaired immunogenicity of oral poliovirus vaccine (OPV) in low-income countries has been apparent since the early field trials of this vaccine. Infection with... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The impaired immunogenicity of oral poliovirus vaccine (OPV) in low-income countries has been apparent since the early field trials of this vaccine. Infection with enteropathogens at the time of vaccination may contribute to this phenomenon. However, the relative influence of these infections on OPV performance remains uncertain.
METHODS
We conducted a systematic review to examine the impact of concurrent enteric infections on OPV response. Using random-effects models, we assessed the effects of nonpolio enteroviruses (NPEVs) and diarrhea on the odds of seroconversion and/or vaccine virus shedding.
RESULTS
We identified 25 trials in which OPV outcomes were compared according to the presence or absence of enteric infections, the majority of which (n = 17) reported only on NPEVs. Concurrent NPEVs significantly reduced the odds of per-dose seroconversion for type 1 poliovirus (odds ratio [OR] 0.44, 95% confidence interval 0.23-0.84), but not type 2 (OR 0.53 [0.19-1.46]) or type 3 (OR 0.56 [0.27-1.12]). A similar reduction, significant for type 1 poliovirus (OR 0.50 [0.28-0.89]), was observed in the odds of vaccine virus shedding among NPEV-infected individuals. Concurrent diarrhea significantly inhibited per-dose seroconversion overall (OR 0.61 [0.38-0.87]).
CONCLUSIONS
Our findings are consistent with an inhibitory effect of concurrent enteric infections on OPV response.
Topics: Diarrhea; Enterovirus Infections; Humans; Poliovirus; Poliovirus Vaccine, Oral; Virus Shedding
PubMed: 24688069
DOI: 10.1093/infdis/jiu182