Vaccine-associated Paralytic Polio Research Articles

Stem Cell Transplant in Immune-deficiency-associated Vaccine-derived Poliovirus.

Patients with severe primary immunodeficiency are at risk for complications from live-attenuated vaccines. Here, we report a case of a vaccine-associated paralytic polio and Bacille Calmette-Guérin disease in a 6-month-old girl with severe combined immunodeficiency resulting from homozygous recombinant activating gene 1 deficiency. The patient was successfully treated with intravenous immunoglobulins and oral pocapavir for poliovirus, and antimycobacterial therapy for regional Bacille Calmette-Guérin disease, allowing stem cell transplant. Following transplantation, poliovirus type 3 with 13 mutations was detected from cerebrospinal fluid but not from stool, indicating ongoing viral evolution in the central nervous system despite pocapavir treatment. Clinical improvement and immune reconstitution allowed the patient to be successfully discharged with no further detection of poliovirus.

Polio eradication: what kind of world do we want?

Achieving the 1988 World Health Assembly commitment of global eradication of poliomyelitis1 will require ending the transmission of all three types (1, 2, and 3) of wild polioviruses and use of oral poliovirus vaccine (OPV).2 Although extremely rare, OPV can cause vaccine-associated paralytic polio in immunologically naive recipients or close contacts upon first exposure.3 In addition, when used in populations with low immunisation coverage, OPV can continue to circulate, instead of dying out, and lose its attenuating mutations as it spreads.

The Pathology of Poliomyelitis and the Vaccines and Nonvaccine Therapy

Poliomyelitis is an exclusively human disease that mainly affects children. Clinical features of poliomyelitis can be varied, from mild illness to the most severe paralysis, and the factor why poliomyelitis has different performances in individuals has been proved strongly correlated with membrane protein CD155. The nervous system shows a special protecting phenomenon against the invasion of poliovirus, and the mechanism is not very clear at present. Vaccines are the main means of preventing and controlling polio, and many different vaccines have been invented in the process of fighting polio. Inactivated polio vaccine (IPV) and oral polio vaccine (OPV) are the two main vaccines. IPV is known for its safety while OPV is widely used in developing countries because of its relatively low cost. This usage also leads to some side effects: vaccine-associated paralytic polio (VAPP) and vaccine-derived poliovirus (VDPV). Now, for polio eradication, the elimination of these two diseases has become particularly important. Thus, a new type of vaccine was created: sequential IPV-OPV with the safety of IPV and the low cost of OPV. This paper will talk about the different polio vaccines and their effects. An enormous difference between people who have gotten the vaccine and people who have not got the vaccine. Comparing the two kinds of people, people who get normal poliovirus, and people who get poliovirus after taking a vaccine, known as VAPP (vaccine-associated paralytic poliomyelitis), the former cannot get full recovery whole life and the latter has a very low possibility. In conclusion, people should take vaccines if it is affordable for them.

Updated Characterization of Outbreak Response Strategies for 2019-2029: Impacts of Using a Novel Type 2 Oral Poliovirus Vaccine Strain.

Delays in achieving the global eradication of wild poliovirus transmission continue to postpone subsequent cessation of all oral poliovirus vaccine (OPV) use. Countries must stop OPV use to end all cases of poliomyelitis, including vaccine-associated paralytic polio (VAPP) and cases caused by vaccine-derived polioviruses (VDPVs). The Global Polio Eradication Initiative (GPEI) coordinated global cessation of all type 2 OPV (OPV2) use in routine immunization in 2016 but did not successfully end the transmission of type 2 VDPVs (VDPV2s), and consequently continues to use type 2 OPV (OPV2) for outbreak response activities. Using an updated global poliovirus transmission and OPV evolution model, we characterize outbreak response options for 2019-2029 related to responding to VDPV2 outbreaks with a genetically stabilized novel OPV (nOPV2) strain or with the currently licensed monovalent OPV2 (mOPV2). Given uncertainties about the properties of nOPV2, we model different assumptions that appear consistent with the evidence on nOPV2 to date. Using nOPV2 to respond to detected cases may reduce the expected VDPV and VAPP cases and the risk of needing to restart OPV2 use in routine immunization compared to mOPV2 use for outbreak response. The actual properties, availability, and use of nOPV2 will determine its effects on type 2 poliovirus transmission in populations. Even with optimal nOPV2 performance, countries and the GPEI would still likely need to restart OPV2 use in routine immunization in OPV-using countries if operational improvements in outbreak response to stop the transmission of cVDPV2s are not implemented effectively.

A Health Economic Analysis for Oral Poliovirus Vaccine to Prevent COVID-19 in the United States.

COVID‐19 led to a recent high‐profile proposal to reintroduce oral poliovirus vaccine (OPV) in the United States (U.S.), initially in clinical trials, but potentially for widespread and repeated use. We explore logistical challenges related to U.S. OPV administration in 2020, review the literature related to nonspecific effects of OPV to induce innate immunity, and model the health and economic implications of the proposal. The costs of reintroducing a single OPV dose to 331 million Americans would exceed $4.4 billion. Giving a dose of bivalent OPV to the entire U.S. population would lead to an expected 40 identifiable cases of vaccine‐associated paralytic polio, with young Americans at the highest risk. Reintroducing any OPV use in the U.S. poses a risk of restarting transmission of OPV‐related viruses and could lead to new infections in immunocompromised individuals with B‐cell related primary immunodeficiencies that could lead to later cases of paralysis. Due to the lack of a currently licensed OPV in the U.S., the decision to administer OPV to Americans for nonspecific immunological effects would require purchasing limited global OPV supplies that could impact polio eradication efforts. Health economic modeling suggests no role for reintroducing OPV into the U.S. with respect to responding to COVID‐19. Countries that currently use OPV experience fundamentally different risks, costs, and benefits than the U.S. Successful global polio eradication will depend on sufficient OPV supplies, achieving and maintaining high OPV coverage in OPV‐using countries, and effective global OPV cessation and containment in all countries, including the U.S.

Primary immunodeficiency masks: A clinical case of vaccine-associated paralytic poliomyelitis

Human inborn immune-related errors comprise a heterogeneous group of rare genetically determined diseases of the immune system caused by loss or gain of function mutations altering relevant protein functions. The 2019 International Union of Immunological Societies recently proposed the classification for such pathologies now comprising 406 distinct disorders with 430 different gene defects. Predominantly antibody deficiencies represent most common group of human inborn immune-related errors, which diagnostics poses uneasy challenge for general practitioner due to a broad range of their clinical manifestations, such as infection, allergy, autoimmunity and malignancy. In addition, patients with human immune-related inborn errors may develop a vaccine-associated disease after administering live vaccines in accordance with the Russia-wide National Vaccine Schedule. Most common among vaccine-associated diseases are vaccine-associated paralytic poliomyelitis, vaccine-associated encephalitis (1 case per 1 000 000 doses of measles, rubella, varicella vaccine), vaccine-associated meningitis (1 case per 250 000 – 500 000 doses of mumps vaccine) as well as adverse effects related to BCG immunization: local (infiltration, cold abscess – 8.6 case per 100,000 vaccinated patients) and disseminated complications (BCG lymphadenitis – 15.5 case per 100 000 vaccinated patients, BCG osteitis – 3.5 case per 100 000 vaccinated patients). Vaccine-associated paralytic poliomyelitis in vaccinated patients occurs after the first, second and rarely third oral polio vaccine dose inoculation. Incidence rate for vaccineassociated paralytic polio after 1 and 3 oral vaccine inoculation ranges from 1 case per 700 000 vaccine doses to 1 case per 3 500 000, respectively. Vaccine-associated paralytic poliomyelitis mainly emerges due to inborn mutations related to humoral immunity after primary vaccination with oral polio vaccine or close contact of unvaccinated patients with subjects vaccinated with oral polio vaccine. Here, we describe a clinical case of vaccine-associated paralytic poliomyelitis in patient with primary immunodeficiency. Our is aimed at emphasizing importance of immunological alertness with regard to detecting primary immunodeficiencies and timely apply a replacement therapy prior to verifying type of immunodeficiency.

Expected Implications of Globally Coordinated Cessation of Serotype 3 Oral Poliovirus Vaccine (OPV) Before Serotype 1 OPV.

Globally coordinated cessation of all three serotypes of oral poliovirus vaccine (OPV) represents a critical part of a successful polio endgame, which the Global Polio Eradication Initiative (GPEI) plans to conduct in phases, with serotype 2 OPV cessation completed in mid 2016. Although in 2016 the GPEI expected to globally coordinate cessation of the remaining OPV serotypes (1 and 3) by 2021, continuing transmission of serotype 1 wild polioviruses to date makes those plans obsolete. With increasing time since the last reported polio case caused by serotype 3 wild poliovirus (in November 2012) leading to high confidence about its successful global eradication, the Global Commission for the Certification of Poliomyelitis Eradication recently certified its eradication. Questions now arise about the optimal timing of serotype 3 OPV (OPV3) cessation. Using an integrated global model that characterizes the risks, costs, and benefits of global polio policy and risk management options, we explored the implications of different options for coordinated cessation of OPV3 prior to COVID-19. Globally coordinating cessation of OPV3 as soon as possible offers the opportunity to reduce cases of vaccine-associated paralytic polio globally. In addition, earlier cessation of OPV3 should reduce the risks of creating serotype 3 circulating vaccine-derived polioviruses after OPV3 cessation, which represents a significant threat to the polio endgame given current GPEI plans to reduce preventive OPV supplemental immunization activities starting in 2019.

Moving from oral poliovirus vaccine to inactivated poliovirus vaccine: The rationale and challenges

Oral polio vaccine (OPV) has served as the cornerstone of polio eradication efforts over the past 30 years, trivalent inactivated polio vaccine (IPV) has re-ascended to prominence in the past year, now acting as the sole source of protective immunity against type 2 poliovirus in routine immunization programmes. The Polio Eradication and Endgame Strategic plan 2013–2018, developed by the Global Polio Eradication Initiative (GPEI) outlines the phased removal of OPVs, starting with type 2 poliovirus–containing vaccines and introduction of inactivated polio vaccine in routine immunization to mitigate against risk of vaccine-associated paralytic polio and circulating vaccine-derived poliovirus.
 Bangladesh J Medicine Jan 2020; 31(1) : 22-28

Sequential inactivated (IPV) and live oral (OPV) poliovirus vaccines for preventing poliomyelitis.

Sequential inactivated (IPV) and live oral (OPV) poliovirus vaccines for preventing poliomyelitis.

The moral dilemma of the polio eradication programme.

During the last five years, globally, cases of polio caused by vaccine viruses have outnumbered those of polio caused by natural (wild) polioviruses, posing a moral dilemma. Public health ethics should ensure the best interests of the community, with equity in sharing benefits and risks irrespective of socioeconomic disparities. Vaccine viruses in oral polio vaccine (OPV) cause vaccine-associated paralytic polio (VAPP), while paralytic polio is also caused by vaccine-derived polioviruses (VDPVs). By its policy of the use of OPV in low and middle-income countries, while rich countries use the safe inactivated polio vaccine (IPV), the Global Polio Eradication Programme has been responsible for social injustice. In 2017 and 2018, there were outbreaks of polio in Syria and Papua New Guinea due to circulating VDPVs, after many years of these countries remaining free of polio due to wild polioviruses. The only ethical way forward for global polio eradication is to replace OPV with IPV in all countries.

1668. No Impact of Nutritional Status on Oral Polio Vaccine shedding after Vaccination of Under 5 Children in Rural Mexico

BackgroundAs wild poliovirus is nearing global eradication and countries switch from Oral Polio Vaccine (OPV) to Inactivated Polio Vaccine (IPV), preventing circulating vaccine-derived poliovirus is a top priority. However, the circulation of OPV serotypes remains a concern in undervaccinated communities. We sought to examine the relationship between pediatric nutritional status and OPV shedding based on length-for-age categorizations. Mexico provides a natural environment to study these patterns as it provides routine IPV immunization and bi-annual OPV campaigns.MethodsWe enrolled 466 households with children eligible for OPV before the February 2015 national health week from 3 semi-rural Indigenous communities near Orizaba, Mexico. In each community, a different proportion of eligible children received OPV (10%, 30%, 70%), with a total of 155 vaccinated children. OPV shedding was measured by RT-qPCR detection of OPV in samples collected serially over 10 weeks. Anthropometric measurements were collected and compared with the WHO Multicenter Growth Reference Study growth curves to assign stunting. Associations between stunting, OPV shedding, and shedding duration were tested by Fisher exact test and Wilcoxon-Man-Whitney Test (α = 0.05).ResultsSamples of fecal OPV isolates were collected over time and analyzed from 148 vaccinees. 25 (17%) of the vaccinees were stunted. There was no relationship between pediatric stunting and likelihood of ever shedding any serotype of OPV (P = 0.82). The mean duration of OPV shedding by stunted and non-stunted children differed, but not significantly (10.9 days vs. 9.3 days, respectively, P = 0.32). We did not find any statistically significant differences between stunting status and shedding of any individual OPV serotype.ConclusionFurther understanding of factors related to OPV shedding is necessary to approach efficient worldwide poliovirus control. We found no relationship between stunting status and both OPV shedding and shedding duration post-vaccination, suggesting that nutritional status does not play a role in OPV shedding. The ongoing analysis includes longitudinal analysis of OPV shedding patterns by nutritional status, and the impact of stunting on viral load and reversion of OPV to vaccine-associated paralytic polio mutants.Disclosures All authors: No reported disclosures.

Клиническая характеристика случаев вакциноассоциированного паралитического полиомиелита в Российской Федерации в 2006–2016 гг.

Клиническая характеристика случаев вакциноассоциированного паралитического полиомиелита в Российской Федерации в 2006–2016 гг.

Preventive Vaccination against Poliomyelitis: Modern View

Poliomyelitis is a typical anthroponosis, in natural conditions it infects only humans. The only effective strategy for combating the infection is preventive vaccination. The polio vaccine induces long-lasting humoral and local immunity. The article presents a brief history of polio vaccine development, and compares live and inactivated vaccines currently licensed and used in Russia. It also dwells upon the benefits and shortcomings of each of these vaccines. The results of analysis demonstrated that all foreign-made and domestically-produced polio vaccines currently used in Russia meet international requirements in terms of main quality characteristics and comply with the WHO recommendations. The article looks into some issues arising from the use of live polio vaccine, in particular the development of vaccine-associated paralytic polio, and the appearance of vaccine-derived polioviruses. It reviews the main approaches of the current WHO polio eradication initiative, and summarises the outcomes of the 30-year period since the adoption of the Global Polio Eradication Initiative. The article describes the transition from live attenuated oral polio vaccine (types 1, 2 and 3) to bivalent vaccine (live attenuated oral polio vaccine, types 1 and 3). It discusses the necessity of using polio vaccines (both live and inactivated) at the final stage of polio eradication. The article presents the new National Immunisation Schedule.

Safety and immunogenicity of inactivated poliovirus vaccine made from Sabin strains: A phase II, randomized, dose-finding trial

BackgroundIn order to completely eradicate polio caused by wild poliovirus infection as well as vaccine-associated paralytic polio (VAPP), Sabin inactivated poliovirus vaccine (sIPV) should be developed to meet the requirements for biosafety and affordable strategy in the developing countries. MethodA randomized, double-blinded clinical trial was conducted to compare the immunogenicity and safety among infants aged 2 months (60–90 days) receiving five different vaccination regimens: the test groups (A, B, and C) received three doses of sIPV with high, medium, and low D antigen content, respectively, on the month 0, 1, 2 schedule; two control groups (D and E) received three doses of conventional IPV (cIPV) or sIPV (CAMS), respectively, on the same schedule as that of test groups. Serum samples were collected immediately before the 1st dose and 30 days after the 3rd dose vaccination to assess the immunogenicity. Adverse events occurring within 30 days after each dose were collected to assess the safety. ResultsAfter three doses, seroconversion rates in groups A–E were 100%, 98.2%, 100%, 100%, and 100%, respectively, for type 1; 99.1%, 100%, 98.1%, 100%, and 97.1%, respectively, for type 2; and 100%, 100%, 100%, 100%, and 99.0%, respectively, for type 3. The seropositive rates (≥1:8) of groups A–E for all types were nearly 100%. The GMTs in the target dose group (group B) were 4635, 342, and 2218 for type 1–3, respectively. The most common injection-site and systemic adverse reactions were swelling and fever respectively. The swelling (4.2%, P = 0.0075) and fever (58.3%, P = 0.0188) frequency of group A were statistically significantly higher than any other groups. ConclusionThe test sIPV generally demonstrated good safety and immunogenicity. The medium-D antigen dose would be a preferred choice for the further phase III clinical trial in consideration of its high immunogenicity for all serotypes and the satisfying tolerance.Clinical Trials Registration. NCT02985320.

MORBIDITY OF THE POPULATION OF ARKHANGELSK REGION WITH INFECTIONS, MANAGED BY MEANS OF SPECIAL PREVENTION

Aim. To reveal the peculiarities of the incidence of the population of the Arkhangelsk region by infections controlled by means of specific prevention. Methods. A post-hoc epidemiological analysis of infection morbidity indices of the Arkhangelsk Region population, controlled by specific preventive measures (diphtheria, measles, rubella, poliomyelitis, tick-borne viral encephalitic - TBVE) has been carried out in the paper. Records and reports for the period 2011-2015 were used as data for a look back study. Results. Diphtheria morbidity on the territory of the Arkhangelsk region has kept the «zero» level during the last years. Measles morbidity in the period from 2007 to 2015 was registered in 2013 (10 cases) and in 2014 (1 case). Rubella morbidity in the period 2011-2015 was registered in 2013 году (5 cases). No cases of vaccine-associated paralytic polio were registered in the region in the period from 2006 to 2015. Infections vaccination coverage, controlled by specific preventive measures corresponds to regulated levels. The paper also presents the analysis and assessment of TBE morbidity indices, population immunization against TBVE and study results of the immunity stress to this infection in the Arkhangelsk Region. Conclusions. The results of serological examinations of children, adolescents, adults, when compared with the reference indicators, testify to sufficient specific protection, correspond to official information on vaccine coverage, and confirm the effectiveness of specific prophylaxis against diphtheria, poliomyelitis, measles and rubella. It is advisable to include immunization against TBVE in the regional calendar of preventive vaccinations.

Evaluating cessation of the type 2 oral polio vaccine by modeling pre- and post-cessation detection rates.

The globally synchronized removal of the attenuated Sabin type 2 strain from the oral polio vaccine (OPV) in April 2016 marked a major change in polio vaccination policy. This change will provide a significant reduction in the burden of vaccine-associated paralytic polio (VAPP), but may increase the risk of circulating vaccine-derived poliovirus (cVDPV2) outbreaks during the transition period. This risk can be monitored by tracking the disappearance of Sabin-like type 2 (SL2) using data from the polio surveillance system. We studied SL2 prevalence in 17 countries in Africa and Asia, from 2010 to 2016 using acute flaccid paralysis surveillance data. We modeled the peak and decay of SL2 prevalence following mass vaccination events using a beta-binomial model for the detection rate, and a Ricker function for the temporal dependence. We found type 2 circulated the longest of all serotypes after a vaccination campaign, but that SL2 prevalence returned to baseline levels in approximately 50days. Post-cessation model predictions identified 19 anomalous SL2 detections outside of model predictions in Afghanistan, India, Nigeria, Pakistan, and western Africa. Our models established benchmarks for the duration of SL2 detection after OPV2 cessation. As predicted, SL2 detection rates have plummeted, except in Nigeria where OPV2 use continued for some time in response to recent cVDPV2 detections. However, the anomalous SL2 detections suggest specific areas that merit enhanced monitoring for signs of cVDPV2 outbreaks.

Introduction of Inactivated Poliovirus Vaccine and Trivalent Oral Polio Vaccine/Bivalent Oral Polio Vaccine Switch in the African Region.

The Polio Eradication and Endgame Strategic plan outlines the phased removal of oral polio vaccines (OPVs), starting with type 2 poliovirus–containing vaccine and introduction of inactivated polio vaccine in routine immunization to mitigate against risk of vaccine-associated paralytic polio and circulating vaccine-derived poliovirus. The objective includes strengthening routine immunization as the primary pillar to sustaining high population immunity. After 2 years without reporting any wild poliovirus (July 2014–2016), the region undertook the synchronized switch from trivalent OPV (tOPV) to bivalent OPV (bOPV) as recommended by the Strategic Advisory Group of Experts on Immunization. Consequently the 47 countries of the World Health Organization (WHO) African Region switched from the use of tOPV to bOPV within the stipulated period of April 2016. Planning started early, routine immunization was strengthened, and technical and financial support was provided for vaccine registration, procurement, destruction, logistics, and management across countries by WHO in collaboration with the United Nations Children’s Fund (UNICEF) and partners. National commitment and ownership, as well as strong coordination and collaboration between UNICEF and WHO and with partners, ensured success of this major, historic public health undertaking.

Introduction of inactivated poliovirus vaccine leading into the polio eradication endgame strategic plan; Hangzhou, China, 2010–2014

BackgroundChina’s Expanded Program on Immunization (EPI) has provided 4 doses of oral poliovirus vaccine (OPV) since the 1970s. Inactivated poliovirus vaccine (IPV) became available in 2010 in Hangzhou as a private-sector, parent-chosen alternative to OPV. In 2015, WHO recommended that countries with all-OPV vaccination schedules introduce at least one dose of IPV, to mitigate risk associated with the withdrawal of type 2 OPV. We analyzed polio vaccine coverage and utilization in Hangzhou to determine patterns of IPV use and the occurrence of vaccine-associated paralytic polio (VAPP) in the various patterns identified. MethodsChildren born between 2010 and 2014 and registered in Hangzhou’s Immunization Information System (HZIIS) were included. VAPP cases were detected through the acute flaccid paralysis surveillance system. We used descriptive epidemiological methods to determine IPV and OPV usage patterns and VAPP occurrence. ResultsHZIIS data from 566,894 children were analyzed. Coverage levels of polio vaccine were greater than 92% for each birth cohort. Percentages of children using OPV-only, IPV-only, and IPV/OPV sequential schedules were 70.57%, 27.01% and 2.41%, respectively. IPV-only schedule utilization increased by birth cohort regardless of geographical area or whether the child was locally-born. The highest use of an all-IPV schedule (79.85%) was among urban, locally-born children in the 2014 birth cohort. Five VAPP cases were identified during the study years; all cases occurred following the first polio vaccine dose, which was always OPV for the cases. Type 2 vaccine virus was isolated from 2 VAPP cases, and type 2 and type 3 vaccine virus was isolated from one VAPP case. The incidence of VAPP in the 2010–2014 birth cohorts was 3.76 per 1million doses of OPV. ConclusionChildren in Hangzhou had high polio vaccination coverage. IPV-only schedule use increased by year, and was highest in urban areas among locally-born children. All cases of VAPP were associated with the first dose of OPV.

Preventing Polio Post-eradication: Revertant Proportion Patterns of OPV Serotypes

Background As wild poliovirus is eradicated and countries switch from oral polio vaccine (OPV) to inactivated polio vaccine (IPV), preventing circulating vaccine-derived poliovirus is a top priority. However, the stability of Sabin vaccine serotypes remains a concern in undervaccinated communities. We sought to measure the canonical point mutation rates associated with OPV serotype neuroreversion and vaccine-associated paralytic polio (VAPP) as possible markers of serotype fitness. Mexico provides a natural environment to study these patterns as it provides routine IPV immunization and bi-annual OPV campaigns.Methods We enrolled 450 households with children eligible for OPV before the February 2015 national immunization week from three communities near Orizaba, Mexico. In each community, a different proportion of eligible children received OPV (10, 30, and 70%). Transmission was measured by PCR detection of OPV in samples collected serially from vaccinated children, their households, and other families in the community. Positive samples were reanalyzed to quantify revertant proportion (RP), the percent of OPV VAPP mutants found in positive samples.Results15,109 samples were collected and analyzed from 1,828 participants. 554 (3.7%) were OPV positive, and 194 have been reanalyzed for RP to date.The majority of OPV 1 positive samples showed <25% revertance as late as 71 days post-vaccination (Figure 1). By contrast, OPV 2 and OPV 3 positive samples quickly revert to VAPP OPV. The majority of OPV 2 positive samples were >75% revertant by Day 7 (Figure 2), while the majority of OPV 3 positive samples were >75% revertant by Day 4 (Figure 3).Conclusion OPV 1 appears to be more stable than OPV 2 and OPV 3, remaining <25% revertant 71 days post-vaccination. OPV 2 reverts quickly, with most samples reverting to VAPP by Day 7, while OPV 3 reverts the fastest, with most samples reverting to VAPP by Day 4. Understanding the stability of OPV and VAPP mutants may shed some light on the ability of OPV serotypes to persist in community circulation. Analyses regarding potential covariates for VAPP and RP are currently underway.Figure 1:OPV 1 RP over time.Figure 2:OPV 2 RP over time.Figure 3:OPV 3 RP over time.Disclosures All authors: No reported disclosures.

Differential preference for pertussis and poliomyelitis vaccines in urban versus rural parents in Guatemala.

The Global Polio Eradication Initiative is close to achieving its goal. Oral polio vaccines (OPVs) rarely cause vaccine-associated paralytic polio (VAPP) or circulating vaccine-derived poliovirus outbreaks. To diminish these risks, inactivated polio vaccine (IPV) was reintroduced in most industrialized countries in the 1990s. Another vaccine, acellular pertussis (aP), was also incorporated to circumvent the reactogenicity of whole-cell pertussis (wP); the latter is currently used in most developing countries (DCs). However, recent outbreaks of pertussis in countries using aP attributed to waning immunity but seen less with wP mean that most DCs will likely retain wP as the preferred vaccine. How parents regard these changes in DCs is unknown. We investigated parental preferences for polio and pertussis vaccines in Guatemala among different geographical populations.