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1.
Cell Host Microbe ; 29(1): 3-5, 2021 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-33444554

RESUMEN

Troubled by an unstable world beset by new and emerging viruses? Virus evolution is here to help. Through detailed studies of poliovirus vaccine reversion to virulence, Valesano and colleagues remind us that some things in life can, indeed, be counted on.


Asunto(s)
Poliomielitis , Poliovirus , Humanos , Mutación , Poliomielitis/prevención & control , Poliovirus/genética , Vacuna Antipolio Oral , Vacunación
2.
Brasília, D.F.; OPAS; 2021-01-19. (OPAS-W/BRA/FPL/20-176).
No convencional en Portugués | PAHO-IRIS | ID: phr2-53204

RESUMEN

A Estratégia de Erradicação da Poliomielite 2019-2023 posicionou o atual período estratégico de cinco anos da GPEI em relação à dupla emergência enfrentada pelo esforço de erradicação da poliomielite: que o programa deve interromper o WPV1 e parar a transmissão do cVDPV. Em consideração às implicações potenciais de longo prazo para surtos de cVDPV, a Estratégia de Erradicação sinalizou a importância de um plano de contingência para mitigar o risco de cVDPVs por meio de intervenções de curto prazo, protocolos de emergência e mudanças de políticas. A Estratégia para a Resposta ao Poliovírus Derivado da Vacina Circulante Tipo 2 2020–2021 é oferecida como um adendo que atende a essa necessidade de um plano de contingência. Foi desenvolvida por um grupo de trabalho e em consulta com especialistas da parceria GPEI: a Organização Mundial da Saúde (OMS), o Fundo das Nações Unidas para a Infância (UNICEF), o Rotary International, os Centros para Controle e Prevenção de Doenças dos EUA (CDC), a Fundação Bill & Melinda Gates (FBMG) e a Gavi, a Aliança das Vacinas. O Anexo A fornece uma visão geral sobre a supervisão e gestão desse adendo para responder aos surtos de cVDPV2. A estratégia será regularmente revisada e atualizada conforme necessário para atender a necessidades contínuas. Essa estratégia de 18 meses (janeiro de 2020 a junho de 2021) apresenta uma série de medidas de mitigação de risco para interromper a propagação do cVDPV2. Ela prioriza o uso de ativos do programa e utiliza uma nova vacina para melhorar os resultados da resposta ao surto. Prevê-se que essa nova vacina, chamada de nova VOP2, forneça imunidade intestinal semelhante à da Sabin VOP2, embora seja substancialmente mais estável geneticamente e, portanto, resistente à reversão, reduzindo os riscos associados à resposta cVDPV2. Com duas candidatas na linha de pesquisa e desenvolvimento, a nova VOP2 deve estar disponível em meados de 2020 por meio da Lista de Uso de Emergência da OMS (LUE)3. Informações sobre o licenciamento e a produção da nova VOP2 são fornecidas no Anexo B.


Asunto(s)
Pandemias , Poliomielitis , Inmunización , Erradicación de la Enfermedad , Poliovirus , Vacunas contra Poliovirus
3.
Artículo en Inglés | MEDLINE | ID: mdl-33499422

RESUMEN

The COVID-19 pandemic has had an impact on health service delivery, including immunization programs, and this review assesses the impact on vaccine coverage across the globe and identifies the potential underlying factors. A systematic search strategy was employed on PubMed, Embase, MedRxiv, BioRxiv, and WHO COVID-19 databases from December 2019 till 15 September 2020. Two review authors independently assessed studies for inclusion, assessed quality, and extracted the data (PROSPERO registration #CRD42020182363). A total of 17 observational studies were included. The findings suggest that there was a reduction in the vaccination coverage and decline in total number of vaccines administered, which led to children missing out on their vaccine doses. An approximately fourfold increase was also observed in polio cases in polio endemic countries. Factors contributing to low vaccine coverage included fear of being exposed to the virus at health care facilities, restriction on city-wide movements, shortage of workers, and diversion of resources from child health to address the pandemic. As the world re-strategizes for the post-2020 era, we should not let a crisis go to waste as they provide an opportunity to establish guidelines and allocate resources for future instances. High-quality supplementary immunization activities and catch-up programs need to be established to address gaps during the pandemic era.


Asunto(s)
Programas de Inmunización/tendencias , Pandemias , Vacunación/estadística & datos numéricos , Niño , Humanos , Estudios Observacionales como Asunto , Poliomielitis/epidemiología
4.
MMWR Morb Mortal Wkly Rep ; 69(5152): 1648-1652, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33382673

RESUMEN

On January 30, 2020, the World Health Organization (WHO) declared coronavirus disease 2019 (COVID-19) a Public Health Emergency of International Concern (1). On March 24, 2020, the Global Polio Eradication Initiative (GPEI) suspended all polio supplementary immunization activities and recommended the continuation of polio surveillance (2). In April 2020, GPEI shared revised polio surveillance guidelines in the context of the COVID-19 pandemic, which focused on reducing the risk for transmission of SARS-CoV-2, the virus that causes COVID-19, to health care workers and communities by modifying activities that required person-to-person contact, improving hand hygiene and personal protective equipment use practices, and overcoming challenges related to movement restrictions, while continuing essential polio surveillance functions (3). GPEI assessed the impact of the COVID-19 pandemic on polio surveillance by comparing data from January to September 2019 to the same period in 2020. Globally, the number of acute flaccid paralysis (AFP) cases reported declined 33% and the mean number of days between the second stool collected and receipt by the laboratory increased by 70%. Continued analysis of AFP case reporting and stool collection is critical to ensure timely detection and response to interruptions of polio surveillance.


Asunto(s)
Salud Global , Poliomielitis/epidemiología , Vigilancia de la Población , Técnicas de Laboratorio Clínico/estadística & datos numéricos , Erradicación de la Enfermedad , Heces/virología , Humanos , Poliomielitis/prevención & control , Poliovirus/aislamiento & purificación , Vacunas contra Poliovirus/administración & dosificación
5.
Artículo en Inglés | MEDLINE | ID: mdl-33333947

RESUMEN

A combination of high infant immunization coverage and surveillance of acute flaccid paralysis (AFP) cases, plays a critical role in polio eradication. This study aimed to estimate the incidence of AFP, to evaluate the completeness of AFP ascertainment during the years, age groups and gender, and to define the main associated diagnosis among children aged under 15 in the Marches region of Italy. Analysis was performed on data from the active AFP surveillance system and the hospital discharge records in the 2006-2014 period. The two-source capture-recapture method was applied. After cross-validation, 30 AFP compatible conditions as defined by the WHO were identified, with an incidence estimate of 1.91 cases of AFP per 100,000 children under 15 years (95% CI = 1.4-2.6/100,000). Guillain-Barrè syndrome was the most common diagnosis. A significant difference (p < 0.05) has been registered in the estimated probability of case ascertainment in females. The reasons for the lower reporting of cases in females are unknown. Specific research and the implementation of a more sensitive surveillance system are essential in verifying potential inequalities and to succeed in the polio eradication initiative.


Asunto(s)
Enfermedades Virales del Sistema Nervioso Central , Mielitis , Enfermedades Neuromusculares , Parálisis , Adolescente , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Italia/epidemiología , Masculino , Parálisis/epidemiología , Poliomielitis/epidemiología , Vigilancia de la Población
7.
Med Sci (Paris) ; 36(11): 1034-1037, 2020 Nov.
Artículo en Francés | MEDLINE | ID: mdl-33151866

RESUMEN

Coronavirus disease (COVID)-19 is an emerging pandemic infection whose significant ability to spread in a naïve population is well established. The first response of states to the COVID-19 outbreak was to impose lock-down and social barrier measures, such as wearing a surgical mask or social distancing. One of the consequences of this pandemic in terms of public health was the suspension or slowdown of infant vaccination campaigns, in almost all countries. The indirect effects of COVID-19 may therefore weigh on mortality from measles and polio in developing countries. In this pandemic chaos, the only hope lies in the rapid development of an effective vaccine against severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). However, acceptance of this vaccine has not yet been won, as beyond the many unknowns that will inevitably weigh around such rapid development, skepticism among vaccine hesitants is growing.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Programas de Inmunización/estadística & datos numéricos , Pandemias , Neumonía Viral/epidemiología , Salud Pública/estadística & datos numéricos , Vacunación/estadística & datos numéricos , Betacoronavirus/fisiología , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/prevención & control , Brotes de Enfermedades/prevención & control , Accesibilidad a los Servicios de Salud/organización & administración , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Humanos , Programas de Inmunización/organización & administración , Programas de Inmunización/normas , Programas de Inmunización/tendencias , Sarampión/epidemiología , Sarampión/prevención & control , Pandemias/prevención & control , Participación del Paciente/estadística & datos numéricos , Participación del Paciente/tendencias , Neumonía Viral/inmunología , Neumonía Viral/prevención & control , Poliomielitis/epidemiología , Poliomielitis/prevención & control , Salud Pública/normas , Salud Pública/tendencias , Cobertura de Vacunación/organización & administración , Cobertura de Vacunación/estadística & datos numéricos , Vacunas Virales/uso terapéutico
8.
MMWR Morb Mortal Wkly Rep ; 69(46): 1748-1752, 2020 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-33211676

RESUMEN

Pakistan and Afghanistan are the only countries where wild poliovirus type 1 (WPV1) is endemic (1,2). In 2019, Pakistan reported 147 WPV1 cases, approximately 12 times the number reported in 2018. As of September 15, 72 cases had been reported in 2020. Since 2019, WPV1 transmission has also spread from Pakistan's core poliovirus reservoirs (Karachi, Peshawar, and Quetta block) to southern districts of Khyber Pakhtunkhwa (KP), Punjab, and Sindh provinces. Further, an outbreak of circulating vaccine-derived poliovirus type 2 (cVDPV2), first detected in July 2019, has caused 22 paralytic cases in 2019 and 59 as of September 15, 2020, throughout the country. The coronavirus disease 2019 (COVID-19) pandemic has substantially reduced delivery of polio vaccines through essential immunization (formerly routine immunization) and prevented implementation of polio supplementary immunization activities (SIAs)* during March-July 2020. This report describes Pakistan's progress in polio eradication during January 2019-September 2020 and updates previous reports (1,3,4). The Pakistan polio program has reinitiated SIAs and will need large, intensive, high-quality campaigns with strategic use of available oral poliovirus vaccines (OPVs)† to control the surge and widespread transmission of WPV1 and cVDPV2.


Asunto(s)
Erradicación de la Enfermedad , Poliomielitis/prevención & control , Vigilancia de la Población , Adolescente , Niño , Preescolar , Humanos , Esquemas de Inmunización , Lactante , Pakistán/epidemiología , Poliomielitis/epidemiología , Vacunas contra Poliovirus/administración & dosificación , Vacunación/estadística & datos numéricos
11.
Glob Health Sci Pract ; 8(3): 396-412, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-33008854

RESUMEN

This article assesses the CORE Group Polio Project (CGPP) experience over a 20-year period in 5 countries. It examines how a program designed to provide social mobilization to eradicate one disease, and which did so effectively, functioned within the general framework of community health workers (CHWs). Vertical health programs often have limited impact on broader community health. CGPP has a 20-year history of social mobilization and effective program interventions. This history provided an opportunity to assess how CGPP community mobilizers (CMs) functioned in polio and maternal and child health. The Updated Program Functionality Matrix for Optimizing Community Health Programs tool of the CHW Assessment and Improvement Matrix (AIM) was used to examine CGPP CM roles across different contexts. The analysis determined that CGPP CMs met the basic level of functioning (level 3) for 6 of the 10 components of the AIM tool. This cross-country descriptive analysis of the CGPP demonstrates the importance of embracing the full range of CHW AIM components, even in a vertical program. Use of data, community involvement, local adaptation, and linkage with the health system are especially critical for success. This general lesson could be applied to other community mobilization and disease/epidemic control initiatives, especially as we face the issues of the COVID-19 pandemic.


Asunto(s)
Agentes Comunitarios de Salud , Erradicación de la Enfermedad/métodos , Poliomielitis/prevención & control , Evaluación de Programas y Proyectos de Salud/métodos , Servicios de Salud Rural , África , Asia , Humanos , Población Rural
12.
MMWR Morb Mortal Wkly Rep ; 69(40): 1464-1468, 2020 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-33031360

RESUMEN

Wild poliovirus type 1 (WPV1) transmission is ongoing only in Afghanistan and Pakistan (1). Following a decline in case numbers during 2013-2016, the number of cases in Afghanistan has increased each year during 2017-2020. This report describes polio eradication activities and progress toward polio eradication in Afghanistan during January 2019-July 2020 and updates previous reports (2,3). Since April 2018, insurgent groups have imposed bans on house-to-house vaccination. In September 2019, vaccination campaigns in areas under insurgency control were restarted only at health facilities. In addition, during March-June 2020, all campaigns were paused because of the coronavirus disease 2019 (COVID-19) pandemic. The number of WPV1 cases reported in Afghanistan increased from 21 in 2018 to 29 in 2019. During January-July 2020, 41 WPV1 cases were reported as of August 29, 2020 (compared with 15 during January-July 2019); in addition, 69 cases of circulating vaccine-derived poliovirus type 2 (cVDPV2), and one case of ambiguous vaccine-derived poliovirus type 2 (aVDPV2) (isolates with no evidence of person-to-person transmission or from persons with no known immunodeficiency) were detected. Dialogue with insurgency leaders through nongovernmental and international organizations is ongoing in an effort to recommence house-to-house campaigns, which are essential to stopping WPV1 transmission in Afghanistan. To increase community demand for polio vaccination, additional community health needs should be addressed, and polio vaccination should be integrated with humanitarian services.


Asunto(s)
Erradicación de la Enfermedad , Poliomielitis/prevención & control , Vigilancia de la Población , Adolescente , Afganistán/epidemiología , Niño , Preescolar , Humanos , Programas de Inmunización , Esquemas de Inmunización , Lactante , Poliomielitis/epidemiología , Poliovirus/aislamiento & purificación , Vacuna Antipolio Oral/administración & dosificación , Vacunación/estadística & datos numéricos
15.
BMC Infect Dis ; 20(1): 641, 2020 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-32867698

RESUMEN

BACKGROUND: Maternal poliovirus antibodies could provide passive immunity to the newborns from poliovirus infection during their first few months of life, but they may impair the immune responses of infants to the poliovirus vaccine as well. In our study, we pooled the data from three clinical trials of the inactivated poliovirus vaccine (IPV) based on Sabin strains to investigate the effect of maternal poliovirus antibodies on the immune responses of infants to poliovirus vaccines. METHODS: There were five groups in the pooled analysis, including low-dose Sabin IPV, medium-dose Sabin IPV, high-dose Sabin IPV, control Sabin IPV, and control Salk IPV groups. We reclassified the infants in different groups according to their maternal poliovirus antibodies by two methods, the first one included maternal antibody negative (< 1:8) and maternal antibody positive (≥1:8), and the second one included maternal antibody titer < 1:8, 1:8 ~ < 1:32 and ≥ 1:32. Then, we compared the geometric mean titers (GMTs), geometric mean antibody fold increases (GMIs) and seroconversion rates of poliovirus type-specific neutralizing antibodies after vaccination among participants with different maternal poliovirus antibody levels. RESULTS: The GMTs and GMIs of three types of poliovirus antibodies after vaccination in maternal antibody negative participants were significantly higher than those in maternal antibody positive participants. The seroconversion rates of type II and type III poliovirus antibodies in maternal antibody positive participants were significantly lower than those in maternal antibody negative participants. Among participants with maternal antibody titer < 1:8, 1:8 ~ < 1:32 and ≥ 1:32, the GMTs and GMIs of three types of poliovirus antibodies after vaccination showed a tendency to decline with the increasing of maternal antibody levels. The seroconversion rates of three types of poliovirus antibodies in participants with maternal antibody titer ≥1:32 were significantly lower than those in participants with maternal antibody titer < 1:8 and 1:8 ~ < 1:32. CONCLUSIONS: Maternal poliovirus antibodies interfered with the immune responses of infants to poliovirus vaccines, and a high level of maternal antibodies exhibited a greater dampening effect. TRIAL REGISTRATION: ClinicalTrials.gov NCT04264598 February 11, 2020; ClinicalTrials.gov NCT04264546 February 11, 2020; ClinicalTrials.gov NCT03902054 April 3, 2019. Retrospectively registered.


Asunto(s)
Anticuerpos Antivirales/inmunología , Inmunidad Materno-Adquirida/inmunología , Inmunogenicidad Vacunal , Poliomielitis/prevención & control , Vacuna Antipolio de Virus Inactivados/uso terapéutico , Poliovirus/inmunología , Vacunación/métodos , Anticuerpos Neutralizantes/inmunología , China , Femenino , Humanos , Lactante , Masculino , Poliomielitis/virología , Vacuna Antipolio de Virus Inactivados/efectos adversos , Seroconversión
17.
MMWR Morb Mortal Wkly Rep ; 69(37): 1330-1333, 2020 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-32941411

RESUMEN

Since 1988, when World Health Organization (WHO) Member States and partners launched the Global Polio Eradication Initiative, the number of wild poliovirus (WPV) cases has declined from 350,000 in 125 countries to 176 in only two countries in 2019 (1). The Global Commission for the Certification of Poliomyelitis Eradication (GCC) declared two of the three WPV types, type 2 (WPV2) and type 3 (WPV3), eradicated globally in 2015 and 2019, respectively (1). Wild poliovirus type 1 (WPV1) remains endemic in Afghanistan and Pakistan (1). Containment under strict biorisk management measures is vital to prevent reintroduction of eradicated polioviruses into communities from poliovirus facilities. In 2015, Member States committed to contain type 2 polioviruses (PV2) in poliovirus-essential facilities (PEFs) certified in accordance with a global standard (2). Member states agreed to report national PV2 inventories annually, destroy unneeded PV2 materials, and, if retaining PV2 materials, establish national authorities for containment (NACs) and a PEF auditing process. Since declaration of WPV3 eradication in October 2019, these activities are also required with WPV3 materials. Despite challenges faced during 2019-2020, including the coronavirus disease 2019 (COVID-19) pandemic, the global poliovirus containment program continues to work toward important milestones. To maintain progress, all WHO Member States are urged to adhere to the agreed containment resolutions, including officially establishing legally empowered NACs and submission of PEF Certificates of Participation.


Asunto(s)
Erradicación de la Enfermedad , Salud Global/estadística & datos numéricos , Poliomielitis/prevención & control , Humanos , Poliomielitis/epidemiología , Vacuna Antipolio Oral/administración & dosificación
18.
Lancet Glob Health ; 8(10): e1345-e1351, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32916086

RESUMEN

On Aug 25 2020, the Africa Regional Commission for the Certification of Poliomyelitis Eradication declared that the WHO African region had interrupted transmission of all indigenous wild polioviruses. This declaration marks the African region as the fifth of the six WHO regions to celebrate this extraordinary achievement. Following the Yaoundé Declaration on Polio Eradication in Africa by heads of state and governments in 1996, Nelson Mandela launched the Kick Polio out of Africa campaign. In this Health Policy paper, we describe the long and turbulent journey to the certification of the interruption of wild poliovirus transmission, focusing on 2016-20, lessons learned, and the strategies and analyses that convinced the Regional Commission that the African region is free of wild polioviruses. This certification of the WHO African region shows the feasibility of polio eradication in countries with chronic insecurity, inaccessible and hard-to-reach populations, and weak health systems. Challenges have been daunting and the sacrifices enormous-dozens of health workers and volunteers have lost their lives in the pursuit of a polio-free Africa.


Asunto(s)
Erradicación de la Enfermedad/métodos , Salud Global , Poliomielitis/prevención & control , Organización Mundial de la Salud , África , Humanos , Poliomielitis/transmisión
19.
PLoS Pathog ; 16(9): e1008920, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32997730

RESUMEN

The virions of enteroviruses such as poliovirus undergo a global conformational change after binding to the cellular receptor, characterized by a 4% expansion, and by the opening of holes at the two and quasi-three-fold symmetry axes of the capsid. The resultant particle is called a 135S particle or A-particle and is thought to be on the pathway to a productive infection. Previously published studies have concluded that the membrane-interactive peptides, namely VP4 and the N-terminus of VP1, are irreversibly externalized in the 135S particle. However, using established protocols to produce the 135S particle, and single particle cryo-electron microscopy methods, we have identified at least two unique states that we call the early and late 135S particle. Surprisingly, only in the "late" 135S particles have detectable levels of the VP1 N-terminus been trapped outside the capsid. Moreover, we observe a distinct density inside the capsid that can be accounted for by VP4 that remains associated with the genome. Taken together our results conclusively demonstrate that the 135S particle is not a unique conformation, but rather a family of conformations that could exist simultaneously.


Asunto(s)
Cápside/ultraestructura , Poliomielitis/metabolismo , ARN Viral/ultraestructura , Virión/ultraestructura , Cápside/metabolismo , Proteínas de la Cápside/metabolismo , Microscopía por Crioelectrón , Humanos , Modelos Moleculares , ARN Viral/metabolismo , Receptores Virales/metabolismo , Virión/metabolismo , Internalización del Virus
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