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Biologicals : Journal of the... Sep 2020Effective decontamination procedures are critical to the successful manufacture and control of poliovirus vaccines to minimize the risk to personnel and the environment....
Effective decontamination procedures are critical to the successful manufacture and control of poliovirus vaccines to minimize the risk to personnel and the environment. Polio viruses have been reported to be more resistant to disinfectants than many other viruses. We assessed the efficacy of sodium hypochlorite-containing disinfectants for decontamination for three poliovirus serotypes to implement decontamination procedures that are fully compliant with the WHO GAP III and Health authorities' requirements. A 10.4 log reduction was observed with a 0.63% sodium hypochlorite solution in a suspension with high protein and high poliovirus concentrations diluted 10-fold compared with a 6 log reduction in an undiluted sample. Treatment efficacy increased with sodium hypochlorite content and decreased with sample protein content. The surface tests showed that two 1-min treatments, 5-min apart, with a 0.63% Chl sodium hypochlorite solution effectively reduced the concentration of all poliovirus serotypes by 10 log, irrespective of the protein and virus concentration in the sample. Sodium hypochlorite solutions lower than 0.52% were less effective for complete inactivation of poliovirus. In conclusion, we demonstrated that a high level of virus reduction (>10 log) can be achieved with sodium hypochlorite solutions with poliovirus in suspension and dried on surfaces.
Topics: Decontamination; Disinfectants; Humans; Infection Control; Poliomyelitis; Poliovirus; Reproducibility of Results; Serogroup; Sodium Hypochlorite; Solutions; Species Specificity; Viral Load
PubMed: 32807609
DOI: 10.1016/j.biologicals.2020.07.007 -
Vaccine Apr 2023In addition to affecting individual health the COVID-19 pandemic has disrupted efforts to deliver essential health services around the world. In this article we present... (Review)
Review
In addition to affecting individual health the COVID-19 pandemic has disrupted efforts to deliver essential health services around the world. In this article we present an overview of the immediate programmatic and epidemiologic impact of the pandemic on polio eradication as well as the adaptive strategic and operational measures taken by the Global Polio Eradication Initiative (GPEI) from March through September 2020. Shortly after the World Health Organization (WHO) declared a global pandemic on 11 March 2020, the GPEI initially redirected the programme's assets to tackle COVID-19 and suspended house-to-house supplementary immunization activities (SIAs) while also striving to continue essential poliovirus surveillance functions. From March to May 2020, 28 countries suspended a total of 62 polio vaccine SIAs. In spite of efforts to continue poliovirus surveillance, global acute flaccid paralysis (AFP) cases reported from January-July 2020 declined by 34% compared with the same period in 2019 along with decreases in the mean number of environment samples collected per active site in the critical areas of the African and Eastern Mediterranean regions. The GPEI recommended countries should resume planning and implementation of SIAs starting in July 2020 and released guidelines to ensure these could be done safely for front line workers and communities. By the end of September 2020, a total of 14 countries had implemented circulating vaccine-derived poliovirus type 2 (cVDPV2) outbreak response vaccination campaigns and Afghanistan and Pakistan restarted SIAs to stop ongoing wild poliovirus type 1 (WPV1) transmission. The longer-term impacts of disruptions to eradication efforts remain to be determined, especially in terms of the effect on poliovirus epidemiology. Adapting to the pandemic situation has imposed new considerations on program implementation and demonstrated not only GPEI's contribution to global health security, but also identified potential opportunities for coordinated approaches across immunization and health services.
Topics: Humans; Pandemics; Disease Eradication; Population Surveillance; COVID-19; Poliovirus; Poliomyelitis; Poliovirus Vaccine, Oral; Vaccination; Immunization Programs
PubMed: 34756614
DOI: 10.1016/j.vaccine.2021.10.028 -
Journal of Medical Virology Mar 2020Poliovirus (PV) is a member of the species Enterovirus C (EV-C), which may cause irreversible paralysis and death. So, for the purpose of analyzing the evolution of PV2...
Poliovirus (PV) is a member of the species Enterovirus C (EV-C), which may cause irreversible paralysis and death. So, for the purpose of analyzing the evolution of PV2 to help in eradicating PVs globally, a recombination analysis was performed to verify all viral genomes of EV-C, and we found 13 putative recombination events that produced PV1, 14 recombination events that can give rise to PV2, and 9 events that can lead to PV3. By analyzing our findings, we found that PV2 was involved in 25 of 36 PV recombination events, whereas coxsackievirus A (CVA) strains were involved in 12 of 36 PV recombination events, indicating that PV2 and CVAs play major roles in the natural recombination of PV. In addition, we found 11 of 36 breakpoint positions located in 2A region, which is the most active region of the recombination events.
Topics: Enterovirus A, Human; Genome, Viral; Phylogeny; Poliovirus; Recombination, Genetic; Serogroup
PubMed: 31674680
DOI: 10.1002/jmv.25620 -
BMJ (Clinical Research Ed.) Oct 2022
Topics: Disease Eradication; Global Health; Humans; Immunization Programs; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Inactivated; Poliovirus Vaccine, Oral
PubMed: 36195323
DOI: 10.1136/bmj.o2388 -
The Lancet. Infectious Diseases Aug 2021
Topics: Humans; Poliomyelitis; Poliovirus
PubMed: 33939959
DOI: 10.1016/S1473-3099(20)30774-X -
Medecine Tropicale Et Sante... Jun 2021In 2019, the Central African Republic identified foci of circulating vaccine-derived poliovirus 2 (PVDV2c). The objective of this work is to describe the vaccination...
OBJECTIVE
In 2019, the Central African Republic identified foci of circulating vaccine-derived poliovirus 2 (PVDV2c). The objective of this work is to describe the vaccination status of children paralyzed by PVDV2c and their contacts and to assess the circulation of this strain in these contacts.
PATIENTS AND METHOD
The study population of this retrospective survey consists of children with acute flaccid paralysis (AFP) and their contacts. We included paralyzed children whose sequencing results showed the presence of PVDV2c.
RESULTS
A total of 21 children paralyzed by PVDVc and 64 contacts were enrolled in the survey. Fourteen out of 21 children who are paralyzed (66%) received at least one dose of bivalent oral polio vaccine (OPV) compared to 36 out of 64 contacts (57%, non-significant difference). Of the vaccinated patients, 7 had received less than three doses. For the injectable polio vaccine (IPV), vaccination coverage for both patients and contacts was 33%.The proportion of children who received both doses of OPV and IPV was 33% among patients and 25% in contacts. Contacts with VDPV2 were vaccinated with OPV and IPV, respectively 55 and 27%. VDPV2 and Sabin 2 were also found in contact stools, 34% and 9% respectively.
CONCLUSION
The absence or inadequacy of IPV vaccination has a serious impact on children by the occurrence of virus derived from the vaccine responsible for life-old paralysis. Protecting children from poliomyelitis requires a combination of a good cold chain, multiple doses and adherence to the vaccine schedule.
Topics: Central African Republic; Child; Humans; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Oral; Poliovirus Vaccines; Retrospective Studies
PubMed: 35586583
DOI: 10.48327/mtsibulletin.2021.114 -
MMWR. Morbidity and Mortality Weekly... Apr 2023Since the Global Polio Eradication Initiative (GPEI) began in 1988, the number of wild poliovirus (WPV) cases has declined by >99.99%. Five of the six World Health...
Since the Global Polio Eradication Initiative (GPEI) began in 1988, the number of wild poliovirus (WPV) cases has declined by >99.99%. Five of the six World Health Organization (WHO) regions have been certified free of indigenous WPV, and WPV serotypes 2 and 3 have been declared eradicated globally (1). WPV type 1 (WPV1) remains endemic only in Afghanistan and Pakistan (2,3). Before the outbreak described in this report, WPV1 had not been detected in southeastern Africa since the 1990s, and on August 25, 2020, the WHO African Region was certified free of indigenous WPV (4). On February 16, 2022, WPV1 infection was confirmed in one child living in Malawi, with onset of paralysis on November 19, 2021. Genomic sequence analysis of the isolated poliovirus indicated that it originated in Pakistan (5). Cases were subsequently identified in Mozambique. This report summarizes progress in the outbreak response since the initial report (5). During November 2021-December 2022, nine children and adolescents with paralytic polio caused by WPV1 were identified in southeastern Africa: one in Malawi and eight in Mozambique. Malawi, Mozambique, and three neighboring countries at high risk for WPV1 importation (Tanzania, Zambia, and Zimbabwe) responded by increasing surveillance and organizing up to six rounds of national and subnational polio supplementary immunization activities (SIAs).* Although no cases of paralytic WPV1 infection have been reported in Malawi since November 2021 or in Mozambique since August 2022, undetected transmission might be ongoing because of poliovirus surveillance gaps and testing delays. Efforts to further enhance poliovirus surveillance sensitivity, improve SIA quality, and strengthen routine immunization are needed to ensure that WPV1 transmission has been interrupted within 12 months of the first case, thereby preserving the WHO African Region's WPV-free status.
Topics: Child; Adolescent; Humans; Poliovirus; Population Surveillance; Poliomyelitis; Disease Outbreaks; Malawi; Poliovirus Vaccine, Oral; Immunization Programs; Disease Eradication
PubMed: 37053125
DOI: 10.15585/mmwr.mm7215a3 -
Risk Analysis : An Official Publication... Feb 2021The Global Polio Eradication Initiative (GPEI) partners engaged modelers during the past nearly 20 years to support strategy and policy discussions and decisions, and to... (Review)
Review
The Global Polio Eradication Initiative (GPEI) partners engaged modelers during the past nearly 20 years to support strategy and policy discussions and decisions, and to provide estimates of the risks, costs, and benefits of different options for managing the polio endgame. Limited efforts to date provided insights related to the validation of the models used for GPEI strategy and policy decisions. However, modeling results only influenced decisions in some cases, with other factors carrying more weight in many key decisions. In addition, the results from multiple modeling groups do not always agree, which supports selection of some strategies and/or policies counter to the recommendations from some modelers but not others. This analysis reflects on our modeling, and summarizes our premises and recommendations, the outcomes of these recommendations, and the implications of key limitations of models with respect to polio endgame strategy. We briefly review the current state of the GPEI given epidemiological experience as of early 2020, which includes failure of the GPEI to deliver on the objectives of its 2013-2018 strategic plan despite full financial support. Looking ahead, we provide context for why the GPEI strategy of global oral poliovirus vaccine (OPV) cessation to end all cases of poliomyelitis looks infeasible given the current state of the GPEI and the failure to successfully stop all transmission of serotype 2 live polioviruses within four years of the April-May 2016 coordinated cessation of serotype 2 OPV use in routine immunization.
Topics: Basic Reproduction Number; Disease Eradication; Disease Outbreaks; Global Health; Humans; Immunization Programs; Models, Theoretical; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Inactivated; Poliovirus Vaccine, Oral; Risk; Risk Assessment; Risk Management; Vaccination
PubMed: 32339327
DOI: 10.1111/risa.13484 -
JAMA Network Open Jan 2023The Sabin-strain inactivated poliovirus vaccine (IPV) may be a tool for polio outbreak response in certain situations.
IMPORTANCE
The Sabin-strain inactivated poliovirus vaccine (IPV) may be a tool for polio outbreak response in certain situations.
OBJECTIVE
To investigate the response to a type 2 vaccine-derived poliovirus (VDPV2) outbreak.
DESIGN, SETTING, AND PARTICIPANTS
This case series was conducted in China after a VDPV2 was detected in stool specimens from a child with acute flaccid paralysis (AFP) in Sichuan Province in 2019, 3 years after the global withdrawal of live, attenuated type 2 oral poliovirus vaccine (OPV). Investigation followed National Health Commission and World Health Organization guidance and included searching hospitals for unreported AFP cases; testing stool specimens from the child, his contacts, and local children; enhanced environmental surveillance for VDPV2s in wastewater; and measuring vaccination coverage. Sabin-strain IPV campaigns were conducted in a wide geographic area.
MAIN OUTCOMES AND MEASURES
Any VDPV2 detection after completion of the supplementary immunization activities.
RESULTS
A 28-nucleotide-change VDPV2 was isolated from a young boy. Three VDPV2s were detected in healthy children; 2 were contacts of the original child, and none had paralysis. A search of 31 million hospital records found 10 unreported AFP cases; none were polio. No type 2 polioviruses were found in wastewater. Prior to the event, polio vaccine coverage was 65% among children younger than 5 years. Sabin-strain IPV campaigns reached more than 97% of targeted children, administering 1.4 million doses. No transmission source was identified. More than 1 year of enhanced poliovirus environmental and AFP surveillance detected no additional VDPVs.
CONCLUSIONS AND RELEVANCE
These findings suggest that the circulating VPDV2 outbreak in 2019 was associated with low vaccine coverage. An investigation discovered 3 infected but otherwise healthy children and no evidence of the virus in wastewater. Following Sabin-strain IPV-only campaigns expanding from county to prefecture, the poliovirus was not detected, and the outbreak response was considered by an expert panel and the World Health Organization to have been successful. This success suggests that the Sabin-strain IPV may be a useful tool for responding to circulating VDPV2 outbreaks when high-quality supplementary immunization activities can be conducted and carefully monitored in settings with good sanitation.
Topics: Male; Child; Humans; Poliovirus; Poliovirus Vaccine, Inactivated; Wastewater; alpha-Fetoproteins; Poliomyelitis; China
PubMed: 36602797
DOI: 10.1001/jamanetworkopen.2022.49710 -
Vaccine Apr 2023Vaccine-derived polioviruses (VDPVs) can emerge from Sabin strain poliovirus serotypes 1, 2, and 3 contained in oral poliovirus vaccine (OPV) after prolonged...
Vaccine-derived polioviruses (VDPVs) can emerge from Sabin strain poliovirus serotypes 1, 2, and 3 contained in oral poliovirus vaccine (OPV) after prolonged person-to-person transmission where population vaccination immunity against polioviruses is suboptimal. VDPVs can cause paralysis indistinguishable from wild polioviruses and outbreaks when community circulation ensues. VDPV serotype 2 outbreaks (cVDPV2) have been documented in The Democratic Republic of the Congo (DRC) since 2005. The nine cVDPV2 outbreaks detected during 2005-2012 were geographically-limited and resulted in 73 paralysis cases. No outbreaks were detected during 2013-2016. During January 1, 2017-December 31, 2021, 19 cVDPV2 outbreaks were detected in DRC. Seventeen of the 19 (including two first detected in Angola) resulted in 235 paralysis cases notified in 84 health zones in 18 of DRC's 26 provinces; no notified paralysis cases were associated with the remaining two outbreaks. The DRC-KAS-3 cVDPV2 outbreak that circulated during 2019-2021, and resulted in 101 paralysis cases in 10 provinces, was the largest recorded in DRC during the reporting period in terms of numbers of paralysis cases and geographic expanse. The 15 outbreaks occurring during 2017-early 2021 were successfully controlled with numerous supplemental immunization activities (SIAs) using monovalent OPV Sabin-strain serotype 2 (mOPV2); however, suboptimal mOPV2 vaccination coverage appears to have seeded the cVDPV2 emergences detected during semester 2, 2018 through 2021. Use of the novel OPV serotype 2 (nOPV2), designed to have greater genetic stability than mOPV2, should help DRC's efforts in controlling the more recent cVDPV2 outbreaks with a much lower risk of further seeding VDPV2 emergence. Improving nOPV2 SIA coverage should decrease the number of SIAs needed to interrupt transmission. DRC needs the support of polio eradication and Essential Immunization (EI) partners to accelerate the country's ongoing initiatives for EI strengthening, introduction of a second dose of inactivated poliovirus vaccine (IPV) to increase protection against paralysis, and improving nOPV2 SIA coverage.
Topics: Humans; Poliovirus; Serogroup; Democratic Republic of the Congo; Poliomyelitis; Poliovirus Vaccine, Oral; Disease Outbreaks
PubMed: 36907733
DOI: 10.1016/j.vaccine.2023.02.042