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PloS One 2014Pakistan and Afghanistan share a long uncontrolled border with extensive population movement on both sides. Wild poliovirus transmission has never been interrupted in...
Pakistan and Afghanistan share a long uncontrolled border with extensive population movement on both sides. Wild poliovirus transmission has never been interrupted in this block due to war against terrorism, poor public health infrastructure, misconceptions about polio vaccines and inadequate immunization activities. All these issues complicate the eradication operations and reinforce the complexity of wiping out poliomyelitis from this region. This study illustrates the origins and routes of cross-border wild poliovirus type 1 (WPV1) transmission during 2010-2012 between Pakistan and Afghanistan. Sequence analyses were conducted based on complete VP1 capsid protein sequences for WPV1 study strains to determine the origin of poliovirus genetic lineages and their evolutionary relationships. Phylogenetic tree was constructed from VP1 gene sequences applying Maximum Likelihood method using Kimura 2- parameter model in MEGA program v 5.0. A total of 72 (14.3%) out of 502 wild-type 1 polioviruses were found circulating in border areas of both countries during 2010-2012. Molecular phylogenetic analysis classified these strains in to two sub-genotypes with four clusters and 18 lineages. Genetic data confirmed that the most of WPV1 lineages (12; 66.6%) were transmitted from Pakistan to Afghanistan. However, the genetic diversity was significantly reduced during 2012 as most of the lineages were completely eliminated. In conclusion, Pakistan-Afghanistan block has emerged as a single poliovirus reservoir sharing the multiple poliovirus lineages due to uncontrolled movement of people across the borders between two countries. If it is neglected, it can jeopardize the extensive global efforts done so-far to eradicate the poliovirus infection. Our data will be helpful to devise the preventive strategies for effective control of wild poliovirus transmission in this region.
Topics: Afghanistan; Genotype; Geography; Humans; Molecular Epidemiology; Pakistan; Phylogeny; Poliomyelitis; Poliovirus
PubMed: 25229826
DOI: 10.1371/journal.pone.0107697 -
Virology Sep 1987Disoxaril [WIN 51711, 5-[7-[4(4,5-dihydro-2-oxazolyl)phenoxy]heptyl]-3- methylisoxazole] inhibits the replication of polioviruses types 1 and 2 in HeLa cells by...
Disoxaril [WIN 51711, 5-[7-[4(4,5-dihydro-2-oxazolyl)phenoxy]heptyl]-3- methylisoxazole] inhibits the replication of polioviruses types 1 and 2 in HeLa cells by stabilizing the virus capsid, which results in the inhibition of the pH-dependent viral uncoating in endosomes and/or lysosomes. As shown by electron microscopy the virus entered into the cell by receptor-mediated endocytosis via coated pits and coated vesicles into endosomes irrespective of the presence or absence of the compound. Measurements of viral RNA synthesis showed that disoxaril completely inhibited the arrival of viral RNA in the cytoplasm for new RNA synthesis only when the inocula were preincubated with disoxaril for 15 min at 37 degrees at 0.3 microgram disoxaril/ml for poliovirus type 1 and 0.03 microgram disoxaril/ml for poliovirus type 2. Simultaneous addition of the compound and virus resulted in reduced inhibition of viral RNA synthesis. The inhibitory effect of the compound could be partially reversed up to 25 min p.i. if the compound was eluted from the cells.
Topics: Antiviral Agents; Capsid; Depression, Chemical; Endocytosis; HeLa Cells; Humans; Isoxazoles; Lysosomes; Oxazoles; Poliovirus; RNA, Viral; Virus Replication
PubMed: 2820136
DOI: 10.1016/0042-6822(87)90075-4 -
Emerging Infectious Diseases Jul 2019The Global Polio Eradication Initiative continues to make progress toward the eradication target. Indigenous wild poliovirus (WPV) type 2 was last detected in 1999, WPV... (Meta-Analysis)
Meta-Analysis
The Global Polio Eradication Initiative continues to make progress toward the eradication target. Indigenous wild poliovirus (WPV) type 2 was last detected in 1999, WPV type 3 was last detected in 2012, and over the past 2 years WPV type 1 has been detected only in parts of 2 countries (Afghanistan and Pakistan). Once the eradication of poliomyelitis is achieved, infectious and potentially infectious poliovirus materials retained in laboratories, vaccine production sites, and other storage facilities will continue to pose a risk for poliovirus reintroduction into communities. The recent breach in containment of WPV type 2 in an inactivated poliovirus vaccine manufacturing site in the Netherlands prompted this review, which summarizes information on facility-associated release of polioviruses into communities reported over >8 decades. Successful polio eradication requires the management of poliovirus containment posteradication to prevent the consequences of the reestablishment of poliovirus transmission.
Topics: Animals; Biohazard Release; Disease Eradication; Global Health; Humans; Laboratories; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Inactivated; Poliovirus Vaccine, Oral
PubMed: 31082331
DOI: 10.3201/eid2507.181703 -
PloS One 2013Environmental surveillance of poliovirus on sewage has been conducted in Shandong Province, China since 2008. A type 2 vaccine-derived poliovirus (VDPV) with 7 mutations...
Environmental surveillance of poliovirus on sewage has been conducted in Shandong Province, China since 2008. A type 2 vaccine-derived poliovirus (VDPV) with 7 mutations in VP1 coding region was isolated from the sewage collected in the city of Jinan in December 2012. The complete genome sequencing analysis of this isolate revealed 25 nucleotide substitutions, 7 of which resulted in amino acid alteration. No evidence of recombination with other poliovirus serotypes was observed. The virus did not lose temperature sensitive phenotype at 40°C. An estimation based on the evolution rate of the P1 coding region suggested that evolution time of this strain might be 160-176 days. VP1 sequence analysis revealed that this VDPV strain is of no close relationship with other local type 2 polioviruses (n=66) from sewage collected between May 2012 and June 2013, suggesting the lack of its circulation in the local population. The person who excreted the virus was not known and no closely related virus was isolated in local population via acute flaccid paralysis surveillance. By far this is the first report of VDPV isolated from sewage in China, and these results underscore the value of environmental surveillance in the polio surveillance system even in countries with high rates of OPV coverage.
Topics: China; Environmental Monitoring; Evolution, Molecular; Genome, Viral; Phenotype; Phylogeny; Poliovirus; Poliovirus Vaccines; Sewage; Temperature; Vaccination
PubMed: 24386319
DOI: 10.1371/journal.pone.0083975 -
Journal of Clinical Microbiology May 1994Sixty-eight laboratory strains representing 49 enterovirus, 10 adenovirus, and 3 reovirus serotypes were inoculated in a recombinant murine cell line expressing the...
Sixty-eight laboratory strains representing 49 enterovirus, 10 adenovirus, and 3 reovirus serotypes were inoculated in a recombinant murine cell line expressing the human poliovirus receptor gene (L alpha cells). Only polioviruses caused cytopathic effect over a 10-day period. Likewise, only polioviruses were isolated, by use of L alpha cells, from 168 fecal specimens from children from developing countries. These results suggest that the recombinant L alpha cells can be used for selective isolation of poliovirus from clinical specimens.
Topics: Animals; Cell Line; Cytopathogenic Effect, Viral; Evaluation Studies as Topic; Gene Expression; Humans; Membrane Proteins; Mice; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Oral; Receptors, Virus; Virology; Virus Replication
PubMed: 8051271
DOI: 10.1128/jcm.32.5.1366-1368.1994 -
Journal of Clinical Microbiology Jul 2017Oral poliovirus vaccine can mutate to regain neurovirulence. To date, evaluation of these mutations has been performed primarily on culture-enriched isolates by using...
Oral poliovirus vaccine can mutate to regain neurovirulence. To date, evaluation of these mutations has been performed primarily on culture-enriched isolates by using conventional Sanger sequencing. We therefore developed a culture-independent, deep-sequencing method targeting the 5' untranslated region (UTR) and P1 genomic region to characterize vaccine-related poliovirus variants. Error analysis of the deep-sequencing method demonstrated reliable detection of poliovirus mutations at levels of <1%, depending on read depth. Sequencing of viral nucleic acids from the stool of vaccinated, asymptomatic children and their close contacts collected during a prospective cohort study in Veracruz, Mexico, revealed no vaccine-derived polioviruses. This was expected given that the longest duration between sequenced sample collection and the end of the most recent national immunization week was 66 days. However, we identified many low-level variants (<5%) distributed across the 5' UTR and P1 genomic region in all three Sabin serotypes, as well as vaccine-related viruses with multiple canonical mutations associated with phenotypic reversion present at high levels (>90%). These results suggest that monitoring emerging vaccine-related poliovirus variants by deep sequencing may aid in the poliovirus endgame and efforts to ensure global polio eradication.
Topics: Child, Preschool; Feces; Female; Genetic Variation; High-Throughput Nucleotide Sequencing; Humans; Infant; Male; Mexico; Mutation; Poliovirus; Poliovirus Vaccine, Oral; Prospective Studies
PubMed: 28468861
DOI: 10.1128/JCM.00144-17 -
Clinical Infectious Diseases : An... Apr 2015Israel has >95% polio vaccine coverage with the last 9 birth cohorts immunized exclusively with inactivated polio vaccine (IPV). Using acute flaccid paralysis and...
BACKGROUND
Israel has >95% polio vaccine coverage with the last 9 birth cohorts immunized exclusively with inactivated polio vaccine (IPV). Using acute flaccid paralysis and routine, monthly countrywide environmental surveillance, no wild poliovirus circulation was detected between 1989 and February 2013, after which wild type 1 polioviruses South Asia genotype (WPV1-SOAS) have persistently circulated in southern Israel and intermittently in other areas without any paralytic cases as determined by intensified surveillance of environmental and human samples. We aimed to characterize antigenic and neurovirulence properties of WPV1-SOAS silently circulating in a highly vaccinated population.
METHODS
WPV1-SOAS capsid genes from environmental and stool surveillance isolates were sequenced, their neurovirulence was determined using transgenic mouse expressing the human poliovirus receptor (Tg21-PVR) mice, and their antigenicity was characterized by in vitro neutralization using human sera, epitope-specific monoclonal murine anti-oral poliovirus vaccine (OPV) antibodies, and sera from IPV-immunized rats and mice.
RESULTS
WPV1 amino acid sequences in neutralizing epitopes varied from Sabin 1 and Mahoney, with little variation among WPV1 isolates. Neutralization by monoclonal antibodies against 3 of 4 OPV epitopes was lost. Three-fold lower geometric mean titers (Z = -4.018; P < .001, Wilcoxon signed-rank test) against WPV1 than against Mahoney in human serum correlated with 4- to 6-fold lower neutralization titers in serum from IPV-immunized rats and mice. WPV1-SOAS isolates were neurovirulent (50% intramuscular paralytic dose in Tg21-PVR mice: log10(7.0)). IPV-immunized mice were protected against WPV1-induced paralysis.
CONCLUSIONS
Phenotypic and antigenic profile changes of WPV1-SOAS may have contributed to the intense silent transmission, whereas the reduced neurovirulence may have contributed to the absence of paralytic cases in the background of high population immunity.
Topics: Adolescent; Adult; Aged; Animals; Antigens, Viral; Capsid Proteins; Child; Child, Preschool; Environmental Microbiology; Feces; Female; Genotype; Humans; Israel; Male; Mice, Transgenic; Middle Aged; Molecular Sequence Data; Neutralization Tests; Phenotype; Poliovirus; Rats, Wistar; Sequence Analysis, DNA; Sequence Homology; Virulence; Young Adult
PubMed: 25550350
DOI: 10.1093/cid/ciu1136 -
Vaccine Aug 2017The European Region, certified polio-free in 2002, remains at risk of wild poliovirus reintroduction and emergence of circulating vaccine-derived polioviruses (cVDPV)... (Review)
Review
BACKGROUND
The European Region, certified polio-free in 2002, remains at risk of wild poliovirus reintroduction and emergence of circulating vaccine-derived polioviruses (cVDPV) until global polio eradication is achieved, as demonstrated by the cVDPV1 outbreak in Ukraine in 2015.
METHODS
We reviewed epidemiologic, clinical and virology data on cVDPV cases, surveillance and immunization coverage data, and reports of outbreak-related surveys, country missions, and expert group meetings.
RESULTS
In Ukraine, 3-dose polio vaccine coverage declined from 91% in 2008 to 15% by mid-2015. In summer, 2015, two unrelated children from Zakarpattya province were paralyzed by a highly divergent cVDPV1. The isolates were 20 and 26 nucleotide divergent from prototype Sabin strain (with 18 identical mutations) consistent with their common origin and ∼2-year evolution. Outbreak response recommendations developed with international partner support included conducting three nationwide supplementary immunization activities (SIAs) with tOPV, strengthening surveillance and implementing communication interventions. SIAs were conducted during October 2015-February 2016 (officially reported coverage, round 1-64.4%, round 2-71.7%, and round 3-80.7%). Substantial challenges to outbreak response included lack of high-level support, resistance to OPV use, low perceived risk of polio, widespread vaccine hesitancy, anti-vaccine media environment, economic crisis and military conflict. Communication activities improved caregiver awareness of polio and confidence in vaccination. Surveillance was enhanced but did not consistently meet applicable performance standards. Post-outbreak assessments concluded that cVDPV1 transmission in Ukraine has likely stopped following the response, but significant gaps in population immunity and surveillance remained.
CONCLUSIONS
Chronic under-vaccination in Ukraine resulted in the accumulation of children susceptible to polioviruses and created favorable conditions for VDPV1 emergence and circulation, leading to the outbreak. Until programmatic gaps in immunization and surveillance are addressed, Ukraine will remain at high-risk for VDPV emergence and circulation, as well as at risk for other vaccine-preventable diseases.
Topics: Adolescent; Child; Disease Eradication; Disease Outbreaks; Female; Humans; Infant; Male; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Oral; Poliovirus Vaccines; Ukraine; Vaccination; Vaccination Refusal
PubMed: 28528761
DOI: 10.1016/j.vaccine.2017.04.036 -
Kansenshogaku Zasshi. the Journal of... Feb 2003Outbreaks of gastroenteritis caused by Norwalk-like viruses are often induced by the consumption of raw shellfish such as oysters. Incidences reach a peak during the...
Outbreaks of gastroenteritis caused by Norwalk-like viruses are often induced by the consumption of raw shellfish such as oysters. Incidences reach a peak during the cold season in Japan, when seawater temperatures fall below 10 degrees C. We investigated oysters' uptake and excretion of viruses, over varying lengths of exposure, monitoring the effects of changes in temperature and flow rate of seawater, and the presence of plankton. The study was performed using a poliovirus and an experimental circulatory system, which was framed on the same principle as a model practically used for the depuration of oysters. Polioviruses present in the seawater were taken rapidly into the midgut gland of oysters. However, virus levels detected in oysters at both 10 degrees C and 20 degrees C were decreased to approximately 1/1,000 to 1/10,000 within 6 hrs after the circulatory seawater was replaced by UV irradiated seawater. These results demonstrate the effectiveness of the circulatory depuration system for the elimination of poliovirus from oysters, and indicate that controlling the temperature and flow rate of the circulatory system could decrease the risk of NLV infection.
Topics: Animals; Decontamination; Food Microbiology; Norovirus; Ostreidae; Poliovirus; Seawater; Shellfish; Temperature; Ultraviolet Rays
PubMed: 12661085
DOI: 10.11150/kansenshogakuzasshi1970.77.95 -
BMC Infectious Diseases Sep 2015Prior analyses demonstrated the need for some countries and the Global Polio Eradication Initiative (GPEI) to conduct additional supplemental immunization activities...
BACKGROUND
Prior analyses demonstrated the need for some countries and the Global Polio Eradication Initiative (GPEI) to conduct additional supplemental immunization activities (SIAs) with trivalent oral poliovirus vaccine (tOPV) prior to globally-coordinated cessation of all serotype 2-containing OPV (OPV2 cessation) to prevent the creation of serotype 2 circulating vaccine-derived poliovirus (cVDPV2) outbreaks after OPV2 cessation. The GPEI continues to focus on achieving and ensuring interruption of wild poliovirus serotype 1 (WPV1) and making vaccine choices that prioritize bivalent OPV (bOPV) for SIAs, nominally to increase population immunity to serotype 1, despite an aggressive timeline for OPV2 cessation.
METHODS
We use an existing dynamic poliovirus transmission model of northwest Nigeria and an integrated global model for long-term poliovirus risk management to explore the impact of tOPV vs. bOPV vaccine choices on population immunity and cVDPV2 risks.
RESULTS
Using tOPV instead of bOPV for SIAs leads to a minimal decrease in population immunity to transmission of serotypes 1 and 3 polioviruses, but a significantly higher population immunity to transmission of serotype 2 polioviruses. Failure to use tOPV in enough SIAs results in cVDPV2 emergence after OPV2 cessation in both the northwest Nigeria model and the global model. Despite perceptions to the contrary, prioritizing the use of bOPV over tOPV prior to OPV2 cessation does not significantly improve serotype 1 population immunity to transmission.
CONCLUSIONS
Immunization leaders need to focus on all three poliovirus serotypes to appropriately manage the risks of OPV cessation in the polio endgame. Focusing on population immunity to transmission to interrupt WPV1 transmission and manage pre-OPV cessation risks of cVDPVs, all countries performing poliovirus SIAs should use tOPV up until the time of OPV2 cessation, after which time they should continue to use the OPV vaccine formulation with all remaining serotypes until coordinated global cessation of those serotypes.
Topics: Chemistry, Pharmaceutical; Disease Outbreaks; Humans; Nigeria; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Oral; Risk Management; Serogroup; Vaccination
PubMed: 26382234
DOI: 10.1186/s12879-015-1116-4