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"widespread circulation and evolution of independent lineages of vaccine-derived polioviruses took place in the region"
Korotkova et al 2003
"In the short term, the strategy is based on the assumption that OPV is excreted by the primary vaccinees only for relatively short periods of time, e.g., up to 2 to 3 months. However, the excretion may sometimes last significantly longer and, in very rare cases of immunodeficient persons, it may continue for years (1, 2, 13, 18, 22). The long-term excretors could represent a serious and increasing hazard for the growing susceptible population"
"vaccine-associated paralytic poliomyelitis, which occur at a rate of one case per 1,000,000 cases"
"Among the options under consideration is the complete and coordinated cessation of vaccination with the live oral poliovirus vaccine soon after the world is certified free from circulating wild polioviruses"
"OPV immunization in Byelorussia (a republic within the former USSR) was started in 1959. From 1961 to 1966, two rounds of a mass nationwide campaign of immunization with trivalent vaccine were carried out; all children were immunized, with the coverage of >90%.
To evaluate the duration of OPV-induced immunity (and under the theory prevailing at the time that OPV strains could not regain neurovirulence [cf. reference 28]), children in the city of Mogilev and Mogilev District (a total population of ∼160,000) were not immunized from March 1963 to March 1966, except for 40 children in six nurseries that received a dose of trivalent OPV each in March 1965 (9). We present here evidence of the widespread circulation of the OPV-derived polioviruses within a nonimmunized community."
"A serum survey for anti-poliovirus antibodies had also been conducted (9). Here, we were interested in unvaccinated children born at least 1 year after cessation of the OPV usage (and hence containing no maternal antibodies), i.e., the cohorts of 1 to 2 years of age in 1965 and 1 to 3 years of age in 1966 (the latter group were investigated before the resumption of vaccination). Of 57 such children (none of whom were from the nurseries where OPV was intentionally reintroduced in 1965), poliovirus type 2 neutralizing antibodies with titers of 1:8 or higher were detected in 21 children (37%), supporting the notion of wide circulation of this serotype. In addition, antibodies to poliovirus serotypes 1 and 3 were detected in nine (15%) and eight (14%) of these children, respectively. Although the investigated group was rather small, the results suggest that infection with all of the three poliovirus serotypes frequently occurred during the nonvaccination period."
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464 persons became paralysed and, at least 90,000 people were infected with a vaccine strain of polio.
The Vaccine Origin of the 1968 Epidemic of Type 3 Poliomyelitis in Poland
Martin et al 2000
"A clear association was demonstrated between the use of USOL-D-bac type 3 poliovirus live-attenuated vaccine and the
1968 poliomyelitis epidemic in Poland. The epidemic followed small-scale trials with Sabin and USOL-D-bac type 3 vaccine
strains carried out in seven countries including Poland. Factors that might have contributed to the genesis and development
of the epidemic were the pattern of virus excretion from vaccinees, mutations found in viruses from the epidemic, and the
particular vaccination policies in Poland during the previous years. These findings may provide essential insights into the
strategies for stopping polio immunisation once wild poliovirus has been eradicated."
"This will eventually lead to the obvious need to stop
polio vaccination, particularly with live-attenuated vaccine
strains (20). However, some issues regarding the
scientific basis on how and when to stop polio immunisation
are still not satisfactorily answered (3, 20). One of
the most important questions is whether vaccine-derived
isolates, which would be the last strains of poliovirus to
subsist, would survive for long periods in the human
population and/or in the environment and would be able
to infect nonimmune children in the postvaccination era,
reinitiating poliomyelitis epidemics"
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"Hager contracted the disease from the vaccine and nearly died"
But when his infant son was inoculated against polio with the live-virus Sabin vaccine in August 1973, Hager contracted the disease from the vaccine and nearly died. After four months of hospitalization and rehabilitation, he emerged–without the use of his legs–to a new life.
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"patients with vaccine-associated paralytic poliomyelitis."
Attenuated strains of the Sabin oral poliovirus vaccine replicate in the human gut and in rare cases cause vaccine-associated paralytic poliomyelitis (VAPP). Reversion of vaccine strains toward a pathogenic phenotype is probably one of the main causes of VAPP, a disease most frequently associated with type 3 and type 2 strains and more rarely with the type 1 (Sabin 1) strain. To identify the determinants and mechanisms of safety versus pathogenicity of the Sabin 1 strain, we characterized the genetic and phenotypic changes in six Sabin 1-derived viruses isolated from immunocompetent patients with VAPP. The genomes of these strains carried either few or numerous mutations from the original Sabin 1 genome. As assessed in transgenic mice carrying the human poliovirus receptor (PVR-Tg mice), all but one strain had lost the attenuated phenotype. Four strains presented only a moderate neurovirulent phenotype, probably due at least in part to reversions to the wild-type genotype, which were detected in the 5' noncoding region of the genome. The reversions found in most strains at nucleotide position 480, are known to be associated with an increase in neurovirulence. The construction and characterization of Sabin 1 mutants implicated a reversion at position 189, found in one strain, in the phenotypic change. The presence of 71 mutations in one neurovirulent strain suggests that a vaccine-derived strain can survive for a long time in humans. Surprisingly, none of the strains analyzed were as neurovirulent to PVR-Tg mice as was the wild-type parent of Sabin 1 (Mahoney) or a previously identified neurovirulent Sabin 1 mutant selected at a high temperature in cultured cells. Thus, in the human gut, the Sabin 1 strain does not necessarily evolve toward the genetic characteristics and high neuropathogenicity of its wild-type parent.
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Circulation of Endemic Type 2 Vaccine-Derived Poliovirus in Egypt from 1983 to 1993
Evidence is growing that wild type 2 poliovirus has already been eradicated (7, 72, 73). The last reported human infection with indigenous wild type 2 poliovirus was associated with a poliomyelitis (polio) case in Aligarh, Uttar Pradesh, India, in October 1999 (73). Apart from a recent localized breach in containment of type 2 poliovirus (MEF-1 strain) in northern India (74), the only known current type 2 poliovirus infections are from the oral poliovirus vaccine (OPV) itself.
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Spread of Vaccine-Derived Poliovirus from a Paralytic Case in an Immunodeficient Child
"The first spreading outbreak of a vaccine-derived strain, in which 22 children were paralyzed, was detected in 2001 in the Dominican Republic and Haiti." - NYT
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Reemergence of recombinant vaccine-derived poliovirus outbreak in Madagascar.
From May to August 2005, a total of 5 cases of acute flaccid paralysis were reported among unvaccinated or partially vaccinated children 2-3 years old. Type-3 or type-2 VDPV was isolated from case patients and from healthy contacts. These strains were classified into 4 recombinant lineages that showed complex mosaic genomic structures originating from different vaccine strain serotypes and probably from human enterovirus C (HEV-C) species. Genetic relatedness could be observed among these 4 lineages. Vaccination coverage of the population was very low (<50%).
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type 1 vaccine-derived poliovirus in the Philippines in 2001
In 2001, highly evolved type 1 circulating vaccine-derived poliovirus (cVDPV) was isolated from three acute flaccid paralysis patients and one contact from three separate communities in the Philippines. Complete genomic sequencing of these four cVDPV isolates revealed that the capsid region was derived from the Sabin 1 vaccine strain but most of the noncapsid region was derived from an unidentified enterovirus unrelated to the oral poliovirus vaccine (OPV) strains. The sequences of the cVDPV isolates were closely related to each other, and the isolates had a common recombination site. Most of the genetic and biological properties of the cVDPV isolates were indistinguishable from those of wild polioviruses. However, the most recently identified cVDPV isolate from a healthy contact retained the temperature sensitivity and partial attenuation phenotypes. The sequence relationships among the isolates and Sabin 1 suggested that cVDPV originated from an OPV dose given in 1998 to 1999 and that cVDPV circulated along a narrow chain of transmission. Type 1 cVDPV was last detected in the Philippines in September 2001, and population immunity to polio was raised by extensive OPV campaigns in late 2001 and early 2002.
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Transmission of Imported Vaccine-Derived Poliovirus in an Undervaccinated Community in Minnesota
Phylogenetic analysis suggested that the Vacine Derived Polio Virus (VDPV) circulated in the community for roughly 2 months before the infant's infection was detected and that the initiating Oral Polio Vaccine dose had been given before her birth. No paralytic disease was found in the community, and no poliovirus infections were found in other Amish communities investigated.
Conclusions. This is the first demonstrated transmission of Vaccine-Derived Poliovirus in an undervaccinated community in a developed country.
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315 cases of type 2 circulating vaccine-derived poliovirus occurred during July 2005–June 2010
Wild poliovirus has remained endemic in northern Nigeria because of low coverage achieved in the routine immunization program and in supplementary immunization activities (SIAs). An outbreak of infection involving 315 cases of type 2 circulating vaccine-derived poliovirus (cVDPV2; >1% divergent from Sabin 2) occurred during July 2005–June 2010, a period when 23 of 34 SIAs used monovalent or bivalent oral poliovirus vaccine (OPV) lacking Sabin 2. In addition, 21 “pre-VDPV2” (0.5%–1.0% divergent) cases occurred during this period. Both cVDPV and pre-VDPV cases were clinically indistinguishable from cases due to wild poliovirus. The monthly incidence of cases increased sharply in early 2009, as more children aged without trivalent OPV SIAs. Cumulative state incidence of pre-VDPV2/cVDPV2 was correlated with low childhood immunization against poliovirus type 2 assessed by various means. Strengthened routine immunization programs in countries with suboptimal coverage and balanced use of OPV formulations in SIAs are necessary to minimize risks of VDPV emergence and circulation.
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DEMOCRATIC REPUBLIC OF CONGO, CIRCULATING VACCINE DERIVED POLIOVIRUS
The last confirmed wild poliovirus (WPV) case in Democratic Republic of Congo (DRC) had paralysis onset in December 2011 (1). DRC has had cases of vaccine-derived polioviruses (VDPVs) documented since 2004.
2011-2012: 30 cases of VDPVs
2013-2016: 5 cases of VDPVs
2017: 25 cses of VDPVs, 1 VDPV2 case, 1 ambiguous VDPV type 1 (aVDPV1)
During 2004-2017 (as of [8 Mar 2018]), 11 of DRC's 26 provinces reported 118 cases of acute flaccid paralysis (AFP) with VDPVs isolated in stool samples.
Tanganyika aVDPV1 Event, 2017:
DRC's single case of VDPV1 was reported in April 2017 (Figure) (6). The patient had paralysis onset on [1 Apr 2017] in Tanganyika's Ankoro health zone. The VDPV1 from this case had 25 nucleotide differences in the VP1 region from Sabin virus type 1, suggesting prolonged undetected replication. No additional VDPV1 viruses have been isolated, and the patient is not known to have an immunodeficiency; thus, to date, the case has been classified as an aVDPV1, and the occurrence is classified as a VDPV1 event per WHO's standard operating procedures
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NIGER: CIRCULATING VACCINE-DERIVED POLIOVIRUS (CVDPV)
Two cases of circulating vaccine-derived poliovirus type 2 (cVDPV2) have been reported from Zinder province, in the south of Niger [1]. The dates of onset of paralysis were 18 July and 8 August, 2018. The cases are genetically linked to a cVDPV2 in Jigawa, northern Nigeria [1]. Surveillance for further cases is being strengthened and an outbreak response will be implemented [2].
Circulating vaccine-derived poliovirus, like wild poliovirus (WPV), has the potential to cause paralysis in unvaccinated or partially vaccinated individuals
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Circulating vaccine-derived poliovirus type 2 – Nigeria
On 5 June 2018, a circulating vaccine-derived poliovirus type 2 (cVDPV2) outbreak was confirmed in Sokoto State, Nigeria. From 30 January through 23 May 2018, ten environmental samples collected from two collection sites all tested positive for genetically-related VDPV2 viruses. No associated cases of acute flaccid paralysis (AFP) have been detected with this cVDPV2.
Nigeria is also affected by an ongoing separate cVDPV2 outbreak. A cluster of cVDPV2 was detected in Yobe State from a stool sample from an AFP case with onset on 16 June 2018, and an environmental sample collected on 31 May 2018. The same cVDPV2 was detected in Gombe State from an environmental sample collected on 9 April 2018. Previously, the same cVDPV2 was detected in Jigawa State from an AFP case with onset of paralysis on 15 April 2018 and six environmental samples collected from 10 January through 2 May 2018.
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CIRCULATING VACCINE-DERIVED POLIOVIRUS TYPE 1 CONFIRMED IN PAPUA NEW GUINEA
Following identification last month of an acute flaccid paralysis (AFP) case from which vaccine-derived poliovirus type 1 (VDPV1) had been isolated, genetic sequencing of two VDPV1s from two non-household contacts of the AFP case has now confirmed that VDPV1 is circulating and is being officially classified as a ‘circulating’ VDPV type 1 (cVDPV1).
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Circulating vaccine-derived poliovirus type 2 – Somalia
Circulation of vaccine-derived poliovirus type 2 (cVDPV2) has been confirmed in Somalia. Three cVDPV2s strains were isolated from environmental samples collected on 4 and 11 January 2018, in Banadir province (Mogadishu). These latest isolates are genetically linked to cVDPV2 strains collected from environmental samples in the same province on 22 October and 2 November 2017.
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The World Health Organization says a new polio outbreak in Sudan is linked to an ongoing vaccine-sparked epidemic in Chad
LONDON -- The World Health Organization says a new polio outbreak in Sudan is linked to an ongoing vaccine-sparked epidemic in Chad — a week after the U.N. health agency declared the African continent free of the wild polio virus.
In a statement this week, WHO said two children in Sudan — one from South Darfur state and the other from Gedarif state, close to the border with Ethiopia and Eritrea — were paralyzed in March and April. Both had been recently vaccinated against polio. WHO said initial outbreak investigations show the cases are linked to an ongoing vaccine-derived outbreak in Chad that was first detected last year and is now spreading in Chad and Cameroon.
“There is local circulation in Sudan and continued sharing of transmission with Chad,” the U.N. agency said, adding that genetic sequencing confirmed numerous introductions of the virus into Sudan from Chad.
WHO said it had found 11 additional vaccine-derived polio cases in Sudan and that the virus had also been identified in environmental samples. There are typically many more unreported cases for every confirmed polio patient. The highly infectious disease can spread quickly in contaminated water and most often strikes children under 5.
In rare instances, the live polio virus in the oral vaccine can mutate into a form capable of sparking new outbreaks.
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Polio outbreaks in Africa caused by mutation of strain in vaccine
The Guardian, Dec 6, 2019. Global Development.
New cases of highly infectious disease that should be ‘consigned to the history books’ reported in Nigeria, the DRC, CAR and Angola
New cases of polio linked to the oral vaccine have been reported in four African countries and more children are now being paralysed by vaccine-derived viruses than those infected by viruses in the wild, according to global health numbers.
The World Health Organization (WHO) and partners identified nine new cases caused by the vaccine in Nigeria, the Democratic Republic of the Congo, Central African Republic and Angola last week. Along with seven other African countries with outbreaks, cases have also been reported in Asia. In Afghanistan and Pakistan polio remains endemic, and in Pakistan officials have been accused of covering up vaccine-related cases.
The onset has been caused by a type 2 virus contained in the vaccine. Type 2 is a wild virus that was eliminated years ago, but in rare cases the live virus in oral polio vaccines can mutate into a form capable of igniting new outbreaks of the disease.
"Dr Pascal Mkanda, head of the WHO’s Polio Eradication Programme, said the latest outbreak was directly linked to low vaccination rates. The rise in vaccine-derived polio cases is caused by a mutated form of the disease found in faecal matter that targets children who have not been vaccinated, he said." (thus the vaccue both prevents and causes the disease. If they were not vaccinating thw disease would not break out)
Global development is supported by
Bill and Melinda Gates Foundation
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Edna Mohamed
Thu 28 Nov 2019 13.04 GMT Last modified on Thu 28 Nov 2019 15.51 GMT
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One child gets polio from a vaccine, infects 11 others and now 12 children are paralyzed for life by one shot of the polio vaccine, for a virus that was already extinct in that country. Government attempted to cover it up.
Pakistan accused of cover-up over fresh polio outbreak caused by the vaccine itself.
Polio exists in three different types, P1, P2, and P3, with P2 notorious as the most contagious and most vicious in its impact on those infected.
Pakistan officially declared it had entirely eradicated P2 polio but a renewed outbreak of the P2 strain came from a mismanagement of vaccines, which carry a live virus and can sometimes infect the patient with polio.
A P2 vaccine was administered accidentally and a child became a carrier for the disease. Tests on the new cases show the children are all carrying a 'vaccine-derived form" of the disease . That it, the got polio from the vaccine that contained a live virus.
Under Pakistani law, every new case of polio in the country has to be officially registered with the government, which then alerts international health bodies. “But to hide their negligence and their poor performance, Babar Bin Atta decided not disclose the cases to anyone,” said the source.
The government planned secret vaccinations after 12 children fall prey to disease. “Somewhere, somebody has inaccurately used this vaccine and because of this negligence … this virus was brought back into the environment and our children are again getting infected with P2,”.
The cases, which have all resulted in paralysis, have been discovered mainly in Diamer district, with one in the capital, Islamabad.
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