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Circulation of a type 2 vaccine-derived poliovirus--Egypt, 1982-1993.

In 1988, the World Health Assembly resolved to eradicate poliomyelitis globally by 2000. Substantial progress has been achieved toward this goal, and with the circulation of wild poliovirus eliminated in most of the world, attention has focused on examining the potential for vaccine-derived poliovirus to circulate where wild poliovirus has disappeared. During 1999, sequences of historic poliovirus isolates were examined. This report summaries the results of that study, which indicate that oral poliovirus vaccine (OPV)-derived poliovirus type 2 circulated in Egypt during the 1980s and early 199…

Acute flaccid paralysis associated with circulating vaccine-derived poliovirus--Philippines, 2001.

Three cases of acute flaccid paralysis (AFP) associated with circulating vaccine-derived poliovirus (cVDPV) isolates were reported in the Philippines during March 15-July 26, 2001. The first case-patient, a child aged 8 years from northern Mindanao island (500 miles south of Manila) who had received 3 doses of oral polio vaccine (OPV), had onset of paralysis on March 15. A second child, aged 3 years from Laguna province on Luzon island (60 miles south of Manila) who had received 3 OPV doses, presented with signs of meningitis but no paralysis on July 23. A third child, aged 14 months from Cavi…

Characteristics of poliovirus strains from long-term excretors with primary immunodeficiencies.

Individuals who are deficient in humoral immunity are particularly at risk from infection with enteroviruses, and poliovirus in particular, where antibodies are the main source of protection from disease. Long-term excretion of vaccine strains of poliovirus has been documented for many years and instances of paralytic poliomyelitis in hypogammaglobulinaemic patients who were subsequently found to have been excreting virus for prolonged periods have been reported in the U.S.A., Germany and Japan. The identification of a healthy immunodeficient patient in the U.K. who has probably been excreting…

Intratypic differentiation & partial nucleotide sequencing of poliovirus isolates of northern India.

The potential resolving power of molecular epidemiological studies has enhanced the precision and reliability of poliovirus (PV) surveillance. PV has an error prone RNA polymerase responsible for rapid evolution of genome (approximately 10(-2) nt substitution/site/year), during inter and intra-human passages. The present study included a serotyped panel of 60 PV (42 PV type-1, 13 PV type-2 and 5 PV type-3) isolated during 1997. They were differentiated into vaccine (Sabin) and wild strains by two methods viz., genotype specific RNA probe hybridization (Rpro-Hy) based on genotypic variability; …

Recovery of poliovirus from cut surface of stored fresh papaya fruit.

Poliovirus kept on the cut surfaces of fully ripe papaya cubes placed in an ice box showed a sharp and significant reduction in the recovery of infectious virus about 15 minutes after exposure. Thereafter, a very gradual decrease ensued and infectious residual virus was detected up to the end of the 6-hour exposure period. Papaya cubes washed or kept overnight before virus inoculation, and from less ripe fruits produced a similar survival pattern. A very small proportion of the inoculum was recovered from the mashed content of the inoculated papaya cubes thus suggesting that most of the non-re…

Internal ribosomal entry site substitution eliminates neurovirulence in intergeneric poliovirus recombinants.

Neuropathogenicity of poliovirus can be attenuated by mutations in the internal ribosomal entry site (IRES) within the 5' nontranslated region of its genome. The Sabin vaccine strains used in prevention of poliomyelitis carry such mutations in their IRES elements. In addition, mutations within the structural and nonstructural proteins of Sabin strains may equally contribute to the attenuation phenotype. Despite their effectiveness as vaccines, the Sabin strains retain a neuropathogenic potential in animal models for poliomyelitis and, at a very low rate, they can cause poliomyelitis in vaccine…

Update: mass vaccination with oral poliovirus vaccine--Asia and Europe, 1996.

In 1995, a group of 18 geographically contiguous countries in Europe, Central and South Asia, and the Middle East cooperated in conducting coordinated National Immunization Days (NIDs) with oral poliovirus vaccine (OPV). The World Health Organization (WHO) had designated this effort "Operation MECACAR" (MEditerranean, CAucasus, and Central Asian Republics). Operation MECACAR was repeated in 1996 with the addition of the Russian Federation. This report describes OPV coverage achieved during the mass vaccination campaign in 1996 and summarizes the impact of the NIDs on poliomyelitis incidence du…

Neurovirulence test for oral live poliovaccines using poliovirus-sensitive transgenic mice.

The transgenic mice, ICR-PVRTg21, carrying the human poliovirus receptor gene, were intraspinally inoculated with oral poliovirus vaccine viruses and the viruses that had been derived from a vaccine preparation by passagings at 38 degrees. Dose-dependent incidence of paralysis was observed in the transgenic mice inoculated with any of the viruses used. All transgenic mice showing histopathological lesions in the central nervous system appeared to display clinical signs that resembled those observed in human poliomyelitis. These suggest that relative neurovirulence levels of individual virus pr…

A Randomized Phase 4 Study of Immunogenicity and Safety After Monovalent Oral Type 2 Sabin Poliovirus Vaccine Challenge in Children Vaccinated with Inactivated Poliovirus Vaccine in Lithuania.

BACKGROUND: Understanding immunogenicity and safety of monovalent type 2 oral poliovirus vaccine (mOPV2) in inactivated poliovirus vaccine (IPV)-immunized children is of major importance in informing global policy to control circulating vaccine-derived poliovirus outbreaks. METHODS: In this open-label, phase 4 study (NCT02582255) in 100 IPV-vaccinated Lithuanian 1-5-year-olds, we measured humoral and intestinal type 2 polio neutralizing antibodies before and 28 days after 1 or 2 mOPV2 doses given 28 days apart and measured stool viral shedding after each dose. Parents recorded solicited adver…

Safety and immunogenicity of two novel type 2 oral poliovirus vaccine candidates compared with a monovalent type 2 oral poliovirus vaccine in healthy adults: two clinical trials.

BACKGROUND: Two novel type 2 oral poliovirus vaccine (OPV2) candidates, novel OPV2-c1 and novel OPV2-c2, designed to be more genetically stable than the licensed Sabin monovalent OPV2, have been developed to respond to ongoing polio outbreaks due to circulating vaccine-derived type 2 polioviruses. METHODS: We did two randomised studies at two centres in Belgium. The first was a phase 4 historical control study of monovalent OPV2 in Antwerp, done before global withdrawal of OPV2, and the second was a phase 2 study in Antwerp and Ghent with novel OPV2-c1 and novel OPV2-c2. Eligible participants…

Combined immunization of infants with oral and inactivated poliovirus vaccines: results of a randomized trial in The Gambia, Oman, and Thailand. WHO Collaborative Study Group on Oral and Inactivated Poliovirus Vaccines.

To assess an immunization schedule combining oral (OPV) and inactivated poliovirus vaccines (IPV), we conducted a clinical trial in the Gambia, Oman, and Thailand. Children were randomized to receive one of the following schedules: OPV at birth, 6, 10, and 14 weeks of age; OPV at birth followed by both OPV and IPV at 6, 10, and 14 weeks of age: or placebo at birth followed by IPV at 6, 10, and 14 weeks of age. A total of 1685 infants were enrolled; 24-week serum specimens were available for 1291 infants (77%). Across the study sites at 24 weeks of age, the proportion of seropositive children i…

Intestinal mucosal immune responses induced by novel oral poliovirus vaccine type 2 and Sabin monovalent oral poliovirus vaccine type 2: an analysis of data from four clinical trials.

BACKGROUND: A novel oral polio vaccine type 2 (nOPV2), which is more genetically stable (ie, lower risks of reverting to neurovirulence) than the Sabin monovalent OPV2 (mOPV2), has been deployed to interrupt circulating vaccine-derived poliovirus type 2 (PV2) outbreaks. This study compares intestinal mucosal immune responses induced by nOPV2 and mOPV2. METHODS: In this analysis, we evaluated intestinal mucosal immune responses in healthy participants of different ages (ie, infants aged 18-22 weeks, children aged 1-4 years, and adults aged 18-50 years) and vaccine backgrounds (ie, OPV2-experie…

First report of a persistent oropharyngeal infection of type 2 vaccine-derived poliovirus (iVDPV2) in a primary immune deficient (PID) patient after eradication of wild type 2 poliovirus.

This is the first report of persistent oropharyngeal mucosal infection with type 2 poliovirus (iVDPV2) in a primary immune deficient patient (PID) after wild type 2 poliovirus eradication. The iVDPV2 also established persistence in the gut. iVDPV2 at both loci evolved independently. Persistent oral infections present a potential risk for oral-oral as well as fecal-oral poliovirus transmission during transition to a poliovirus 2-free world.

Inactivated poliovirus vaccine alone or sequential inactivated and oral poliovirus vaccine in two-, four- and six-month-old infants with combination Haemophilus influenzae type b/hepatitis B vaccine.

BACKGROUND: Advisory committees have recommended the increased use of inactivated poliovirus vaccine (IPV) for children. OBJECTIVES: The purpose of this study was to assess the safety and immunogenicity of three schedules using IPV administered with diphtheria and tetanus toxoids and whole cell pertussis vaccines in a dual-chambered syringe. Children also received a combination of Haemophilus influenzae type b (Hib) and hepatitis B vaccines (COMVAX). METHODS: All infants (n = 295) received IPV and COMVAX at 2 and 4 months of age and IPV, oral poliovirus vaccine (OPV) or both vaccines at 6 mo…

Tissue-specific replicating capacity of a chimeric poliovirus that carries the internal ribosome entry site of hepatitis C virus in a new mouse model transgenic for the human poliovirus receptor.

Nucleotides (nt) 108 to 742 of an infectious cDNA clone of poliovirus (PV) Mahoney strain, including the corresponding region of the internal ribosome entry site (IRES), was replaced by nt 28 to 710 of hepatitis C virus (HCV) cDNA corresponding to the whole HCV IRES. A chimeric PV (2A-369) was generated by transfecting mammalian cells with an RNA transcribed in vitro from the cDNA. To examine replicating capacity of virus 2A-369 in the brain and liver of a mouse model for poliomyelitis, a new mouse model (MPVRTg25-61) that is transgenic for human PV receptor (hPVR; CD155) was generated in orde…

Профилактика полиомиелита в Соединенных Штатах: введение последовательного графика вакцинации вакцины против полиомиелита с неактивированной полиомиелитной вакциной с последующей пероральной вакциной против полиомиелита. Рекомендации Консультативного комитета по практике иммунизации.

Эти пересмотренные рекомендации Консультативного комитета по практике иммунизации (КККП) заменяют рекомендации по полиомиелиту, опубликованные в 1982 и 1987 годах, и представляют собой новую политику вакцинации от полиомиелита, которая усиливает зависимость от неактивированной вакцины против полиомиелита (ИПВ). Это изменение в политике является наиболее существенным с момента введения пероральной вакцины против полиомиелита (ОВП) в 1961 году. АКИП пришел к выводу о том, что соотношение < < риск-выгоды > > , связанное с исключительным использованием ППВ для плановой иммунизации, изм

Совпадение в аннотации оригинала
These revised recommendations of the Advisory Committee on Immunization Practices (ACIP) replace recommendations on poliomyelitis issued in 1982 and 1987, and present a new ACIP poliovirus vaccination policy that increases reliance on inactivated poliovirus vaccine (IPV). This change in policy is the most substantive since the introduction of oral poliovirus…