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Bessaud M.,Aix - Marseille University | Razafindratsimandresy R.,Institute Pasteur Of Madagascar | Nougairede A.,Aix - Marseille University | Joffret M.-L.,Institute Pasteur Paris | And 9 more authors.
PLoS ONE | Year: 2014

Most circulating strains of Human enterovirus 71 (EV-A71) have been classified primarily into three genogroups (A to C) on the basis of genetic divergence between the 1D gene, which encodes the VP1 capsid protein. The aim of the present study was to provide further insights into the diversity of the EV-A71 genogroups following the recent description of highly divergent isolates, in particular those from African countries, including Madagascar. We classified recent EV-A71 isolates by a large comparison of 3,346 VP1 nucleotidic sequences collected from GenBank. Analysis of genetic distances and phylogenetic investigations indicated that some recently-reported isolates did not fall into the genogroups A-C and clustered into three additional genogroups, including one Indian genogroup (genogroup D) and 2 African ones (E and F). Our Bayesian phylogenetic analysis provided consistent data showing that the genogroup D isolates share a recent common ancestor with the members of genogroup E, while the isolates of genogroup F evolved from a recent common ancestor shared with the members of the genogroup B. Our results reveal the wide diversity that exists among EV-A71 isolates and suggest that the number of circulating genogroups is probably underestimated, particularly in developing countries where EV-A71 epidemiology has been poorly studied. © 2014 Bessaud et al. Source

Hovi T.,Finnish National Institute for Health and Welfare | Shulman L.M.,Sheba Medical Center | Van Der Avoort H.,National Institute of Public Health and the Environment RIVM | Deshpande J.,Enterovirus Research Center | And 2 more authors.
Epidemiology and Infection | Year: 2012

Environmental poliovirus surveillance (ENV) means monitoring of poliovirus (PV) transmission in human populations by examining environmental specimens supposedly contaminated by human faeces. The rationale is based on the fact that PV-infected individuals, whether presenting with disease symptoms or not, shed large amounts of PV in the faeces for several weeks. As the morbidity: infection ratio of PV infection is very low, this fact contributes to the sensitivity of ENV which under optimal conditions can be better than that of the standard acute flaccid paralysis (AFP) surveillance. The World Health Organization has included ENV in the new Strategic Plan of the Global Polio Eradication Initiative for years 2010-2012 to be increasingly used in PV surveillance, supplementing AFP surveillance. In this paper we review the feasibility of using ENV to monitor wild PV and vaccine-derived PV circulation in human populations, based on global experiences in defined epidemiological situations. © 2011 Cambridge University Press and World Health Organization. Source

De Silva R.,Medical Research Institute | Gunasena S.,Medical Research Institute | Ratnayake D.,Medical Research Institute | Wickremesinghe G.D.,Medical Research Institute | And 5 more authors.
Vaccine | Year: 2012

Background: The Global Polio Eradication Initiative, established in 1988, has made substantial progress toward achieving this target, with only 3 countries never having eliminated wild poliovirus. Persons with primary immune deficiency disorders (PIDD) exposed to OPV are at increased risk of vaccine-associated paralytic poliomyelitis (VAPP) and of prolonged excretion of Sabin polioviruses. However, the risk for prolonged excretion is not known. Therefore, we studied the prevalence of PIDD with long-term poliovirus excretion in Sri Lanka, a middle income country currently using OPV. Methods: We stimulated the referral of patients under the age of 35 years, with clinical features suggestive of immune deficiency to the single immunology clinic in the country, where these patients were investigated for the presence of PIDD. Stool samples from patients with PIDD were cultured for the presence of poliovirus (PV). Poliovirus isolates were tested for intratypic differentiation (ITD). The VP1 region of all poliovirus isolates was sequenced. Results: Of 942 patients investigated, 51 (5.4%) were diagnosed with PIDD. Five (10.2%) patients excreted poliovirus. A patient with X linked agammaglobulinemia (XLA) excreted a mixture of all three Sabin like (SL) poliovirus serotypes. One patient with severe combined immune deficiency (SCID) excreted SL type 2, and another with SCID excreted SL type 3. One patient with SCID excreted a P2 vaccine-derived poliovirus (VDPV 2), and another with common variable immune deficiency (CVID) excreted a VDPV 3. The 3 patients with SCID died before scheduled collection of subsequent samples one month later, while the patient with XLA had cleared the virus in stool sample collected after 3 and 11 months. The CVID patient with VDPV 3 excreted for 7 months, and has developed a 23 nucleotide divergence in VP1 (∼900 nucleotides) from the parental Sabin virus. Conclusions: In our study, several patients with SCID, XLA and CVID excreted poliovirus. With improving health care quality patients with CVID and XLA may survive longer especially with provision of intravenous immune globulin. Regular screening of patients with PIDD for excretion of poliovirus is necessary to identify chronic excretors and make available specific therapies. © 2012 Elsevier Ltd. Source

Sutter R.W.,World Health Organization | John T.J.,India Expert Advisory Group on Polio Eradication | Jain H.,Mahatma Gandhi Memorial Medical College | Agarkhedkar S.,Dr D Y Patil Medical College | And 10 more authors.
The Lancet | Year: 2010

Poliovirus types 1 and 3 co-circulate in poliomyelitis-endemic countries. We aimed to assess the immunogenicity of a novel bivalent types 1 and 3 oral poliovirus vaccine (bOPV). We did a randomised, double-blind, controlled trial to assess the superiority of monovalent type 2 OPV (mOPV2), mOPV3, or bOPV over trivalent OPV (tOPV), and the non-inferiority of bivalent vaccine compared with mOPV1 and mOPV3. The study was done at three centres in India between Aug 6, 2008, and Dec 26, 2008. Random allocation was done by permuted blocks of ten. The primary outcome was seroconversion after one monovalent or bivalent vaccine dose compared with a dose of trivalent vaccine at birth. The secondary endpoints were seroconversion after two vaccine doses compared with after two trivalent vaccine doses and cumulative two-dose seroconversion. Parents or guardians and study investigators were masked to treatment allocation. Because of multiple comparisons, we defined p≤0·01 as statistically significant. This trial is registered with Current Controlled Trials, ISRCTN 64725429. 900 newborn babies were randomly assigned to one of five vaccine groups (about 180 patients per group); of these 70 (8) discontinued, leaving 830 (92) for analysis. After the first dose, seroconversion to poliovirus type 1 was 20 for both mOPV1 (33 of 168) and bOPV (32 of 159) compared with 15 for tOPV (25 of 168; p>0·01), to poliovirus type 2 was 21 (35 of 170) for mOPV2 compared with 25 (42 of 168) for tOPV (p>0·01), and to poliovirus type 3 was 12 (20 of 165) for mOPV3 and 7 (11 of 159) for bOPV compared with 4 (7 of 168) for tOPV (mOPV3 vs tOPV p=0·01; bOPV vs tOPV; p>0·01). Cumulative two-dose seroconversion to poliovirus type 1 was 90 (151 of 168) for mOPV1 and 86 (136 of 159) for bOPV compared with 63 (106 of 168) for tOPV (p<0·0001), to poliovirus type 2 was 90 (153 of 170) for mOPV2 compared with 91 (153 of 168) for tOPV (p>0·01), and to poliovirus type 3 was 84 (138 of 165) for mOPV3 and 74 (117 of 159) for bOPV compared with 52 (87 of 168) for tOPV (p<0·0001). The vaccines were well tolerated. 19 serious adverse events occurred, including one death; however, these events were not attributed to the trial interventions. The findings show the superiority of bOPV compared with tOPV, and the non-inferiority of bOPV compared with mOPV1 and mOPV3. GAVI Alliance, World Health Organization, and Panacea Biotec. © 2010 Elsevier Ltd. Source

Jain H.,MGM Medical College | Ravishankar K.,Niloufer Hospital | Amaresh A.,Niloufer Hospital | Verma H.,World Health Organization | And 8 more authors.
Vaccine | Year: 2011

Background: To provide the polio eradication initiative with more immunogenic oral poliovirus vaccines (OPVs), we evaluated newly developed monovalent type 1 OPV (mOPV1) among infants in India. Methods: Two double-blind randomized controlled clinical trials compared two mOPV1s (mOPV1 A and mOPV1 B) versus trivalent OPV (tOPV X) given at birth (trial I), or assessed two products of higher-potency mOPV1 (mOPV1 C and mOPV1 D) versus regular-potency mOPV1 (mOPV1 B) or tOPV Y given at birth and at 30 days (trial II). Results: In trial I, 597 newborns were enrolled, 66 withdrawn or excluded, leaving 531 (88.9%) subjects for analysis. Seroconversion to poliovirus type 1 was 10.4% for mOPV1 A, 15.6% for mOPV1 B and 10.2% for tOPV X. In trial II, 718 newborns were enrolled, 135 withdrawn or excluded, leaving 583 (81.2%) subjects for analysis. Seroconversion to poliovirus type 1 following a birth dose was 15.1%, 19.7%, 18.0% and 10.6%, following the 30-day dose 87.1%, 89.2%, 84.4%, or 55.9%, and cumulative for both doses 90.4%, 90.3%, 89.5% and 61.9% for mOPV1s B, C, and D and tOPV Y, respectively. Conclusions: In both studies, seronconversion rates were unexpectedly low to poliovirus type 1 after mOPV1 or tOPV given at birth but high for all formulations of mOPV1 given at age 30 days. The cause for low immunogenicity of OPV at birth in India is not known. © 2011 Elsevier Ltd. Source

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