关键词： poliovirus   environmental surveillance   sampling  

摘要： We performed a review of the environmental surveillance methods commonly used to collect and concentrate poliovirus (PV) from water samples. We compared the sampling approaches (trap vs grab), the process methods (precipitation vs filtration), and the various tools and chemical reagents used to separate PV from other viruses and pathogens in water samples (microporous glass, pads, polyethylene glycol [PEG]/dextran, PEG/sodium chloride, NanoCeram/ViroCap, and ester membranes). The advantages and disadvantages of each method are considered, and the geographical areas where they are currently used are discussed. Several methods have demonstrated the ability to concentrate and recover PVs from environmental samples. The details of the particular sampling conditions and locations should be considered carefully in method selection.

关键词： poliovirus   maternal antibodies   IPV   bOPV   interference   schedules  

摘要： Background. Quantifying interference of maternal antibodies with immune responses to varying dose schedules of inactivated polio vaccine (IPV) is important for the polio endgame as IPV replaces oral polio vaccine (OPV). Methods. Type 2 poliovirus humoral and intestinal responses were analyzed using pre-IPV type 2 seropositivity as proxy for maternal antibodies from 2 trials in Latin America. Infants received 1 or 2 doses of IPV in sequential IPV-bivalent oral polio vaccine (bOPV) or mixed bOPV-IPV schedules. Results. Among infants vaccinated with bOPV at age 6, 10, and 14 weeks of age and IPV at 14 weeks, those with type 2 pre-IPV seropositivity had lower seroprotection rates than seronegative infants at 4 weeks (92.7% vs 83.8%;difference, 8.9% [95% confidence interval, 0.6%-19.9%];n = 260) and 22 weeks (82.7% vs 60.4%;difference, 22.3 [12.8%-32.496];n = 481) post-IPV. A second IPV at age 36 weeks resulted in 100% seroprotection in both groups. Among infants vaccinated with 1 IPV at age 8 weeks followed by 2 doses of bOPV, pre-IPV type 2-seropositive infants had lower seroprotection at age 28 weeks than those who were seronegative (93.0% vs 73.9%;difference, 19.6% [95% confidence interval, 7.3%-29.4%];n = 168). A second dose of IPV at 16 weeks achieved >97% seroprotection at age 24 or 28 weeks, regardless of pre-IPV status. Poliovirus shedding after challenge with monovalent OPV, serotype 2, was higher in pre-IPV seropositive infants given sequential IPV-bOPV. No differences were observed in the mixed bOPV-IPV schedule. Conclusions. The presence of maternal antibody is associated with lower type 2 post-IPV seroprotection rates among infants who receive a single dose of IPV. This impact persists until late in infancy and is overcome by a second IPV dose.

关键词： OPV   HIV   VAPP   shedding   infants  

摘要： Background. Mutations associated with prolonged replication of the attenuated polioviruses found in oral poliovirus vaccine (OPV) can lead to vaccine-derived poliovirus (VDPV) and cause paralysis indistinguishable from that caused by wild poliovirus. In response, the World Health Organization has initiated the transition to exclusive use of inactivated poliovirus vaccine (IPV), with OPV administration in cases of outbreak. However, it is currently unclear how IPV-only vaccination, well known to provide humoral but not mucosal immunity, will impact the development of paralysis causing OPV variants. Children infected with human immunodeficiency virus (HIV) have been documented to show decreased mucosal immunity following OPV vaccination. Thus, HIV-infected children vaccinated with OPV may serve as proxy for children with IPV-only vaccination. Methods. We conducted a prospective study of Zimbabwean infants receiving OPV as part of their routine vaccination schedule. Stool samples collected from OPV-vaccinated children serially until age 24 months were tested for OPV serotypes using a real-time polymerase chain reaction protocol that quantifies the amount of mutant OPV variants found in each sample. Results. Out of 2130 stool samples collected from 402 infants 365 stool samples were OPV positive: 313 from 212 HIV-noninfected (HIV-) infants and 52 from 34 HIV-infected (HIV+) infants. HIV- infants showed significantly higher proportions of OPV mutants when compared to HIV+ infants. Conclusions. HIV infection is associated with a reduced proportion of OPV vaccine associated paralytic polio mutants. These results suggest that OPV administered to individuals previously vaccinated only with IPV will show decreased propensity for OPV mutations.

关键词： poliomyelitis   seroprevalence   survey   Mexico  

摘要： Background. An essential component of the "Polio Eradication and Endgame Strategic Plan 2013-2018" is the evaluation of population immunity. Mexico introduced the inactivated polio vaccine (IPV) into its routine immunization schedule in 2007 but continued to give trivalent oral polio vaccine OPV twice a year during National Health Weeks through 2016. Methods. To describe the seroprevalence of poliomyelitis among children one to four years old in Mexico and analyze risk factors for susceptibility. We detected antibodies to poliovirus type 1 by microneutralization test in 966 serum samples randomly selected from the National Health and Nutrition Survey, 2012. We assessed variables associated with susceptibility using multivariable logistic regression. Results. The overall weighted seroprevalence of the general population was 98.39% (95% confidence interval [CI] 96.76-99.21). We found significant differences of prevalence according to age (94.39%, 95% CI 87.56-97.58;99.02%, 95% CI 95.68-99.79;99.82%, 95% CI 98.77-99.98;and 100% among children 1, 2, 3, and 4 years old respectively) and number of IPV doses (96.91%, 95% CI 90.5599.44;100%;97.85%, 95% CI 94.46-99.18;and 99.92%, 95% CI 99.45-99.98 for 1 2, 3, and 4 number of doses, respectively). Multivariate analyses showed that susceptibility was associated with younger age, fewer doses of IPV, and certain socioeconomic levels. Conclusions. Overall seroprevalence was high. However, we found susceptible children among younger ages and children with fewer or unknown IPV doses belonging to certain socioeconomic strata. Results are relevant for countries transitioning from OPV to IPV and underline the importance of achieving high coverage with IPV.

关键词： Sabin   Inactivated poliovirus vaccine   IPV   sIPV   Salk   Non-human primates   Immunogenicity   Toxicity   Virus neutralizing assay  

摘要： Background: The World Health Organization recommends the development of affordable next-generation inactivated poliovirus vaccines (IPV) using attenuated poliovirus Sabin strains. Previously, we introduced a novel PER.C6 (R) cell culture platform, which allows for high yield production of an affordable trivalent Sabin IPV vaccine. Methods: Immunogenicity and safety of this novel PER.C6 (R)-based Sabin-IPV (sIPV) was assessed in rats and non-human primates (NHPs). NHPs received one of four different dose dilutions vaccine according to current human schedule (three prime-immunizations and one boost immunization). For comparison, NHPs received commercially available reference Salk IPV or sIPV. Results: Dose-dependent immunogenicity and good tolerability was observed for the PER.C6 (R)-based sIPV formulations in rats and NHPs. In NHPs, the lowest tested dose that induced anti-Sabin virus-neutralizing antibody titers that were non-inferior to commercial sIPV after three immunizations was 5-7.5-25 D-antigen units for type 1, 2 and 3 respectively. Discussion: PER.C6 (R)-based sIPV induced comparable immunogenicity to commercial Salk IPV and sIPV vaccines in NHPs. Together with the absence of any preclinical safety signals, these data warrant further testing in clinical trials. sIPV produced on the PER.C6 (R) cell platform could be one solution to the need for an affordable and immunogenic IPV to achieve and maintain global polio eradication. (C) 2018 The Author(s). Published by Elsevier Ltd.

关键词： 过氧乙酸   过氧化氢   枯草杆菌黑色变种芽孢   脊髓灰质炎病毒  

摘要： 目的比较过氧乙酸与过氧化氢混合消毒液对枯草杆菌黑色变种芽孢与脊髓灰质炎病毒杀灭效果。方法采用悬液定量杀灭试验方法,对一种过氧乙酸与过氧化氢混合消毒液杀灭细菌芽孢和病毒的效果进行了比较观察。结果用过氧乙酸浓度为1 300 mg/L、过氧化氢浓度为6 009 mg/L的消毒液作用2. 5 min,可完全杀灭悬液内枯草杆菌黑色变种芽孢。用过氧乙酸浓度为1 800 mg/L、过氧化氢浓度为8 320 mg/L的消毒液作用5. 0 min,对悬液内脊髓灰质炎病毒的灭活对数值为1. 66;作用7. 5 min,可以达到灭活病毒效果合格。结论所用消毒液灭活脊髓灰质炎病毒的剂量明显高于杀灭枯草杆菌黑色变种芽孢。

关键词： Poliomyelitis   VAPP   Poliovirus vaccine   IPV   OPV  

摘要： Objectives: Different polio vaccination schemes have been used in Russia: oral polio vaccine (OPV) was used in 1998-2007 and inactivated polio vaccine (IPV) followed by OPV in 2008-2014. This article presents the characteristics of vaccine-associated paralytic poliomyelitis (VAPP) cases in Russia during this period. Methods: VAPP cases were identified through the acute flaccid paralysis surveillance system, classified by the National Expert Classification Committee. Criteria for a 'recipient VAPP' (rVAPP) case were poliomyelitis symptoms 6-30 days a(f)ter OPV administration, isolation of the vaccine virus, and residual paralysis 60 days after disease onset. Unvaccinated cases with a similar picture 6-60 days after contact with an OPV recipient were classified as 'contact VAPP' (cVAPP) cases. Results: During 1998-2014, 127 VAPP cases were registered: 82 rVAPP and 45 cVAPP. During the period in which only OPV was used, rVAPP cases prevailed (73.8%);cases of rVAPP were reduced during the sequential scheme period (15%). Poliovirus type 3 (39.5%) and type 2 (23.7%) were isolated more often. Vaccine-derived poliovirus types 1, 2, and 3 were isolated from three cases of cVAPP. The incidence of VAPP cases was higher during the period of OPV use (1 case/1.59 million OPV doses) than during the sequential scheme period (1 case/4.18 million doses). Conclusion: The risk of VAPP exists if OPV remains in the vaccination schedule. (c) 2018 The Authors. Published by Elsevier Ltd on behalf of International Society for Infectious Diseases.

关键词： Polio vaccination   Polio dropout   Childhood immunization   Demographic and health surveys   Pakistan   Sociodemographics  

摘要： Objectives: Although the antipolio drive is undertaken across Pakistan, there are still children who have not received any oral polio vaccine or are unable to complete recommended doses of polio vaccine. This study aims at empirically analyzing the associated factors with the no oral polio vaccination (OPV) and OPV dropout groups of children in Pakistan. Study design: This is a cross-sectional study. Methods: Data were obtained from the three waves of Pakistan Demographic and Health Survey of children aged between 12 and 23 months (1990-1991: n = 1214;2006-2007: n = 1522;2012-2013: n = 2074). Children who received no OPV and those who drop out of polio vaccination (OPV1-OPV3) were considered as outcome variables. The bivariate relationship of outcome variable with each socio-economic, demographic, and spatial variable is estimated with a P-value of <0.01. For both no OPV and OPV dropout children, we used logistic regression analysis separately. Results: The percentage of children aged 12-23 months who dropped out of OPV1-OPV3 vaccination was about 76% in the year 1990-1991;21% in 2006-2007, and 17.5% in 2012-2013 at the national level. Among all indicators, provinces, rural versus urban residence, themother's age at marriage, the child's birth place (home versus hospital), parental education, and house-hold wealth status are significant predictors of no OPV and/or OPV dropout in Pakistan. Among provinces, Balochistan, Khyber Pakhtunkhwa (KPK), and Sindh are the lagging provinces. Conclusion: Improving the socio-economic status of women helps decrease the chance of polio dropout and thus improves service delivery and program implementation. (C) 2018 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

关键词： Pakistan   disease eradication   inactivated   polio   poliomyelitis   poliovirus   poliovirus vaccine   public health   vaccines   viruses  

摘要： Pakistan began using inactivated poliovirus vaccine alongside oral vaccine in mass campaigns to accelerate eradication of wild-type poliovirus in 2014. Using case-based and environmental surveillance data for January 2014-October 2017, we found that these campaigns reduced wild-type poliovirus detection more than campaigns that used only oral vaccine.

关键词： Sabin strains   Inactivated poliovirus vaccine   Phase II clinical trial   Safety   Immunogenicity  

摘要： Background: In order to completely eradicate polio caused by wild poliovirus infection as well as vaccine-associated paralytic polio (VAPP), Sabin inactivated poliovirus vaccine (sIPV) should be developed to meet the requirements for biosafety and affordable strategy in the developing countries. Method: A randomized, double-blinded clinical trial was conducted to compare the immunogenicity and safety among infants aged 2 months (60-90 days) receiving five different vaccination regimens: the test groups (A, B, and C) received three doses of sIPV with high, medium, and low D antigen content, respectively, on the month 0, 1, 2 schedule;two control groups (D and E) received three doses of conventional IPV (cIPV) or sIPV (CAMS), respectively, on the same schedule as that of test groups. Serum samples were collected immediately before the 1st dose and 30 days after the 3rd dose vaccination to assess the immunogenicity. Adverse events occurring within 30 days after each dose were collected to assess the safety. Results: After three doses, seroconversion rates in groups A-E were 100%, 98.2%, 100%, 100%, and 100%, respectively, for type 1;99.1%, 100%, 98.1%, 100%, and 97.1%, respectively, for type 2;and 100%, 100%, 100%, 100%, and 99.0%, respectively, for type 3. The seropositive rates (>= 1:8) of groups A-E for all types were nearly 100%. The GMT5 in the target dose group (group B) were 4635, 342, and 2218 for type 1-3, respectively. The most common injection-site and systemic adverse reactions were swelling and fever respectively. The swelling (4.2%, P = 0.0075) and fever (58.3%, P = 0.0188) frequency of group A were statistically significantly higher than any other groups. Conclusion: The test sIPV generally demonstrated good safety and immunogenicity. The medium-D antigen dose would be a preferred choice for the further phase III clinical trial in consideration of its high immunogenicity for all serotypes and the satisfying tolerance. (C) 2018 Elsevier Ltd. All rights re