Effect of booster doses of poliovirus vaccine in previously vaccinated children,Clinical Trial Results 2013

BackgroundConsidering the current polio situation Pakistan needs vaccine combinations to reach maximum population level immunity. The trial assessed whether inactivated poliovirus vaccine (IPV) can be used to rapidly boost immunity among children in Pakistan.MethodsA five-arm randomized clinical trial was conducted among children (6–24 months, 5–6 years and 10–11 years). Children were randomized in four intervention arms as per the vaccines they received (bOPV, IPV, bOPV + vitamin A, and bOPV + IPV) and a control arm which did not receive any vaccine. Baseline seroprevalence of poliovirus antibodies and serological immune response 28 days after intervention were assessed.ResultsThe baseline seroprevalence was high for all serotypes and the three age groups [PV1: 97%, 100%, 96%, PV2: 86%, 100%, 99%, PV3: 83%, 95%, 87% for the three age groups respectively]. There was significantly higher rate of immune response observed in the study arms which included IPV (95–99%) compared with bOPV only arms (11–43%), [p < 0.001]; Vitamin A was not associated with improved immune response. Immune response rates in the IPV only arm and IPV + bOPV arm were similar [p > 0.5].ConclusionIPV has shown the ability to efficiently close existing immunity gaps in a vulnerable population of children in rural Pakistan.     

Preparation and initial application of a monoclonal antibody specific for a newly discovered conserved linear epitope of rabies virus nucleoprotein

Objective To prepare monoclonal antibodies against a newly discovered and conserved linear epitope of Rabies virus nucleoprotein and to use them in a rabies diagnostic test.Methods Synthetic peptide containing the epitope was used as immunogen to prepare hybridoma cell lines by classical hybridoma technology.Anti-peptide monoclonal antibodies produced in ascites of inoculated Balb/c mice were labeled with fluorescein isothiocyanate (FITC) after purification and used in fluorescent antibody test (FAT). Results Two positive hybridoma cell lines,RVNP-mAb1-CL and RVNP-mAb2-CL,were obtained.RVNPmAb1-CL produced a higher concentration of monoclonal antibody RVNP-mAb1 in Balb/c ascites.FITC-labeled RVNP-mAb1 showed correct results on certain Rabies virus-positive canine brain tissue samples and cells of a small subclone of baby hamster kidney 21 cell line (BSR).Conclusion FITC-labeled RVNP-mAb1 has potential application for laboratory diagnosis of rabies.     

Immunochemical characteristics of Streptococcus pneumoniae type 3 capsular polysaccharide glycoconjugate constructs correlate with its immunogenicity in mice model

A panel of derivatives were prepared from Streptococcus pneumoniae polysaccharide type 3 (Ps3) modified with adipic acid dihydrazide (ADH). The degree of coupling between Ps3-adh derivatives and diphtheria (DTd) or tetanus (TTd) toxoids was varied by ADH linker loading. A series of Ps3 derivatives and the resultant glycoconjugates (GC) were tested for their immunochemical activity in an ELISA. Antigenic properties of components in GCs were estimated by interaction with serotype-specific and toxin-neutralizing antibodies to confirm the preservation of native protective epitopes both of Ps3 and DTd. After immunization of mice, a correlation was established between immunochemical activity and immunogenicity of these GCs. A correlation model developed for Ps3-DTd conjugates allowed to predict the immunogenicity of similar design Ps3-TTd conjugates based on ELISA testing data. The plausibility of this prediction was confirmed by the test immunization of mice with Ps3-TTds. The proposed immunochemical approach to the assessment and control of native structural and functional antigenic elements in GCs is important for the optimization of vaccine design and is an adequate alternative to extensive physicochemical characterization for assessing immunogenicity.     

我国男男性行为人群的猴痘认知现状及相关因素分析

目的了解我国MSM的猴痘知识认知现状及相关因素。方法 2022年9月5-10日在我国30个省份开展调查, 在MSM社会组织协助下, 采用方便抽样方法, 通过调查员一对一招募MSM调查对象, 由调查对象登录问卷星企业版参加线上匿名调查。样本量根据我国居民传染病防治素养水平25%进行估算。样本量估计为5 070人。采用线上自填式调查问卷, 收集社会人口学、行为学、HIV检测和猴痘有关知识认知等信息, 采用logistic回归模型分析与猴痘知识知晓的相关因素。结果 MSM调查对象为5 780人, 猴痘知识知晓率为31.8%(1 840/5 780)。多因素 logistic 回归分析结果显示, MSM猴痘知识知晓较高的相关因素包括现住址为东部地区(OR=1.26, 95%CI:1.01～1.56)、大专及以上文化程度(OR=1.50, 95%CI:1.14～1.97)、最近1个月肛交性伴数≥3人(OR=1.71, 95%CI:1.28～2.28)或2人(OR=1.36, 95%CI:1.07～1.73)、最近1个月无同性群交(OR=1.20, 95%CI:1.01～1.43)、无异性性行为(...     

Role of Diabetes Mellitus on Treatment Effects in Drug-susceptible Initial Pulmonary Tuberculosis Patients in China

We assessed the role of diabetes mellitus(DM) on treatment effects in drug‐susceptible initial pulmonary tuberculosis(PTB) patients. A prospective study was conducted in eight provinces of China from October 2008 to December 2010. We enrolled 1,313 confirmed drug‐susceptible initial PTB patients, and all subjects received the treatment regimen(2 H3 R3 E3 Z3/4 H3 R3) as recommended by the national guidelines. Of the 1,313 PTB patients, 157(11.9%) had DM; these patients had more sputum smear‐positive rates at the end of the second month [adjusted odds ratios(aO R) 2.829, 95% confidence intervals(CI) 1.783‐4.490], and higher treatment failure(aO R 2.120, 95% CI 1.565‐3.477) and death rates(aO R 1.536, 95% CI 1.011‐2.628). DM was a contributing factor for culture‐positive rates at the end of the second month and treatment failure and death of PTB patients, thus playing an unfavorable role in treatment effects of PTB.     

Clinician-parent discussions about influenza vaccination of children and their association with vaccine acceptance

ObjectiveTo examine how clinicians communicate with parents about influenza vaccination and the effect of these communication behaviors on parental vaccine decision-making.Study designWe performed a secondary analysis of data obtained from a cross-sectional observational study in which health supervision visits between pediatric clinicians and English-speaking parents of young children were videotaped. Eligible visits occurred during the 2011–2012 and 2013–2014 influenza seasons, included children ≥6 months, and contained an influenza vaccine discussion. A coding scheme of 10 communication behaviors was developed and applied to each visit. Associations between clinician communication behaviors and parental verbal vaccine acceptance and parental visit experience were examined using bivariate analysis and generalized linear mixed models.ResultsFifty visits involving 17 clinicians from 8 practices were included in analysis. The proportion of parents who accepted influenza vaccine was higher when clinicians initiated influenza vaccine recommendations using presumptive rather than participatory formats (94% vs. 28%, p < 0.001; adjusted odds ratio 48.2, 95% CI 3.5–670.5). Parental acceptance was also higher if clinicians pursued (vs. did not pursue) original recommendations when parents voiced initial resistance (80% vs. 13%, p < 0.05) or made recommendations for influenza vaccine concurrent with (vs. separate from) recommendations for other vaccines due at the visit (83% vs. 33%, p < 0.01). Parental visit experience did not differ significantly by clinician communication behaviors.ConclusionPresumptive initiation of influenza vaccine recommendations, pursuit in the face of resistance, and concurrent vaccine recommendations appear to increase parental acceptance of influenza vaccine without negatively affecting visit experience.     

Hepatitis B vaccine and the need for a booster dose after primary vaccination

ObjectivesProtective antibodies levels, induced by Hepatitis B virus (HBV) vaccine, persist for long-term after primary immunization, but there is evidence that, as the time since vaccination increases, there is a reduced ability to maintain immune memory. The study aim was to determine the prevalence and the duration of persistence of an anti-HBs titer with ≥10 mIU/mL and eventual predictors of reduced seroprotection.MethodsThe study was conducted among students attending medical and healthcare professions schools from January 2014 to June 2016. Data were collected through the review of medical records completed during the medical surveillance visit. All subjects had received HBV vaccine according to the Italian Ministry of Health indications.ResultsThe results are reported for 722 subjects. Positive anti-HBs titer was found in 72.6% (95% CI = 69–76). The mean age of the subjects was 25.5 years. Subjects vaccinated during adolescence and students that had received an adult vaccine dose were significantly more likely to be seroprotected. The longer the time interval since vaccination the lower the probability of being seroprotected; however if the role of time since vaccination was considered after stratification by vaccine dose, a statistically significant association with a lower percentage of seroprotected remains only in the subgroup of subjects who received the pediatric dose. The findings of the multivariate regression analysis partially confirmed those of the univariate analysis.ConclusionsIn conclusion, our findings show that over 25% of HBV vaccine recipients had an antiHBs titer <10 mIU/ml after 18 years of more from the primary vaccination. Furthermore, in the case a booster dose would be needed, our results suggest that the vaccination strategy should prefer administration of a vaccine adult dose during early adolescence, since it might offer longer-term protection through adulthood.     

Risk factors for measles virus infection and susceptibility in persons aged 15 years and older in China: A multi-site case-control study, 2012–2013

IntroductionEndemic measles persists in China, despite >95% reported coverage of two measles-containing vaccine doses and nationwide campaign that vaccinated >100 million children in 2010. An increasing proportion of infections now occur among adults and there is concern that persistent susceptibility in adults is an obstacle to measles elimination in China. We performed a case-control study in six Chinese provinces between January 2012 to June 2013 to identify risk factors for measles virus infection and susceptibility among adults.MethodsPersons ≥15 years old with laboratory-confirmed measles were age and neighborhood matched with three controls. Controls had blood specimens collected to determine their measles IgG serostatus. We interviewed case-patients and controls about potential risk factors for measles virus infection and susceptibility. Unadjusted and adjusted matched odds ratios and 95% confidence intervals (CIs) were calculated via conditional logistic regression. We calculated attributable fractions for infection for risk factors that could be interpreted as causal.Results899 cases and 2498 controls were enrolled. Among controls, 165 (6.6%) were seronegative for measles IgG indicating persistent susceptibility to infection. In multivariable analysis, hospital visit and travel outside the prefecture in the prior 1–3 weeks were significant risk factors for measles virus infection. Occupation and reluctance to accept measles vaccination were significant risk factors for measles susceptibility. The calculated attributable fraction of measles cases from hospital visitation was 28.6% (95% CI: 20.6–38.8%).ConclusionsExposure to a healthcare facility was the largest risk factor for measles virus infection in adults in China. Improved adherence to hospital infection control practices could reduce risk of ongoing measles virus transmission and increase the likelihood of achieving and sustaining measles elimination in China. The use of control groups stratified by serological status identified distinct risk factors for measles virus infection and susceptibility among adults.