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1.
轮状病毒是全球范围内引起婴幼儿腹泻的主要病原体,接种轮状病毒疫苗为目前最经济、有效的预防手段,很大程度上缓解了轮状病毒导致的疾病负担,但目前上市疫苗均为减毒活疫苗,存在毒力回复以及肠道不良反应等风险。因此,优化的传统活疫苗、灭活疫苗以及病毒样颗粒等亚单位疫苗成为潜在的候选疫苗,以提高轮状病毒疫苗的安全性和有效性。此文总结了市面上主要轮状病毒疫苗的应用现状以及进入临床试验新疫苗的研究情况,为后续的疫苗开发奠定基础。 相似文献
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目的评估中小学校学生流感疫苗接种效果,开展疫苗接种的卫生经济学评价,为制定流感疫苗接种策略提供依据。方法采用易感者-潜伏者-显性感染者/隐性感染者-移出者/恢复者(susceptible-exposed-infectious/asymptomatic-removed/recovered,SEIARR)动力学模型对既往疫情数据进行模拟,计算累计罹患率评估疫苗接种效果,计算成本-效果和成本-效益进行卫生经济学评价。结果当流感疫苗接种率为0%、50%、70%和90%时,疫情平均累积罹患率为99.79%(99.75%,99.82%)、70.84%(70.58%,71.09%)、56.81%(56.17%,57.45%)和34.29%(32.46%,36.20%),流感疫苗接种率越高,累计罹患率越低;当疫苗接种率为50%、70%和90%时,疫苗的成本-效果比为:141.03(139.86,142.19)元、133.16(131.34,135.08)元和112.90(110.03,116.11)元,疫苗的成本-效益比为:6.27(6.22,6.32)元、6.65(6.56,6.74)元和7.88(7.66,8.09)元;流感疫苗接种率越高,疫苗的成本-效果越好,成本-效益越高。结论接种流感疫苗能有效降低疫情的累计罹患率,提高接种率能有效增加疫苗接种的卫生经济学效应。 相似文献
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Bipul Gnyawali Antoinette Pusateri Ashley Nickerson Sajid Jalil Khalid Mumtaz 《World journal of gastroenterology : WJG》2022,28(29):3793-3802
Chronic Hepatitis B is a highly prevalent disease worldwide and is estimated to cause more than 800000 annual deaths from complications such as cirrhosis and hepatocellular carcinoma (HCC). Although universal hepatitis B vaccination programs may have reduced the incidence and prevalence of chronic hepatitis B and related HCC, the disease still imposes a significant healthcare burden in many endemic regions such as Africa and the Asia-Pacific region. This is especially concerning given the global underdiagnosis of hepatitis B and the limited availability of vaccination, screening, and treatment in low-resource regions. Demographics including male gender, older age, ethnicity, and geo graphic location as well as low socioeconomic status are more heavily impacted by chronic hepatitis B and related HCC. Methods to mitigate this impact include increasing screening in high-risk groups according to national guidelines, increasing awareness and health literacy in vulnerable populations, and developing more robust vaccination programs in under-served regions. 相似文献
5.
《Vaccine》2022,40(30):4038-4045
PurposeAs protection from COVID-19 following two doses of the BNT162b2 vaccine showed a time dependent waning, a third (booster) dose was administrated. This study aims to compare the antibody response following the third dose versus the second and to evaluate post-booster seroconversion.MethodsA prospective observational study conducted in Maccabi Healthcare Services. Serial SARS-CoV-2 Spike IgG tests, 1,2,3 and 6 months following the second vaccine dose and one month following the third were obtained. Neutralizing antibody levels were measured in a subset of participants. Per individual SARS-CoV-2 Spike IgG titer ratios were calculated one month after the booster administration compared to titers one month following the second dose and prior to booster.ResultsAmong 110 participants, 56 (51%) were women. Mean age was 61.7 ± 1.9 years and 66 (60%) were immunocompromised. One month after third dose, IgG titers were induced 7.83 (95 %CI 5.25–11.67) folds and 2.40 (95 %CI 1.90–3.03) folds compared to one month after the second, in the immunocompromised and immunocompetent groups, respectively. Of the 17 immunocompromised participants who were seronegative after the second dose, 4 (24%) became seropositive following the third. Comparing the titers prior to the third dose, an increase of 50.7 (95 %CI 32.5–79.1) fold in the immunocompromised group and 25.7 (95 %CI 19.1–34.7) fold in and immunocompetent group, was observed.ConclusionA third BNT162b2 vaccine elicited robust humoral response, superior to the response observed following the second, among immunocompetent and immunocompromised individuals. 相似文献
6.
《Vaccine》2022,40(19):2679-2695
Vaccinations are essential for preventing infectious diseases in children with chronic diseases as they have increased risk of infection from frequent use of biologics. Response to immunizations in this group is not well known.ObjectiveA systematic review was performed to evaluate three primary outcomes: efficacy; immunogenicity; and safety of vaccines in children with chronic conditions treated with biologics.MethodsThe protocol for our systematic review and meta-analysis was registered and published with PROSPERO. We searched electronic bibliographic databases for studies published from 2009 to 2019, focusing on vaccinations in children with chronic conditions treated with biologics.ResultsWe retrieved 532 records. Thirty-one full-text articles were selected, and 14 were included in the meta-analysis. No significant publication bias was found. Efficacy: limited data are available regarding the efficacy of vaccination, as most studies have focused on immunogenicity as surrogate outcome for efficacy. Immunogenicity: patients receiving anti-TNF-alpha therapy had a statistically significant risk of poor seroconversion (p = 0.028) and seroprotection by the serotype B influenza vaccine [inflammatory bowel disease (IBD) p = 0.013; juvenile idiopathic arthritis (JIA) p = 0.004]. We found adequate responses with H1N1 and H3N2 serotypes. Few studies existed for pneumococcal, hepatitis A virus, hepatitis B virus, varicella-zoster virus, Measles Mumps Rubella virus, and multiple vaccine administration. Safety: vaccine administration was not associated with serious side effects, but JIA patients on anti-TNF alpha therapy had a statistically significant risk of presenting with myalgia or arthralgia postinfluenza vaccine (p = 0.014).ConclusionsMore evidence concerning efficacy, immunogenicity, and safety of vaccinations is needed to guide physicians in the vaccine decision process for this pediatric population. 相似文献
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《Vaccine》2022,40(33):4806-4815
BackgroundThe Chinese elderly face a significant threat from seasonal influenza, owing to the consistently low vaccination coverage. This study investigated the prevalence and determinants of influenza vaccination hesitancy among the Chinese elderly.MethodsIn 2019, 3849 elderly individuals from 10 provinces in China were recruited in a cross-sectional survey. Multinomial logistic regression was applied to investigate the determinants of influenza vaccination hesitancy.ResultsAmong the elderly respondents, 37.18% expressed some degree of hesitancy towards influenza vaccination: 19.28% were hesitant, and 17.90% refused influenza vaccination, including 19.28% acceptors with doubts and 17.90% refusers. Only 39.10% of the respondents considered themselves as the priority group for influenza vaccination, and 13.93% reported receiving a recommendation for vaccination from healthcare workers. Respondents with higher education levels and from urban areas had significantly higher odds of vaccine hesitancy than their counterparts. Confidence in the safety of vaccines was negatively associated with vaccine hesitancy, but confidence in vaccine efficacy had no such association. Respondents who perceived themselves as highly susceptible to influenza (AOR = 0.85; 95 %CI = 0.77–0.93) and those aware of the elderly as a priority group for influenza vaccination (AOR = 0.51; 95 %CI = 0.41–0.64) had a significantly lower odds of being refusers.ConclusionThis study found a high prevalence of hesitancy towards influenza vaccination among the Chinese elderly, especially well-educated and urban-dwelling respondents. The government should address vaccine hesitancy through culturally appropriate communication, subsidies for vaccination, and actively promoting vaccines through primary care professionals. 相似文献
8.
目的 探究DNA聚合酶η(POLH)对过氧化氢(H2O2)诱导的晶状体上皮细胞氧化应激和凋亡的防御机制。方法 以年龄相关性白内障患者的晶状体前囊膜组织和H2O2处理的晶状体上皮细胞系SRA01/04为研究对象,分别通过RT-PCR和免疫印迹实验验证POLH的表达并筛选H2O2最佳作用浓度用于后续实验,将培养的SRA01/04细胞分为H2O2组、H2O2+HA组和H2O2+OV-POLH组,采用RT-PCR和免疫印迹实验检测POLH mRNA和蛋白表达情况,免疫荧光法检测DNA氧化损伤标志物以及TUNEL实验检测细胞凋亡变化,免疫印迹实验检测细胞中BAX、BCL-2、Nrf2和Keap1蛋白表达。结果 RT-PCR结果显示,与透明晶状体前囊膜(1.00±0.22)相比,年龄相关性白内障患者晶状体前囊膜组织中POLH mRNA相对表达量明显下降(0.38±0.62)(P<0.000 1)。RT-PCR和免疫印迹实验均显示,200 μmol·L-1 H2O2处理的SRA01/04细胞中POLH表达量最低;TUNEL实验检测结果显示, 200 μmol·L-1 H2O2处理后细胞的凋亡明显增加。RT-PCR和免疫印迹实验结果显示,与H2O2组和H2O2+HA组相比,H2O2+OV-POLH组SRA01/04细胞中POLH表达量显著升高(P<0.000 1)。免疫荧光染色结果显示,与H2O2+HA组相比,H2O2+OV-POLH组细胞的γH2A染色明显下降。免疫印迹实验检测结果显示,与H2O2组和H2O2+HA组相比,H2O2+OV-POLH组细胞促凋亡蛋白BAX表达量明显下降,而抑凋亡蛋白BCL-2表达量明显升高(均为P<0.01);与H2O2组和H2O2+HA组相比,H2O2+OV-POLH组细胞Keap1蛋白水平明显下降,而转录调控蛋白Nrf2表达明显升高(均为P<0.01)。结论 过表达POLH可通过增强DNA损伤修复功能抑制H2O2诱导的晶状体上皮细胞凋亡,其抑制氧化应激机制可能与Nrf2-Keap1-ARE通路有关。 相似文献
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《Clinical microbiology and infection》2022,28(3):410-418
ObjectiveThe dynamic adaptive immune responses elicited by the inactivated virus vaccine CoronaVac remain elusive.MethodsIn a prospective cohort of 100 healthcare professionals naïve for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) who received two doses of CoronaVac, we analysed SARS-CoV-2-specific humoral and cellular responses at four different timepoints, including before vaccination (T1), 2 weeks after the first dose (T2), 2 weeks after the booster dose (T3), and 8–10 weeks after the booster dose (T4). SARS-CoV-2-specific antibodies, serum neutralizing activities, peripheral B cells, CD4+ and CD8+ T cells and their memory subsets were simultaneously measured in this cohort.ResultsSARS-CoV-2 spike-specific IgG responses reached a peak (geometric mean titre (GMT) 54827, 30969–97065) after two doses and rapidly declined (GMT 502, 212–1190) at T4, whereas suboptimal IgA responses were detected (GMT 5, 2–9). Spike-specific circulating B cells (0.60%, 0.46–0.73% of total B cells) and memory B cells (1.18%, 0.92–1.44% of total memory B cells) were effectively induced at T3 and sustained over time (0.33%, 0.23–0.43%; 0.87%, 0.05–1.67%, respectively). SARS-CoV-2-specific circulating CD4+ T cells (0.57%, 0.47–0.66%) and CD8+ T cells (1.29%, 1.04–1.54%) were detected at T3. At T4, 0.78% (0.43–1.20%) of memory CD4+ T cells and 0.68% (0.29–1.30%) of memory CD8+ T cells were identified as SARS-CoV-2-specific, while 0.62% (0.51–0.75%) of CD4+ T cells and 0.47% (0.38–0.58%) of CD8+ T cells were SARS-CoV-2-specific terminally differentiated effector memory cells. Furthermore, age and interval between doses affected the magnitude of CoronaVac-induced immune responses. SARS-CoV-2 memory CD4+ T cells were strongly associated with both receptor binding domain (RBD)-specific memory B cells (r 0.87, p <0.0001) and SARS-CoV-2-specific memory CD8+ T cells (r 0.48, p <0.0001).ConclusionsCoronaVac induced robust circulating and memory B cell and T cell responses. Our study offers new insight into the underlying immunobiology of inactivated virus vaccines in humans and may have implications for vaccine strategies in the future. 相似文献
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