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101.
《Vaccine》2020,38(24):3995-4000
IntroductionThe prevalence of co-infection of hepatitis B virus (HBV) and human immunodeficiency virus (HIV) is high and increases risk of hepatitis B chronicity and mortality. Despite guidelines for HIV-infected patients to be immunized against HBV, the immunogenicity of the HBV vaccination in HIV-infected patients is lower than that in the HIV-seronegative population.MethodIn this study, we performed a systematic review of the literature and meta-analysis of randomized clinical trials to investigate the response rate to an increased dose of HBV vaccination in HIV-infected patients. A fixed-effects model, with heterogeneity and sensitivity analyses, was used. We identified nine studies involving 970 HIV-positive vaccine recipients.ResultsThe study results were divided into two groups, depending on the time when antibody against hepatitis surface antigen was measured. Results showed a significant increase in response rates among patients who received a double dose of the vaccine versus the standard dose in both subgroups; the pooled odds ratio (OR) was 1.76 (95% confidence interval [CI]: 1.36–2.29) and 2.28 (95% CI: 1.73–3.01) for the rate that was measured 4–6 weeks and >12 months after completion of vaccination, respectively. The total OR was 1.99 (95% CI: 1.64–2.41). No heterogeneity was found.DiscussionOur meta-analysis shows that a double dose of the HBV vaccine may significantly improve the immune response in HIV-infected patients. Higher immunogenicity was observed, when it was measured 4–6 weeks and >12 months after completion of the vaccination.  相似文献   
102.
《Vaccine》2020,38(46):7226-7238
ObjectivesTo systematically review, appraise and evaluate available evidence regarding discrete-choice experiments (DCEs) for the human papilloma virus (HPV) vaccination in order to support policymakers in making reasonable and effective vaccination program implementation decisions.MethodsA systematic literature review was conducted using the databases PubMed and Embase for DCEs in HPV up to May 2019. Extracted data was tabulated and two checklists were used for the quality appraisal of the included studies. All attributes were categorized in outcome, process or costs attributes and the relative importance of attributes was calculated using the range method.ResultsOut of 164 identified studies, 12 met the inclusion criteria. Eight were from high income countries (HICs) and four from low and middle-income countries (LMICs). Five studies each examined vaccinee and parent preferences, while only two assessed the providers’ preferences. The studies were rather heterogenous in terms of the populations investigated, the attributes included and the methodologic approach. Overall, outcome measures were the most prominent attributes and effectiveness consistently yielded high relative importance scores. But also process factors, such as the age at vaccination, played an important role for decision making. Discrepancies between HICs and LMICs were most prominent for cost attributes.ConclusionThe heterogenous preferences this review elicited highlight the importance of context when making decisions grounded on consumer preferences. Especially the lack of evidence from LMICs, where the burden of cervical cancer is highest, is worrisome. In order to increase uptake, close vaccination gaps and reduce current inequities in (reproductive) healthcare, policy makers need to understand the features that drive individual vaccination decisions and adapt national and clinical guidelines accordingly. Future research therefore needs to focus on LMICs in order to elicit preferences of those most vulnerable populations.  相似文献   
103.
《Vaccine》2020,38(52):8343-8350
BackgroundHepatitis B virus (HBV) infection is a significant public health issue in Vietnam. Our goal was to understand the determinants of attitudes towards and practices of hepatitis B vaccine birth dose (HepB-BD) in certain regions of Vietnam.MethodA rapid qualitative assessment was conducted in three geographically diverse provinces that reported low coverage (<50%) of HepB-BD. Using purposive sampling of participants, 29 focus group discussions and 20 in-depth interviews were held with caregivers (n = 96), healthcare providers (n = 75), and healthcare administrators (n = 16). Summary notes from these were translated, and inductive coding was used to derive themes. The SAGE Vaccine Hesitancy Determinants Matrix was used as a theoretical framework to organize barriers and facilitators associated with the themes into three levels of influence.ResultsAt the individual and group level, caregivers who had higher levels of knowledge about HepB-BD sought the vaccine proactively, while others with lower knowledge faced barriers to the vaccine. Some caregivers reported a negative attitude toward health services because of a language barrier or had generalized concerns about HepB-BD due to media reporting of the past adverse events. Distress arising from potential adverse events was equally common among healthcare providers. At the contextual level, the physical environment made it difficult for caregivers to access healthcare facilities and for providers to conduct outreach. Home births posed a challenge for timely administration of HepB-BD, while health facility births facilitated it. Vaccination-specific barriers included misinterpretation of pre-vaccination screening criteria and asking for the consent of caregivers. Inadequate resources for service delivery negatively influenced HepB-BD attitudes and practices.ConclusionGiven the diversity of barriers associated with attitudes towards and practices of HepB-BD in the three provinces, tailored interventions will be necessary for both demand- and supply-side factors. Rural areas, often with more home births and geographic barriers, may require focused attention.  相似文献   
104.
Summary A large placebo-controlled efficacy trial of the rhesus tetravalent (RRV-TV) and serotype G1 monovalent (RRV-S1) rotavirus vaccines was conducted in 1991–1992 at 24 sites across the United States. Protection was 49% and 54% against all diarrhea but 80% and 69% against very severe gastroenteritis for the two vaccines, respectively. Post-vaccination neutralizing antibody titers to the G1 Wa strain, whose VP7 protein is nearly identical to that of the D strain of rotavirus contained in both vaccines, did not correlate with protection against subsequent illness with G1 strains. This result raised the possibility that in infants who developed post-vaccination neutralizing antibody to Wa, breakthrough (i.e., vaccine failure—the occurrence of rotavirus diarrhea after immunization) may have been due to infection by G1 strains that were sufficiently antigenically distinct from the vaccine strain to evade the neutralizing antibodies elicited by vaccination. To test this hypothesis, we initially compared post-vaccination neutralizing antibody titers of vaccinees against Wa and G1 breakthrough strains using sera from subjects who experienced breakthrough. Post-immunization neutralizing antibody titers to Wa elicited by vaccination were significantly (P<0.001) greater than to the breakthrough strains subsequently obtained from these subjects. This difference did not, however, correlate with lack of protection since similar differences in titer to Wa and breakthrough strains were found using post-vaccination sera from vaccinees who either experienced asymptomatic rotavirus infections or no infections. To determine the genetic basis for these differences, we compared the VP7 gene sequences of Wa with vaccine strain D, 12 G1 breakthrough strains, and 3 G1 control strains isolated during the same trial from placebo recipients. All breakthrough strains were distinct from Wa and D in antigenically important regions throughout the VP7 protein, but these differences were conserved between breakthrough and placebo strains. Furthermore, a comparative analysis of the deduced amino sequences from VP7 genes of G1 rotaviruses from 12 countries indicated that four distinct lineages have evolved. All breakthrough and control strains from the U.S. vaccine trial were in a lineage different from strain D, the serotype G1 vaccine strain. Although the overall results do not support our original hypothesis that immune selection of antigenically distinct escape mutants led to vaccine breakthrough in subjects with a neutralization response to Wa, it cannot be excluded that breakthrough could be partially due to antigenic differences in the VP7 proteins of currently circulating G1 strains.  相似文献   
105.
《Vaccine》2017,35(3):435-442
By September 2013, war between Sudan and South Sudan resulted in >70,000 Sudanese refugees and high pneumonia incidence among the 20,000 refugees in Yida camp, South Sudan. Using Médecins Sans Frontières (MSF)-provided data and modifying our decision-tree models, we estimated if administering Haemophilus influenzae type b (Hib)-containing (pentavalent vaccine, also with diphtheria pertussis and tetanus [DPT] and hepatitis B) and pneumococcal conjugate (PCV) vaccines were cost-effective against hospitalized pneumonia. Among children <2 years old, compared with no vaccination, one- and two-doses of combined Hib-containing and PCV would avert an estimated 118 and 125 pneumonia cases, and 8.5 and 9.1 deaths, respectively. The cost per Disability-Adjusted-Life-Year averted for administering combined one- and two-doses was US$125 and US$209, respectively. MSF demonstrated that it was possible to administer these vaccines during an emergency and our analysis found it was highly cost-effective, even with just one-dose of either vaccine. Despite unknown etiology, there is strong field and now economic rationale for administering Hib and PCV during at least one humanitarian emergency.  相似文献   
106.
《Vaccine》2017,35(33):4060-4063
BackgroundSeasonal influenza vaccine uptake in China is low. This study aims to assess the role of community healthcare workers (HCWs) in increasing vaccination among high risk groups in China.MethodsWe analyzed data from four knowledge, attitude and practice (KAP) studies on seasonal influenza vaccination in China targeting guardians of young children, pregnant women, adults aged ≥60 years, and HCWs from 2012 to 2014.ResultsThirty-one percent of pregnant women and 78% adults aged ≥60 years reported willingness to follow HCWs’ recommendations for influenza vaccination. Guardians were more likely to vaccinate their children if they received HCWs’ recommendations (35% vs. 17%, p < 0.001). Community HCWs were more likely to recommend seasonal influenza vaccination than hospital HCWs (58% vs. 28%, p < 0.001).ConclusionStudy results suggest the value of incorporating community HCWs’ recommendation for seasonal influenza vaccination into existing primary public health programs to increase vaccination coverage among high risk groups in China.  相似文献   
107.
108.
<正>We examined the attributed fractions of all-cause, cardiovascular, and respiratory mortality that were attributed to extreme and moderate cold and heat during 2010-2016 in Nanjing. Our results showed that 12.81%, 19.78%, and 25.33% of all-cause, cardiovascular, and respiratory mortalities, respectively, were attributed to temperature. The highest attributed fractions for three types of  相似文献   
109.
Yersinia pestis, the causative agent of bubonic and pneumonic plague, is considered to be one of the most dangerous and deadly pathogenic bacteria in the world[1]. Y. pestis? is classified as a category A pathogen by the United States Center for Disease Control and Prevention because of its ease of aerosol-to-human transmission, high lethality, and potential for mass casualties as a biological warfare agent[2]. Therefore, both prevention and treatment require the development of a rapid, sensitive, and specific?method?to?detect?Y. pestis.  相似文献   
110.
《Value in health》2023,26(6):934-942
ObjectivesThis study aimed to explore the 1-year temporal change in prevalence, variety, and potential risk factors of long COVID symptoms and to further predict the prognostic trends of long COVID.MethodsWe searched electronic databases for related studies published from January 2020 to February 2022 and conducted 1-group meta-analysis and locally weighted regression to explore the monthly temporal change in the prevalence of each long COVID symptom in 1-year follow-up period.ResultsA total of 137 studies were included in meta-analysis, including 134 093 participants. The temporal change of any long COVID symptom showed a steep decrease initially (from 92% at acute phase to 55% at 1-month follow-up), followed by stabilization at approximately 50% during 1-year follow-up. Six months or more after the acute phase, the odds ratio of population characteristic–related factors increased, such as female (from 1.62 to 1.82), whereas the odds ratio value of acute phase–related factors (severe or critical cases and hospitalization) decreased. As for specific symptoms, approximately two-thirds of the symptoms did not significantly reduce during the 1-year follow-up, and the neuropsychiatric symptoms showed a higher long-term prevalence (approximately 25%) and longer persistence than physical symptoms.ConclusionsThe temporal changes in the prevalence and characteristics speculate that long COVID may persist longer than expected. In particular, we should pay more attention to neuropsychiatric symptoms and other symptoms for which there is no significant downward trend in prevalence. The influence of acute phase–related factors for long COVID gradually decreases over time, whereas the influence of population characteristic–related factors gradually increases.  相似文献   
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