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1.
《Vaccine》2022,40(28):3851-3860
We propose a probabilistic model to quantify the cost-benefit of mass Vaccination Scenarios (VSs) against COVID-19. Through this approach, we conduct a six-month simulation, from August 31st, 2021 to March 3rd, 2022, of nine VSs, i.e., the three primary vaccine brands in Brazil (CoronaVac, AstraZeneca and Pfizer), each with three different vaccination rates (2nd doses per week). Since each vaccine has different individual-level effectiveness, we measure the population-level benefit as the probability of reaching herd immunity (HI). We quantify and categorize the cost-benefit of VSs through risk graphs that show: (i) monetary cost vs. probability of reaching HI; and (ii) number of new deaths vs. probability of reaching HI. Results show that AstraZeneca has the best cost-benefit when prioritizing acquisition costs, while Pfizer is the most cost-beneficial when prioritizing the number of deaths. This work provides helpful information that can aid public health authorities in Brazil to better plan VSs. Furthermore, our approach is not restricted to Brazil, the COVID-19 pandemic, or the mentioned vaccine brands. Indeed, the method is flexible so that this study can be a valuable reference for future cost-benefit analyses in other countries and pandemics, especially in the early stages of vaccination, when data is scarce and uncertainty is high.  相似文献   
2.
钟成望  郑婉婷  肖莎 《中国热带医学》2020,20(11):1104-1107
类鼻疽病是由类鼻疽伯克霍尔德菌(Burkholderia pseudomallei)感染引起的一类人畜共患病,主要流行于全球热带及亚热带地区。在我国主要流行于南部地区,疫源地为海南、广东、广西、台湾等。伴随着旅游业和贸易业的发展,我国其他非疫区出现了输入性病例。类鼻疽病的感染途径主要为经伤口、粘膜、呼吸道、消化道等,其病变可涉及机体所有器官,易造成较高的误诊率和病死率。然而我国目前类鼻疽病的流行病筛查技术存在一定的局限性,在防控方面未实行有效的疾病监测和疾病报告制度,对基层医师和民众疾病知识普及的力度不够。因此,本文旨在提高我国医务工作者对类鼻疽病的重视程度,从类鼻疽病的病原学特征、流行病学特征、临床特征、诊断与治疗、防控措施这五个方面进行详细综述。  相似文献   
3.
AIMS: To estimate the total prevalence of diabetes mellitus (diagnosed and undiagnosed) at national, regional and local level in England to support health-care planning and delivery. METHODS: An epidemiological model was constructed by applying age-sex-ethnic-specific reference prevalence rates from epidemiological studies to resident populations (2001 census) of England at national, regional, and local authority/Primary Care Trust levels. RESULTS: Estimated prevalence of total diabetes for all persons in England was 4.41% in 2001, equating to 2 168 000 persons. Type 2 diabetes was estimated to affect 2 002 000 persons (92.3%) and Type 1 diabetes 166 000 persons (7.7%). Diabetes prevalence was estimated to be higher in women (5.17%) than men (3.61%). People from ethnic minority groups had higher crude prevalence than White Europeans (4.29, 5.69, 6.63 and 2.13% among White Europeans, Black African/Caribbeans, South Asians and 'other' groups, respectively). Prevalence increased sharply with age (0.33, 3.37 and 13.92%, respectively, in those aged 0-29, 30-59 and 60+ years). The model allows use of user-defined population denominator estimates to derive numbers and prevalence of people with diabetes for a given local population group, such as at ward or general practice level. CONCLUSIONS: Self-reported diabetes prevalence estimates from community surveys underestimate the true burden of diabetes. The model can be used to derive the expected total prevalence of diabetes in health areas that lack reliable data to facilitate the implementation of the National Service Framework for diabetes. It will also allow estimates of future diabetes prevalence to be derived, and can potentially be used for prevalence estimates in all of the UK.  相似文献   
4.
MIC distribution data were obtained from a variety of international sources, and pooled after selection by a defined criterion. Sixty-seven of these datasets were subjected to a range of statistical goodness-of-fit tests. The log-normal distribution was selected for subsequent modelling. Cumulative counts of MIC distribution data were fitted to the cumulative log-normal distribution using non-linear least squares regression for a range of data subsets from each antibiotic-bacterium combination. Estimated parameters in the regression were the number of isolates in the subset, and (the log(2) values of) the mean and standard deviation. Optimum fits for the cumulative log-normal curve were then used to determine the wild-type MIC range, determined by calculating the MICs associated with the lower and upper 0.1% of the distribution, rounding to the nearest two-fold dilution, and calculating the probabilities of values higher and lower than these values. When plotted logarithmically, histograms of MIC frequencies appeared normal (Gaussian), but standard goodness-of-fit tests showed that the two-fold dilution grouping of MICs fits poorly to a log-normal distribution, whereas non-linear regression gave good fits to population (histogram) log-normal distributions of log(2) MIC frequencies, and even better fits to log-normal cumulative distributions. Optimum fits were found when the difference between the estimated and true number of isolates in the fitted subset was minimal. Sixteen antibiotic-bacterium datasets were fitted using this technique, and the log(2) values of the means and standard deviations were used to determine the 0.1% and 99.9% wild-type cut-off values. When rounded to the nearest two-fold dilution, > or = 98.5% of MIC values fall within the cut-off value range. Non-linear regression fitting to a cumulative log-normal distribution is a novel and effective method for modelling MIC distributions and quantifying wild-type MIC ranges.  相似文献   
5.
Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most important causative microorganisms for nosocomial infections. Recently, the incidence of isolation of MRSA has been increasing every year in Japan and is, notably, much more frequently found in inpatients than in outpatients. Therefore, we have done epidemiological studies of MRSA isolated from medical staff, inpatients, and the hospital environment in one ward of our hospital. Thereafter, we examined the antibiotic susceptibility (ABPC, DMPPC, CET, CMZ, IPM, GM, MINO, OFLX, EM, CLDM, VCM), phage typing, and coagulase typing of these MRSA. MRSA were isolated more frequently from anterior nares of inpatients than from doctors and nurses. MRSA were isolated more frequently from the environment near carriers of MRSA. Coagulase type II and phage type N.T. (not typable) were the dominant types of MRSA in our hospital (69% and 61%). MRSA strains were resistant to most antibiotics with a few exceptions (VCM, IPM, CMZ, CET). The high isolation frequency of MRSA in our hospital seems to suggest that inpatients who are carrying MRSA spread MRSA throughout the hospital environment and that the anterior nares of inpatients are the major MRSA harbor.  相似文献   
6.
HBV血清学标记携带者的传染受许多因素的影响。本研究采用多因素分析方法,定量描述了各种类型HBV血清学标记携带者家庭内传染性及有关因素影响的大小。家中上次HBsAg携带与易感者HBsAg和HBeAg阳转呈正相关。家中上次抗-HBc携带与易感者抗-HBc阳转呈正相关,OR=5.98;但与抗-HBc滴度变化无显著联系。而家中上次抗-HBc携带,HBsAg与抗-HBc同时携带与易感者HBsAg和HBeAg阳转呈负相关。年龄与HBsAg阳转呈负相关;文化水平与易感者抗-HBs阳转亦呈负相关;手术史、注射史与乙肝续发感染正相关。多因素分析对阐明人群中大量HBV血清学标记携带者的动态变化有一定意义。  相似文献   
7.
White matter lesions on computed tomography of the head were studied in relation to neuropsychological functioning in subjects from a representative sample of non-demented ( n = 134) and demented ( n = 98) 85-year-olds. Non-demented subjects with white matter lesions ( n = 46) scored significantly lower in tests of verbal ability (Synonyms), spatial ability (Block Design, Clock Test), perceptual speed (Identical forms), secondary memory (Thurstone Picture Memory), basic arithmetic (Coin Test) and the global cognitive screening test Mini-Mental State Examination than non-demented subjects without white matter lesions ( n = 88). Demented subjects with white matter lesions ( n = 67) scored significantly lower in tests of spatial ability (Block Design and Clock Test) and secondary memory (free recall in the MIR memory test, Ten-word memory test I and II) and in the Mini-Mental State Examination than demented subjects without white matter lesions ( n = 31). It is concluded that white matter lesions contribute to cognitive decline in both non-demented and demented elderly subjects.  相似文献   
8.
目的 了解绵阳市2019—2021年流行性感冒流行病学特征,为绵阳市流感防控工作提供重要依据。方法 收集绵阳市2019—2021年流感监测相关数据,采用描述性流行病学方法进行统计学分析。结果 绵阳市2019—2021年流感共报告发病55 970例,年均报告发病率388.08/10万。报告流感样病例(influenza-like illness cases, ILI) 103 723例,年平均ILI%为3.58%。2019年流感报告发病率、ILI%、阳性检出率均远超过历年同期水平。人群分类构成以15岁以下学生为主。报告发病数居前三位的地区分别为涪城区20 118例(占35.94%)、游仙区6 394例(占11.42%)、江油市5 800例(占10.36%)。2019—2021年共收到并检测ILI标本10 126份,阳性率19.53%;标本阳性检出率以15岁以下学生为主。历年流感病毒优势毒株呈现出交替流行的趋势,2019年以A(H3)型为主,2020年受新冠疫情影响,全年阳性检出率均较低,2021年除检出2份A(H9)型外,其余均为BV型。2019—2021年共报告ILI暴发疫情43起,发生时间主要集中在冬季,场所以小学居多。结论 2019—2021年绵阳市流感病例、ILI、病原学监测、暴发疫情的特征基本一致,15岁以下的学生及学校仍为重点关注人群及场所。而新型冠状病毒肺炎疫情大流行下,流感的低发水平进一步印证非药物干预措施对流感防控工作的重要性。  相似文献   
9.
The prevalence, incidence and risk factors of infectious diseases observed in the general population have been described to directly influence transfusion medicine, especially the blood selection. The objective is to ensure the blood safety. The characterization of modes of transmission influences the donor selection: the risk factors of the main blood‐borne infections have permitted to adapt the pre‐donation questionnaire in order to exclude at‐risk donors. The prevalence of infections also has an impact on the blood screening strategy. For example, anti‐HBc antibody (Ab) screening is currently performed only in countries where the HBV prevalence is compatible with a reasonable number of donor exclusions. HTLV Ab screening is implemented in countries in which the rate of donors originating from endemic areas could represent a risk for blood components. Measurement of incidence which contributes to the residual risk has led to the introduction of nucleic acid testing (NAT) for HIV, HCV and in some cases for HBV in viral screening strategy in many countries worldwide. The observed NAT yield differs according to the incidence of the infection and according to the country. Finally, the putative blood transmission of new and emerging pathogens has led to implement specific and non‐specific measures in order to enhance blood safety. Conversely, although the blood donor population is selected, the data observed in this population have also contributed to better understand epidemiology and pathogenesis of infection. Moreover, owing to the recent progress in developing modelling approaches for estimating risk, we are able to anticipate a transfusion transmission threat by introducing, when necessary, specific measures intended for reduce this risk.  相似文献   
10.
In order to describe presumed paediatric malaria on a cell-immunological basis, the soluble receptors of IL-2 (sIL-2R) and tumour necrosis factor (sTNF-R55 and sTNF-R75) were quantified in highly exposed young Tanzanian children. Sera were obtained from 66 acute and 72 reported febrile patients during health post consultations and follow-ups and from 68 community controls. Levels of sIL-2R, sTNF-R55 and sTNF-R75 were significantly elevated during fever attacks, especially in very young children. Soluble TNF-R75 levels were most stable and those of sTNF-R55 least. Levels of sTNF-R55 were related to the magnitude of fever and thus appeared to reflect attack severity. Levels of sTNF-R75 were highly significantly associated with parasite density, indicating that this response is malaria-specific. The present study indicates that sTNF-R75 levels could become a useful immunological tool in malaria intervention studies, as they reflect changes in malaria-specific immune responses. Future studies should validate this potential in different endemic settings.  相似文献   
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