scholarly journals Comparing Vaccination Strategies in Canada Under Different Assumptions

2021 ◽  
Author(s):  
Timothy Ruse
Keyword(s):  
Single Dose ◽  
Disease Transmission ◽  
Population Level ◽  
Viral Transmission ◽  
Dose Strategy ◽  
The Third ◽  
Vaccination Strategies ◽  
Group A

ABSTRACTThis paper estimates the outcomes of two different COVID-19 vaccination strategies in Canada for the mRNA vaccines currently approved for Emergency Use Authorization (EUA), modelled on the vaccination and effectiveness of the Pfizer vaccine which is likely to be more widely administered in Canada. The first strategy is the manufacturer recommended standard of two doses (two-dose strategy) given within 21 days apart versus a strategy of giving a larger group a single dose of vaccine (first-dose-for-most strategy) by delaying the second injection.Three parameters are varied in the course of 36 estimation scenarios of the population-level effects of the two vaccination strategies. The first is the effectiveness of a single dose of vaccine at preventing disease, the second is the effectiveness of the vaccine at preventing transmission of the virus, and the third is the rate of transmission of the virus during the course of the simulations.Over the course of the different scenarios, the first-dose-for-most strategy was superior in reducing disease transmission in all scenarios where vaccination is assumed to have an effect on viral transmission. The results for fatalities was mixed, with the first-dose-for-most strategy being superior in cases where a higher first-dose effectiveness at preventing disease was assumed.Finally, in the best-guess scenarios where a 75% reduction in disease transmission and a 92.6% effectiveness at preventing disease from a single dose were used, the first-dose-for-most strategy was superior in a situation with reduced vaccine doses available, and switching to the first-dose-for-most strategy earlier helped to prevent a higher proportion of cases and deaths.

Caffeine intake reduces incident atrial fibrillation at a population level

2018 ◽  
Vol 25 (10) ◽  
pp. 1055-1062 ◽  
Author(s):  
Edoardo Casiglia ◽  
Valérie Tikhonoff ◽  
Federica Albertini ◽  
Federica Gasparotti ◽  
Alberto Mazza ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
General Population ◽  
Univariate Analysis ◽  
Population Level ◽  
Caffeine Intake ◽  
General Belief ◽  
The Third ◽  
Chronic Caffeine ◽  
Artery Disease ◽  
Cox Analysis

Background The general belief is that caffeine increases the risk of hyperkinetic arrhythmias, including atrial fibrillation. The aim of this study is to investigate the effect of chronic caffeine intake on incident atrial fibrillation in general population. Design and methods A population cohort of 1475 unselected men and women observed for 12 years and left free to intake food or beverages containing caffeine was studied. Subjects were stratified into tertiles of caffeine intake both in the whole cohort and after genotyping for the –163C > A polymorphism of the CYP1A2 gene, regulating caffeine metabolism. Results In the whole cohort, the 12-year incidence of atrial fibrillation was significantly lower in the third (2.2%) than in the first (10.2%) or second (5.7%) tertile of caffeine intake ( P < 0.001). The same trend was observed in all genotypes; the apparently steeper reduction of atrial fibrillation in slow caffeine metabolisers found at univariate analysis was proved wrong by multivariate Cox analysis. Age, chronic pulmonary disease, history of heart failure and of coronary artery disease, and systolic blood pressure − but not the genotype or the caffeine ×  CYP1A2 interaction term − were significant confounders of the association between incident atrial fibrillation and being in the third tertile of caffeine intake (hazard ratio 0.249, 95% confidence intervals 0.161–0.458, P < 0.01). Conclusions A higher caffeine intake (>165 mmol/day or > 320 mg/day) is associated with a lower incidence of atrial fibrillation in the 12-year epidemiological prospective setting based on the general population.

NOTE ON THE UNIQUENESS OF AN ENDEMIC EQUILIBRIUM OF AN EPIDEMIC MODEL WITH BOOSTING OF IMMUNITY

2021 ◽  
pp. 1-12
Author(s):  
LIU YANG ◽  
YUKIHIKO NAKATA
Keyword(s):  
Epidemic Model ◽  
Disease Transmission ◽  
Immune Status ◽  
Natural Infection ◽  
Population Level ◽  
Qualitative Property ◽  
Endemic Equilibrium ◽  
Unique Existence ◽  
Nonlinear Version ◽  
Age Dependent

For some diseases, it is recognized that immunity acquired by natural infection and vaccination subsequently wanes. As such, immunity provides temporal protection to recovered individuals from an infection. An immune period is extended owing to boosting of immunity by asymptomatic re-exposure to an infection. An individual’s immune status plays an important role in the spread of infectious diseases at the population level. We study an age-dependent epidemic model formulated as a nonlinear version of the Aron epidemic model, which incorporates boosting of immunity by a system of delay equations and study the existence of an endemic equilibrium to observe whether boosting of immunity changes the qualitative property of the existence of the equilibrium. We establish a sufficient condition related to the strength of disease transmission from subclinical and clinical infective populations, for the unique existence of an endemic equilibrium.

Transient impairment or delay of urinary trihydroxypregnanone (THS) response to metyrapone in boys with delayed adolescence and in patients with isolated growth hormone deficiency

1982 ◽  
Vol 99 (2) ◽  
pp. 166-173 ◽  
Author(s):  
M. Zachmann ◽  
D. Tassinari ◽  
W. Sorgo ◽  
G. U. Exner ◽  
B. Kempken ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Single Dose ◽  
Growth Hormone Deficiency ◽  
Bone Age ◽  
Urine Samples ◽  
Hormone Deficiency ◽  
Cortisol Response ◽  
Transient Impairment ◽  
Group A ◽  
Group B

Abstract. Twentythree boys with delayed adolescence (age 15.7 ± 2.0, bone age 12.4 ± 2.1 years) were studied. Their cortisol response to insulin was normal. After oral metyrapone (500 mg/m2 by mouth) one to three consecutive 12 h urine samples were collected for analysis of THS. Thirtyseven tests with 37 first, 21 second, and 11 third samples were carried out. The results could be divided into two main groups: 25 tests (group A) were subnormal in the first sample, 12 of them with a very weak (40 ± 8 μg/m2/12 h) and 13 with an insufficient (191 ± 16 μg/m2/12 h) THS response. Values in the second and third sample were higher, indicating a dealyed response. In 12 tests (group B), the results were normal (1016 ± 143 μg/m2/12 h) in the first and lower in the second and third samples. In three patients with repeated tests, there was improvement with increasing bone age. The THS-responses to metyrapone did not correlate with those of growth hormone, gonadotrophins, and TSH to stimuli. It is concluded that the THS-response to a single dose of metyrapone may be temporarily insufficient or delayed in delayed adolescence. We interpret this finding as showing transiently reduced or slow hypothalamic responsiveness.

scholarly journals Vaccinating Adolescents and Children Significantly Reduces COVID-19 Morbidity and Mortality across All Ages: A Popula-Tion-Based Modeling Study Using the UK as an Example

Vaccines ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 1180
Author(s):  
Tinevimbo Shiri ◽  
Marc Evans ◽  
Carla A. Talarico ◽  
Angharad R. Morgan ◽  
Maaz Mussad ◽  
...  
Keyword(s):  
Disease Transmission ◽  
Age Groups ◽  
Population Level ◽  
Vital Role ◽  
Morbidity And Mortality ◽  
Transmission Model ◽  
Base Case ◽  
Global Public Health ◽  
The Uk ◽  
The Impact

Debate persists around the risk–benefit balance of vaccinating adolescents and children against COVID-19. Central to this debate is quantifying the contribution of adolescents and children to the transmission of SARS-CoV-2, and the potential impact of vaccinating these age groups. In this study, we present a novel SEIR mathematical disease transmission model that quantifies the impact of different vaccination strategies on population-level SARS-CoV-2 infections and clinical outcomes. The model employs both age- and time-dependent social mixing patterns to capture the impact of changes in restrictions. The model was used to assess the impact of vaccinating adolescents and children on the natural history of the COVID-19 pandemic across all age groups, using the UK as an example. The base case model demonstrates significant increases in COVID-19 disease burden in the UK following a relaxation of restrictions, if vaccines are limited to those ≥18 years and vulnerable adolescents (≥12 years). Including adolescents and children in the vaccination program could reduce overall COVID-related mortality by 57%, and reduce cases of long COVID by 75%. This study demonstrates that vaccinating adolescents and children has the potential to play a vital role in reducing SARS-CoV-2 infections, and subsequent COVID-19 morbidity and mortality, across all ages. Our results have major global public health implications and provide valuable information to inform a potential pandemic exit strategy.

scholarly journals Intra-incisional versus intravenous route of antibiotic administration in preventing surgical site infections: a randomized controlled trial

2018 ◽  
Vol 5 (4) ◽  
pp. 1438
Author(s):  
Aditya N. Patil ◽  
Veerendra M. Uppin
Keyword(s):  
Single Dose ◽  
Surgical Site Infection ◽  
Tertiary Care ◽  
Surgical Site Infections ◽  
Intravenous Route ◽  
Antibiotic Administration ◽  
Site Infection ◽  
Open Appendicectomy ◽  
Group A ◽  
Group B

Background: Surgical site infection (SSI) is one of the most common postoperative complications following abdominal surgeries. Whilst the use of prophylactic antibiotics has been shown to reduce postoperative wound infection, controversy still remains as to the optimum route of administration and the duration of treatment. This study aims to compare the efficacy of a preoperative single dose of a cephalosporin antibiotic (cefotaxime) administered intraincisionally versus that administered intravenously, in preventing postoperative surgical site infections following appendicectomy.Methods: Sixty consecutive cases diagnosed as uncomplicated appendicitis who consented for open appendicectomy at a tertiary care institute were included in the study. Cases were randomized to 2 comparable groups of 30 patients each. Preoperatively, patients in Group A received a single dose of Inj. Cefotaxime 1g intraincisionally while those in Group B received the same intravenously. Incision sites were examined every alternative day starting on postoperative day 3 until removal of sutures. Signs of surgical site infection, if any, were recorded and outcomes were statistically tested for significance.Results: One patient in Group A (3.3%) and 4 patients in Group B (13.3%) showed signs of postoperative surgical site infection (p >0.05) during the follow up period which prolonged their hospital stay.Conclusions: This study showed that a single dose preoperative intraincisional administration of cefotaxime was as effective as intravenous administration for prevention of postoperative surgical site infection after open appendicectomy. Although the difference was not statistically significant, there was a reduced incidence of SSI in individuals who received intraincisional antibiotic. These results are encouraging for a way forward in reducing unnecessary burdening of systemic antibiotics in patients undergoing abdominal surgeries. 

The poet and the poison

2005 ◽  
Author(s):  
John Emsley
Keyword(s):  
Single Dose ◽  
Large Dose ◽  
Corrosive Sublimate ◽  
The Political ◽  
Good Luck ◽  
The Third ◽  
Health Authorities ◽  
Metallic Taste ◽  
Large Single Dose ◽  
To Receive

Mercury is not a particularly promising homicidal poison, but it is possible to dispose of someone by feeding them mercury(II) chloride provided you disguise its metallic taste. In the 1800s solutions of corrosive sublimate, as it was then called, were used as an antiseptic and as an insecticide against bedbugs, and its very availability resulted in thousands of poisonings being reported to the health authorities, although these were mainly accidents or as a result of its being taken deliberately in order to procure an abortion. Mercury was not a poison to feature in many murder cases because it was so easily detectable by the intended victims, especially if they started to vomit, which they almost always did. Then the metallic taste became particularly noticeable, and the presence of mercury could easily be confirmed by simple analytical tests. The poisoners who chose mercury had to use a large dose and this would kill within a day or two. Despite these inherent drawbacks, a few poisoners made use of it. Two of the murderers whose cases we are about to analyse opted for the large single dose approach, but the third murderer achieved her ends by targeting her victim with multiple doses. That murder became famous because of whom she killed and the political repercussions it caused. It was also notorious for the manner in which the final fatal dose of poison was administered. Mary Bateman was known as the Yorkshire Witch and she had a plan that she thought would lead her victims into taking a fatal single dose of mercury. Instead it led her to the gallows. At the time of her crime, Bateman lived in Leeds, Yorkshire, where she earned her living telling fortunes and swindling gullible clients out of their cash and possessions. She claimed to receive her supernatural information from a spirit medium, a Miss Blythe, into whose mouth she put the advice that always seemed to result in her clients handing over their money and saleable goods, with the promise that if they did as Miss Blythe said, then good luck would soon come their way, and they would be more than compensated.

scholarly journals Can Collagenase Be Used in the Treatment of Adhesive Capsulitis?

2019 ◽  
Vol 29 (2) ◽  
pp. 174-180
Author(s):  
Nazım Karahan ◽  
Güzelali Ozdemir ◽  
Duygu Kolukısa ◽  
Serda Duman ◽  
Fatih Arslanoğlu ◽  
...  
Keyword(s):  
Single Dose ◽  
Saline Solution ◽  
Adhesive Capsulitis ◽  
Cartilage Damage ◽  
Male Rats ◽  
Collagenase Clostridium Histolyticum ◽  
Joint Cartilage ◽  
The Third ◽  
Significant Difference ◽  
Shoulder Range

Background: The objective of this study was to evaluate the efficacy of subacromial injections of collagenase and corticosteroid in rats with experimentally induced adhesive capsulitis. Method: Thirty adult Wistar albino male rats were distributed into 3 groups of 10 rats each after stabilization of their shoulders for 3 weeks: the first group received a single dose of 0.002 mg (0.25 mL) subacromial collagenase; the second group received a single dose of 1.60 mg (0.25 mL) subacromial steroid, and the third group received a single dose of 0.25 mL subacromial saline solution. One week later, we investigated shoulder range of motions, collagen content of the shoulder, and joint cartilage structure. Results: There was no statistically significant difference in the cartilage damage between the groups (p > 0.05). Fibrosis measurements were significantly lower in the collagenase group than in the steroid and saline groups. There was no significant difference in fibrosis between the steroid and saline groups (p > 0.05). Abduction measurements were significantly higher in the collagenase group than in the steroid and saline groups (p < 0.001). No significant difference in the abduction measurements was observed between the saline and steroid groups (p > 0.05). Conclusion: We observed that subacromial injections of collagenase Clostridium histolyticum effectively treated adhesive capsulitis. The results suggest that this treatment could be considered for use in patients with an intact rotator cuff.

Inverse semigroups generated by a pair of subgroups

1977 ◽  
Vol 77 (1-2) ◽  
pp. 9-22 ◽  
Author(s):  
D. B. McAlister
Keyword(s):  
Inverse Semigroup ◽  
Free Product ◽  
Homomorphic Image ◽  
Main Part ◽  
Structure Theorem ◽  
Inverse Semigroups ◽  
Infinite Cyclic Group ◽  
The Third ◽  
Group A ◽  
Maximum Group

SynopsisThe aim of this paper is to describe the free product of a pair G, H of groups in the category of inverse semigroups. Since any inverse semigroup generated by G and H is a homomorphic image of this semigroup, this paper can be regarded as asking how large a subcategory, of the category of inverse semigroups, is the category of groups? In this light, we show that every countable inverse semigroup is a homomorphic image of an inverse subsemigroup of the free product of two copies of the infinite cyclic group. A similar result can be obtained for arbitrary cardinalities. Hence, the category of inverse semigroups is generated, using algebraic constructions by the subcategory of groups.The main part of the paper is concerned with obtaining the structure of the free product G inv H, of two groups G, H in the category of inverse semigroups. It is shown in section 1 that G inv H is E-unitary; thus G inv H can be described in terms of its maximum group homomorphic image G gp H, the free product of G and H in the category of groups, and its semilattice of idempotents. The second section considers some properties of the semilattice of idempotents while the third applies these to obtain a representation of G inv H which is faithful except when one group is a non-trivial finite group and the other is trivial. This representation is used in section 4 to give a structure theorem for G inv H. In this section, too, the result described in the first paragraph is proved. The last section, section 5, consists of examples.

Age-related changes in erythrocyte agglutinability in Hiroshima subjects

1961 ◽  
Vol 16 (6) ◽  
pp. 1093-1096
Author(s):  
J. W. Hollingsworth ◽  
H. B. Hamilton ◽  
G. Ishii
Keyword(s):  
Blood Group ◽  
Technical Assistance ◽  
Atomic Bomb ◽  
Accelerated Aging ◽  
The Third ◽  
Age Related ◽  
Group A ◽  
Age Related Changes

As part of a physiologic aging assessment in survivors of the atomic bombing, agglutinability of erythrocytes with A and B antisera was studied in 1,495 subjects in Hiroshima. It was found that erythrocyte agglutinability is maximal during the third decade and falls progressively with advancing years. At age 20—40, agglutinability of erythrocytes from females was somewhat less than that of males. Subjects of blood group AB demonstrated agglutinability titers with both antisera comparable to the titers of the group A and B subjects. Analysis of agglutinability titers in relationship to degree of irradiation from the Hiroshima atomic bomb in 1945 failed to show differences, but the sample was too small to allow definite conclusions about possible radiation-accelerated aging. Note: With the Technical Assistance of N. Ueda Submitted on February 16, 1961

Carbamazepine Phakmacokinetics in Obese and Lean Subjects

1995 ◽  
Vol 29 (9) ◽  
pp. 843-847 ◽  
Author(s):  
Yoseph Caraco ◽  
Ester Zylber-Katz ◽  
Elliot M Berry ◽  
Micha Levy
Keyword(s):  
Body Weight ◽  
Single Dose ◽  
Ideal Body Weight ◽  
Obese Group ◽  
University Hospital ◽  
Pharmacokinetic Parameters ◽  
Group A ◽  
Obese Subjects ◽  
Group B ◽  
Lean Group

Objective: To compare carbamazepine pharmacokinetic parameters between obese and lean subjects following the administration of a single 200-mg tablet. Design: Single-dose intervention, open study. Setting: Teaching university hospital. Subjects: Eighteen obese (group A) otherwise healthy subjects, referred to the metabolic outpatient clinic, and 13 healthy lean (group B) volunteers. Inclusion criterion for the obese subjects was a body mass index (BMI = weight/height2) of more than 30 kg/m2. In the obese group, mean ± SD total body weight (TBW), BMI, and percent of ideal body weight (IBW) were 111.4 ± 19.9 kg, 38.8 ± 6.0 kg/m2, and 182.7% ± 30.7%, respectively. These values were significantly greater than the respective values of 63.2 ± 8.3 kg, 22.4 ± 1.6 kg/m2, and 105.8% ± 5.8% obtained in the lean group (p < 0.001). Intervention: Single-dose oral administration of carbamazepine 200-mg tablet (Teril, Taro, Israel). Outcomes: Carbamazepine elimination half-life (t1/2), apparent volume of distribution (Varea/F), and its oral clearance (Clpo/F) were derived from the drug concentration-time curves. Results: Carbamazepine Varea/F and t1/2 were significantly greater in group A than in group B (98.4 ± 26.9 vs. 60.7 ± 8.5 L, respectively, p < 0.001; and 59.4 ± 14.7 vs. 31.0 ± 5.0 h, respectively, p < 0.001), but its Clpo/F was reduced only slightly in obese as compared with lean subjects (19.8 ± 5.2 vs. 23.0 ± 4.6 mL/min, respectively, p = 0.07). Correction for IBW yielded similar results for Varea/F and t1/2, but Clpo/F per kg of IBW was significantly smaller in the obese than in the lean subjects (0.32 ± 0.07 vs. 0.39 ± 0.06 mL/min/kg of IBW, respectively, p < 0.02). Linear correlations were observed between Varea/F and TBW for both group A (r = 0.92, p < 0.001) and group B (r = 0.77, p < 0.002). Conclusions: In comparison with lean subjects, carbamazepine Varea/F is significantly greater in obese subjects and its t1/2 is markedly prolonged. The minor nonsignificant effect of obesity on carbamazepine Clpo/F suggests that in obese subjects the carbamazepine daily dose should be based on IBW, not on TBW.

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