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Louise B. Russell Sun-Young Kim Cristiana Toscano Ben Cosgriff Ruth Minamisava Ana Lucia Andrade Colin Sanderson Anushua Sinha 《Vaccine》2021,39(1):158-166
BackgroundThis paper compares cost-effectiveness results from two models of maternal immunization to prevent pertussis in infants in Brazil, one static, one dynamic, to explore when static models are adequate for public health decisions and when the extra effort required by dynamic models is worthwhile.MethodsWe defined two scenarios to explore key differences between static and dynamic models, herd immunity and time horizon. Scenario 1 evaluates the incremental cost/DALY of maternal acellular pertussis (aP) immunization as routine infant vaccination coverage ranges from low/moderate up to, and above, the threshold at which herd immunity begins to eliminate pertussis. Scenario 2 compares cost-effectiveness estimates over the models’ different time horizons. Maternal vaccine prices of $9.55/dose (base case) and $1/dose were evaluated.ResultsThe dynamic model shows that maternal immunization could be cost-saving as well as life-saving at low levels of infant vaccination coverage. When infant coverage reaches the threshold range (90–95%), it is expensive: the dynamic model estimates that maternal immunization costs $2 million/DALY at infant coverage > 95% and maternal vaccine price of $9.55/dose; at $1/dose, cost/DALY is $200,000. By contrast, the static model estimates costs/DALY only modestly higher at high than at low infant coverage. When the models’ estimates over their different time horizons are compared at infant coverage < 90–95%, their projections fall in the same range.ConclusionsStatic models may serve to explore an intervention’s cost-effectiveness against infectious disease: the direction and principal drivers of change were the same in both models. When, however, an intervention too small to have significant herd immunity effects itself, such as maternal aP immunization, takes place against a background of vaccination in the rest of the population, a dynamic model is crucial to accurate estimates of cost-effectiveness. This finding is particularly important in the context of widely varying routine infant vaccination rates globally.Clinical Trial registryClinical Trial registry name and registration number: Not applicable. 相似文献
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Sun-Young Kim Kyung-Duk Min Sung-mok Jung Louise B. Russell Cristiana Toscano Ruth Minamisava Ana Lucia S. Andrade Colin Sanderson Anushua Sinha 《Vaccine》2021,39(1):147-157
ObjectiveThis study evaluates the cost-effectiveness of maternal acellular pertussis (aP) immunization in low- and middle-income countries using a dynamic transmission model.MethodsWe developed a dynamic transmission model to simulate the impact of infant vaccination with whole-cell pertussis (wP) vaccine with and without maternal aP immunization. The model was calibrated to Brazilian surveillance data and then used to project health outcomes and costs under alternative strategies in Brazil, and, after adjusting model parameter values to reflect their conditions, in Nigeria and Bangladesh. The primary measure of cost-effectiveness is incremental cost (2014 USD) per disability-adjusted life-year (DALY).ResultsThe dynamic model shows that maternal aP immunization would be cost-effective in Brazil, a middle-income country, under the base-case assumptions, but would be very expensive at infant vaccination coverage in and above the threshold range necessary to eliminate the disease (90–95%). At 2007 infant coverage (DTP1 90%, DTP3 61% at 1 year of age), maternal immunization would cost < $4,000 per DALY averted. At high infant coverage, such as Brazil in 1996 (DTP1 94%, DTP3 74% at 1 year), cost/DALY increases to $1.27 million. When the model’s time horizon was extended from 2030 to 2100, cost/DALY increased under both infant coverage levels, but more steeply with high coverage. The results were moderately sensitive to discount rate, maternal vaccine price, and maternal aP coverage and were robust using the 100 best-fitting parameter sets. Scenarios representing low-income countries showed that maternal aP immunization could be cost-saving in countries with low infant coverage, such as Nigeria, but very expensive in countries, such as Bangladesh, with high infant coverage.ConclusionA dynamic model, which captures the herd immunity benefits of pertussis vaccination, shows that, in low- and middle-income countries, maternal aP immunization is cost-effective when infant vaccination coverage is moderate, even cost-saving when it is low, but not cost-effective when coverage levels pass 90–95%. 相似文献
65.
Sanjeev Gupta Sudhir Bahadur M. Mathur Aloke Thakar 《Indian journal of otolaryngology and head and neck surgery》2000,52(3):253-256
Radical neck dissection is a standard procedure carried out for the teatment of palpable nodes in the neck but if carried
out electively in cases where there are no palpable nodes in the neck it is considered to be an overtreatment with its associated
morbity. Lateral neck dissection was carried out on twenty patients who had T31 T4 lesion of the larynx and hypophar-vnx with
NO neck. The dissection entails removal of Level II. III and IV nodes. Occult metastasis 80% and 85% respectively. The mean
follow up was 13 monts. It appears from our study that elective lateral neck dissection is a promising and safe procedure
and may be useful as an important prognostic tool in sampling the lymph nodes and predicting recurrences in the neck. 相似文献
66.
We have previously isolated a drug-resistant, [PC3(R)], variant of human prostate PC3 cell line, which showed significant resistance (>10-fold) to adriamycin. No known mechanisms of drug resistance were found; however, resistant cells expressed more bcl2, c-myc, and ms oncogenes compared to the sensitive cells. In this study, we found that buthionine sulfoximine (BSO), an inhibitor of gamma-glutamyl-cysteine synthetase, decreased glutathione levels by 80-90% in both cell lines. BSO treatment down-modulated Ras protein only in PC3(R) cells and caused a 4-fold sensitization of PC3(R) cells to adriamycin without affecting PC3(W) cells. Farnesol treatment also inhibited expression of Ras protein and concomitantly reversed adriamycin resistance in PC3(R) cells, indicating that altered levels of ras expression plays an important role in drug resistance in PC3(R) cells. 相似文献
67.
The Caribbean Food and Nutrition Institute conducted a survey of anemia status of pregnant and/or lactating women in Jamaica (1982), Montserrat (1981), and St. Vincent and the Grenadines (1985). After various interventions designed to reduce the prevalence of anemia in pregnant women, follow-up surveys were conducted in the same countries five years after the initial surveys to determine whether or not the prevalence of anemia in pregnant women did indeed fall after these interventions. As of July 1984, the Jamaica Flour Mills began fortifying all baking flour and counter flour with iron (44 mg/kg) (a 70% increase in the amount of iron added), thiamine (6.3 mg/kg), riboflavin (3.9 mg/kg), and niacin (52.8 mg/kg). During the five year period following the initial survey in Montserrat, health workers had changed the type of iron administered to pregnant women, a constant supply of iron tablets was established, and the economy had improved. The changes in St. Vincent and the Grenadines were that the government provided a constant supply of iron folate (ferrous folate) tablets and there was a 1988 workshop on a manual on the control of anemia where nurses were trained in better clinic management of anemia. The prevalence of anemia (Hb 11 g/dl) in pregnant women fell from 61.6% to 53% (p 0.09) in Jamaica. It fell from 82.3% to 22.1% in Montserrat (p 0.0001). The prevalence of anemia (Hb 10 g/dl) in pregnant women fell from 25% to 14.5% (p 0.001) in St. Vincent and the Grenadines. These findings show that different interventions may have contributed to the reduction in the prevalence of anemia in pregnant women in Jamaica, Montserrat, and St. Vincent and the Grenadines. 相似文献
68.
Shrivastava SK Sharma HP Sinha SK Prasad KM 《Indian journal of pathology & microbiology》1999,42(2):169-170
We report a rare case of Retroperitonial teratoma containing Axial Skeleton long bone. Jaw, pelvis & scapula in a 27 yrs old male. Aberration in monozygotic twinning may rarely present as Fetus in Fetu. Rarer is presentation in Adult. 相似文献
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