Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 86
Filtrar
1.
Lancet Planet Health ; 4(7): e280-e291, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32681899

RESUMEN

BACKGROUND: Agrochemical pollution of surface waters is a growing global environmental challenge, especially in areas where agriculture is rapidly expanding and intensifying. Agrochemicals might affect schistosomiasis transmission through direct and indirect effects on Schistosoma parasites, their intermediate snail hosts, snail predators, and snail algal resources. We aimed to review and summarise the effects of these agrochemicals on schistosomiasis transmission dynamics. METHODS: We did a systematic review of agrochemical effects on the lifecycle of Schistosoma spp and fitted dose-response models to data regarding the association between components of the lifecycle and agrochemical concentrations. We incorporated these dose-response functions and environmentally relevant concentrations of agrochemicals into a mathematical model to estimate agrochemical effects on schistosomiasis transmission. Dose-response functions were used to estimate individual agrochemical effects on estimates of the agrochemically influenced basic reproduction number, R0, for Schistosoma haematobium. We incorporated time series of environmentally relevant agrochemical concentrations into the model and simulated mass drug administration control efforts in the presence of agrochemicals. FINDINGS: We derived 120 dose-response functions describing the effects of agrochemicals on schistosome lifecycle components. The median estimate of the basic reproduction number under agrochemical-free conditions, was 1·65 (IQR 1·47-1·79). Agrochemical effects on estimates of R0 for S haematobium ranged from a median three-times increase (R0 5·05, IQR 4·06-5·97) to transmission elimination (R0 0). Simulations of transmission dynamics subject to interacting annual mass drug administration and agrochemical pollution yielded a median estimate of 64·82 disability-adjusted life-years (DALYs) lost per 100 000 people per year (IQR 62·52-67·68) attributable to atrazine use. In areas where aquatic arthropod predators of intermediate host snails suppress transmission, the insecticides chlorpyrifos (6·82 DALYs lost per 100 000 people per year, IQR 4·13-8·69) and profenofos (103·06 DALYs lost per 100 000 people per year, IQR 89·63-104·90) might also increase the disability burden through their toxic effects on arthropods. INTERPRETATION: Expected environmental concentrations of agrochemicals alter schistosomiasis transmission through direct and indirect effects on intermediate host and parasite densities. As industrial agricultural practices expand in areas where schistosomiasis is endemic, strategies to prevent increases in transmission due to agrochemical pollution should be developed and pursued. FUNDING: National Science Foundation, National Institutes of Health.

2.
J Infect Dis ; 221(Supplement_1): S86-S93, 2020 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-32134475

RESUMEN

BACKGROUND: Several cytomegalovirus (CMV) vaccine candidates are under development. To reduce the burden of congenital CMV infection, potential strategies under consideration include vaccination of adult women, adolescent girls, and/or young children (both sexes). METHODS: We reviewed 5 studies that used infectious disease modeling to assess the potential impact of vaccination for preventing congenital CMV infection. All models assumed CMV vaccination would prevent primary infection and 2 models also assumed prevention of reinfections and reactivations. RESULTS: Despite differences in structure, assumptions, and population data, infant vaccination (both sexes) was the optimal strategy in all models, but in 1 model vaccinating seronegative women at 19-21 years of age was also optimal (for duration of vaccine protection ≥8 years). In 3 models, infant vaccination increased average age at primary infection as a result of decreased secondary transmission (herd immunity) combined with waning vaccine-induced immunity. This effect could increase the risk of congenital CMV infections in populations where primary CMV infection occurs early in childhood but could be minimized by administering a second dose of vaccine during adolescence. CONCLUSIONS: Understanding vaccine efficacy and duration of immunity, and how these might vary depending on CMV serostatus and age at vaccination, will be key to defining CMV vaccination strategies.

3.
JAMA Pediatr ; 2019 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-31738391

RESUMEN

Importance: Measles cases and outbreaks continue to occur in the United States after the introduction of measles from endemic settings. Objective: To discern the factors associated with measles transmission in the United States after measles had been eliminated. Design, Setting, and Participants: This cross-sectional study was conducted from January 1, 2001, to December 31, 2017, in the United States among US residents and international visitors with confirmed measles. A maximum likelihood algorithm that uses the observed dates of rash onset and the known distribution of the serial interval (time between symptom onset in related consecutive cases) was applied to outbreak notification data to estimate the effective reproduction number (R), or the mean number of new infections generated per case. Transmissibility was assessed by comparing R based on the characteristics of primary and secondary cases of measles. Exposures: Measles virus. Main Outcomes and Measures: Effective reproduction number (R), or the mean number of successful transmission events per case of measles (ie, the mean number of persons to whom each patient with measles spreads measles). Results: A total of 2218 individuals with confirmed measles cases (1025 female, 1176 male, and 17 sex not reported; median age, 15 years [range, 0-89 years]) reported from 2001 to 2017 were evaluated. Among patients who received no doses of measles vaccine, R was 0.76 (95% CI, 0.71-0.81); among patients who received 1 dose of measles vaccine, R was 0.17 (95% CI, 0.11-0.26); among patients who received 2 doses or more of measles vaccine, R was 0.27 (95% CI, 0.17-0.39); and among patients with unknown vaccination status, R was 0.52 (95% CI, 0.44-0.60). Among patients born before 1957, R was 0.35 (95% CI, 0.20-0.58), and among those born on or after 1957, R was 0.64 (95% CI, 0.61-0.68). R was higher when primary and secondary cases of measles were patients aged 5 to 17 years (0.36 [95% CI, 0.31-0.42]) compared with assortative transmission in other age groups (<1 year, 0.14 [95% CI, 0.10-0.20]; 1-4 years, 0.25 [95% CI, 0.20-0.30]; 18-29 years, 0.19 [95% CI, 0.15-0.24]; 30-49 years, 0.15 [95% CI, 0.11-0.20]; ≥50 years, 0.04 [95% CI, 0.01-0.10]). Conclusions and Relevance: The findings of this study support having high targets for 2-dose measles vaccine coverage, particularly among school-aged children in the United States.

4.
Epidemiol Rev ; 41(1): 34-50, 2019 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-31781750

RESUMEN

In 2014-2015, a large Ebola outbreak afflicted Liberia, Guinea, and Sierra Leone. We performed a systematic review of 26 manuscripts, published between 2014 and April 2015, that forecasted the West African Ebola outbreak while it was occurring, and we derived implications for how results could be interpreted by policymakers. Forecasted case counts varied widely. An important determinant of forecast accuracy for case counts was how far into the future predictions were made. Generally, forecasts for less than 2 months into the future tended to be more accurate than those made for more than 10 weeks into the future. The exceptions were parsimonious statistical models in which the decay of the rate of spread of the pathogen among susceptible individuals was dealt with explicitly. The most important lessons for policymakers regarding future outbreaks, when using similar modeling results, are: 1) uncertainty of forecasts will be greater in the beginning of the outbreak; 2) when data are limited, forecasts produced by models designed to inform specific decisions should be used complementarily for robust decision-making (e.g., 2 statistical models produced the most reliable case-counts forecasts for the studied Ebola outbreak but did not enable understanding of interventions' impact, whereas several compartmental models could estimate interventions' impact but required unavailable data); and 3) timely collection of essential data is necessary for optimal model use.

5.
Epidemics ; 28: 100348, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31235334

RESUMEN

We used individual-based computer simulation models at community, regional and national levels to evaluate the likely impact of coordinated pre-emptive school dismissal policies during an influenza pandemic. Such policies involve three key decisions: when, over what geographical scale, and how long to keep schools closed. Our evaluation includes uncertainty and sensitivity analyses, as well as model output uncertainties arising from variability in serial intervals and presumed modifications of social contacts during school dismissal periods. During the period before vaccines become widely available, school dismissals are particularly effective in delaying the epidemic peak, typically by 4-6 days for each additional week of dismissal. Assuming the surveillance is able to correctly and promptly diagnose at least 5-10% of symptomatic individuals within the jurisdiction, dismissals at the city or county level yield the greatest reduction in disease incidence for a given dismissal duration for all but the most severe pandemic scenarios considered here. Broader (multi-county) dismissals should be considered for the most severe and fast-spreading (1918-like) pandemics, in which multi-month closures may be necessary to delay the epidemic peak sufficiently to allow for vaccines to be implemented.

6.
BMC Infect Dis ; 19(1): 244, 2019 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-30866840

RESUMEN

BACKGROUND: In current epidemiology of tuberculosis (TB), heterogeneity in infectiousness among TB patients is a challenge, which is not well studied. We aimed to quantify this heterogeneity and the presence of "super-spreading" events that can assist in designing optimal public health interventions. METHODS: TB epidemiologic investigation data notified between 1 January 2005 and 31 December 2015 from Victoria, Australia were used to quantify TB patients' heterogeneity in infectiousness and super-spreading events. We fitted a negative binomial offspring distribution (NBD) for the number of secondary infections and secondary active TB disease each TB patient produced. The dispersion parameter, k, of the NBD measures the level of heterogeneity, where low values of k (e.g. k < 1) indicate over-dispersion. Super-spreading was defined as patients causing as many or more secondary infections as the 99th centile of an equivalent homogeneous distribution. Contact infection was determined based on a tuberculin skin test (TST) result of ≥10 mm. A NBD model was fitted to identify index characteristics that were associated with the number of contacts infected and risk ratios (RRs) were used to quantify the strength of this association. RESULTS: There were 4190 (2312 pulmonary and 1878 extrapulmonary) index TB patients and 18,030 contacts. A total of 15,522 contacts were tested with TST, of whom 3213 had a result of ≥10 mm. The dispersion parameter, k for secondary infections was estimated at 0.16 (95%CI 0.14-0.17) and there were 414 (9.9%) super-spreading events. From the 3213 secondary infections, 2415 (75.2%) were due to super-spreading events. There were 226 contacts who developed active TB disease and a higher level of heterogeneity was found for this outcome than for secondary infection, with k estimated at 0.036 (95%CI 0.025-0.046). In regression analyses, we found that infectiousness was greater among index patients found by clinical presentation and those with bacteriological confirmation. CONCLUSION: TB transmission is highly over dispersed and super-spreading events are responsible for a substantial majority of secondary infections. Heterogeneity of transmission and super-spreading are critical issues to consider in the design of interventions and models of TB transmission dynamics.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Trazado de Contacto , Humanos , Estudios Retrospectivos , Tuberculosis/epidemiología , Tuberculosis/transmisión , Victoria/epidemiología
7.
PLoS One ; 13(12): e0208203, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30521550

RESUMEN

BACKGROUND: Dengue is the fastest spreading vector-borne viral disease, resulting in an estimated 390 million infections annually. Precise prediction of many attributes related to dengue is still a challenge due to the complex dynamics of the disease. Important attributes to predict include: the risk of and risk factors for an infection; infection severity; and the timing and magnitude of outbreaks. In this work, we build a model for predicting the risk of dengue transmission using high-resolution weather data. The level of dengue transmission risk depends on the vector density, hence we predict risk via vector prediction. METHODS AND FINDINGS: We make use of surveillance data on Aedes aegypti larvae collected by the Taiwan Centers for Disease Control as part of the national routine entomological surveillance of dengue, and weather data simulated using the IBM's Containerized Forecasting Workflow, a high spatial- and temporal-resolution forecasting system. We propose a two stage risk prediction system for assessing dengue transmission via Aedes aegypti mosquitoes. In stage one, we perform a logistic regression to determine whether larvae are present or absent at the locations of interest using weather attributes as the explanatory variables. The results are then aggregated to an administrative division, with presence in the division determined by a threshold percentage of larvae positive locations resulting from a bootstrap approach. In stage two, larvae counts are estimated for the predicted larvae positive divisions from stage one, using a zero-inflated negative binomial model. This model identifies the larvae positive locations with 71% accuracy and predicts the larvae numbers producing a coverage probability of 98% over 95% nominal prediction intervals. This two-stage model improves the overall accuracy of identifying larvae positive locations by 29%, and the mean squared error of predicted larvae numbers by 9.6%, against a single-stage approach which uses a zero-inflated binomial regression approach. CONCLUSIONS: We demonstrate a risk prediction system using high resolution weather data can provide valuable insight to the distribution of risk over a geographical region. The work also shows that a two-stage approach is beneficial in predicting risk in non-homogeneous regions, where the risk is localised.


Asunto(s)
Virus del Dengue/patogenicidad , Dengue/transmisión , Brotes de Enfermedades/prevención & control , Modelos Biológicos , Mosquitos Vectores/virología , Aedes/virología , Animales , Dengue/epidemiología , Dengue/virología , Monitoreo del Ambiente/estadística & datos numéricos , Humanos , Larva/virología , Modelos Logísticos , Densidad de Población , Medición de Riesgo/métodos , Taiwán/epidemiología , Tiempo (Meteorología)
8.
PLoS Negl Trop Dis ; 12(11): e0006794, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30418968

RESUMEN

Progress towards controlling and eliminating parasitic worms, including schistosomiasis, onchocerciasis, and lymphatic filariasis, is advancing rapidly as national governments, multinational NGOs, and pharmaceutical companies launch collaborative chemotherapeutic control campaigns. Critical questions remain regarding the potential for achieving elimination of these infections, and analytical methods can help to quickly estimate progress towards-and the probability of achieving-elimination over specific timeframes. Here, we propose the effective reproduction number, Reff, as a proxy of elimination potential for sexually reproducing worms that are subject to poor mating success at very low abundance (positive density dependence, or Allee effects). Reff is the number of parasites produced by a single reproductive parasite at a given stage in the transmission cycle, over the parasite's lifetime-it is the generalized form of the more familiar basic reproduction number, R0, which only applies at the beginning of an epidemic-and it can be estimated in a 'model-free' manner by an estimator ('ε'). We introduce ε, demonstrate its estimation using simulated data, and discuss how it may be used in planning and evaluation of ongoing elimination efforts for a range of parasitic diseases.


Asunto(s)
Erradicación de la Enfermedad/métodos , Administración Masiva de Medicamentos/estadística & datos numéricos , Schistosoma/efectos de los fármacos , Esquistosomiasis/epidemiología , Esquistosomiasis/prevención & control , Animales , Número Básico de Reproducción , Recolección de Datos , Erradicación de la Enfermedad/estadística & datos numéricos , Métodos Epidemiológicos , Humanos , Administración Masiva de Medicamentos/métodos , Modelos Teóricos , Oncocercosis/tratamiento farmacológico , Parásitos/fisiología , Enfermedades Parasitarias/tratamiento farmacológico , Enfermedades Parasitarias/epidemiología , Enfermedades Parasitarias/parasitología , Reproducción , Schistosoma/fisiología , Esquistosomiasis/tratamiento farmacológico , Esquistosomiasis/transmisión
9.
Malar J ; 17(1): 299, 2018 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-30119664

RESUMEN

BACKGROUND: Much of the extensive research regarding transmission of malaria is underpinned by mathematical modelling. Compartmental models, which focus on interactions and transitions between population strata, have been a mainstay of such modelling for more than a century. However, modellers are increasingly adopting agent-based approaches, which model hosts, vectors and/or their interactions on an individual level. One reason for the increasing popularity of such models is their potential to provide enhanced realism by allowing system-level behaviours to emerge as a consequence of accumulated individual-level interactions, as occurs in real populations. METHODS: A systematic review of 90 articles published between 1998 and May 2018 was performed, characterizing agent-based models (ABMs) relevant to malaria transmission. The review provides an overview of approaches used to date, determines the advantages of these approaches, and proposes ideas for progressing the field. RESULTS: The rationale for ABM use over other modelling approaches centres around three points: the need to accurately represent increased stochasticity in low-transmission settings; the benefits of high-resolution spatial simulations; and heterogeneities in drug and vaccine efficacies due to individual patient characteristics. The success of these approaches provides avenues for further exploration of agent-based techniques for modelling malaria transmission. Potential extensions include varying elimination strategies across spatial landscapes, extending the size of spatial models, incorporating human movement dynamics, and developing increasingly comprehensive parameter estimation and optimization techniques. CONCLUSION: Collectively, the literature covers an extensive array of topics, including the full spectrum of transmission and intervention regimes. Bringing these elements together under a common framework may enhance knowledge of, and guide policies towards, malaria elimination. However, because of the diversity of available models, endorsing a standardized approach to ABM implementation may not be possible. Instead it is recommended that model frameworks be contextually appropriate and sufficiently described. One key recommendation is to develop enhanced parameter estimation and optimization techniques. Extensions of current techniques will provide the robust results required to enhance current elimination efforts.


Asunto(s)
Transmisión de Enfermedad Infecciosa , Interacciones Huésped-Parásitos , Malaria/transmisión , Modelos Estadísticos , Mosquitos Vectores/fisiología , Animales , Humanos
10.
Pathog Glob Health ; 112(4): 195-202, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29874978

RESUMEN

Epidemiological studies have identified an increased risk of diarrheal diseases associated with using shared sanitation facilities. We hypothesized that this might be related to differences in transmission routes of pathogens. We proposed a mathematical model of two fictitious pathogens, one transmitted with an environmental reservoir and one without. We assumed that individuals susceptible to one pathogen are not susceptible to the other, and therefore, decoupled the two models. We initialized the model with 99% individuals being susceptible. We sampled the parameter space using Latin Hypercube Sampling. We simulated 10,000 parameter sets. We varied the effective shared sanitation coverage (the product of latrine coverage and users' compliance). Our results show that, in our hypothetical scenario, across all levels of effective coverage of shared sanitation, the median final cumulative incidence of diarrheal disease was higher than that of zero coverage. Our simulation findings suggest that increasing effective coverage of shared sanitation may have limited benefits against diarrhea-causing pathogens with an environmental reservoir and may lack benefit against diarrhea-causing pathogens without an environmental reservoir given increased human contacts if latrines are poorly maintained.


Asunto(s)
Diarrea/epidemiología , Transmisión de Enfermedad Infecciosa , Modelos Teóricos , Saneamiento/métodos , Cuartos de Baño , Humanos , Incidencia
12.
PLoS Negl Trop Dis ; 12(5): e0006490, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29791440

RESUMEN

BACKGROUND: Dog rabies annually causes 24,000-70,000 deaths globally. We built a spreadsheet tool, RabiesEcon, to aid public health officials to estimate the cost-effectiveness of dog rabies vaccination programs in East Africa. METHODS: RabiesEcon uses a mathematical model of dog-dog and dog-human rabies transmission to estimate dog rabies cases averted, the cost per human rabies death averted and cost per year of life gained (YLG) due to dog vaccination programs (US 2015 dollars). We used an East African human population of 1 million (approximately 2/3 living in urban setting, 1/3 rural). We considered, using data from the literature, three vaccination options; no vaccination, annual vaccination of 50% of dogs and 20% of dogs vaccinated semi-annually. We assessed 2 transmission scenarios: low (1.2 dogs infected per infectious dog) and high (1.7 dogs infected). We also examined the impact of annually vaccinating 70% of all dogs (World Health Organization recommendation for dog rabies elimination). RESULTS: Without dog vaccination, over 10 years there would a total of be approximately 44,000-65,000 rabid dogs and 2,100-2,900 human deaths. Annually vaccinating 50% of dogs results in 10-year reductions of 97% and 75% in rabid dogs (low and high transmissions scenarios, respectively), approximately 2,000-1,600 human deaths averted, and an undiscounted cost-effectiveness of $451-$385 per life saved. Semi-annual vaccination of 20% of dogs results in in 10-year reductions of 94% and 78% in rabid dogs, and approximately 2,000-1,900 human deaths averted, and cost $404-$305 per life saved. In the low transmission scenario, vaccinating either 50% or 70% of dogs eliminated dog rabies. Results were most sensitive to dog birth rate and the initial rate of dog-to-dog transmission (Ro). CONCLUSIONS: Dog rabies vaccination programs can control, and potentially eliminate, dog rabies. The frequency and coverage of vaccination programs, along with the level of dog rabies transmission, can affect the cost-effectiveness of such programs. RabiesEcon can aid both the planning and assessment of dog rabies vaccination programs.


Asunto(s)
Enfermedades de los Perros/economía , Enfermedades de los Perros/prevención & control , Programas de Inmunización/economía , Vacunas Antirrábicas/economía , Rabia/prevención & control , Vacunación/economía , África Oriental , Animales , Análisis Costo-Beneficio , Enfermedades de los Perros/mortalidad , Enfermedades de los Perros/transmisión , Perros , Femenino , Humanos , Programas de Inmunización/métodos , Masculino , Modelos Teóricos , Rabia/economía , Rabia/mortalidad , Rabia/transmisión , Vacunas Antirrábicas/administración & dosificación
13.
Nat Commun ; 9(1): 837, 2018 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-29483531

RESUMEN

Schistosomiasis is a snail-borne parasitic disease that ranks among the most important water-based diseases of humans in developing countries. Increased prevalence and spread of human schistosomiasis to non-endemic areas has been consistently linked with water resource management related to agricultural expansion. However, the role of agrochemical pollution in human schistosome transmission remains unexplored, despite strong evidence of agrochemicals increasing snail-borne diseases of wildlife and a projected 2- to 5-fold increase in global agrochemical use by 2050. Using a field mesocosm experiment, we show that environmentally relevant concentrations of fertilizer, a herbicide, and an insecticide, individually and as mixtures, increase densities of schistosome-infected snails by increasing the algae snails eat and decreasing densities of snail predators. Epidemiological models indicate that these agrochemical effects can increase transmission of schistosomes. Identifying agricultural practices or agrochemicals that minimize disease risk will be critical to meeting growing food demands while improving human wellbeing.


Asunto(s)
Agroquímicos/farmacología , Astacoidea/efectos de los fármacos , Heterópteros/efectos de los fármacos , Schistosoma haematobium/efectos de los fármacos , Schistosoma mansoni/efectos de los fármacos , Esquistosomiasis/veterinaria , Caracoles/efectos de los fármacos , Animales , Astacoidea/fisiología , Atrazina/farmacología , Cloropirifos/farmacología , Cricetinae , Ecosistema , Fertilizantes/toxicidad , Cadena Alimentaria , Heterópteros/fisiología , Humanos , Recuento de Huevos de Parásitos , Perifiton/efectos de los fármacos , Perifiton/fisiología , Fitoplancton/efectos de los fármacos , Fitoplancton/crecimiento & desarrollo , Estanques , Riesgo , Schistosoma haematobium/crecimiento & desarrollo , Schistosoma mansoni/crecimiento & desarrollo , Esquistosomiasis/parasitología , Esquistosomiasis/transmisión , Caracoles/parasitología
14.
J Gerontol A Biol Sci Med Sci ; 73(6): 798-805, 2018 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-29360935

RESUMEN

Background: Older individuals (aged ≥65 years) are commonly prescribed statins but may experience a range of barriers in adhering to therapy. The factors associated with poor statin adherence and/or discontinuation among this population have not been comprehensively reviewed. Methods: We conducted a systematic review to identify English articles published through December 12, 2016 that reported factors associated with nonadherence and/or discontinuation of statins among older persons. Data were pooled via random-effects meta-analysis techniques. Results: Forty-five articles reporting data from more than 1.8 million older statin users from 13 countries were included. The factors associated with increased statin nonadherence were black/non-white race (odds ratio [OR] 1.66, 95% confidence interval [CI] 1.39-1.98), female gender (OR 1.08, 95% CI 1.03-1.13), current smoker (OR 1.12, 95% CI 1.03-1.21), higher copayments (OR 1.38, 95% CI 1.25-1.52), new user (OR 1.58, 95% CI 1.21-2.07), lower number of concurrent cardiovascular medications (OR 1.08, 95% CI 1.06-1.09), primary prevention (OR 1.49, 95% CI 1.40-1.59), having respiratory disorders (OR 1.17, 95% CI 1.12-1.23) or depression (OR 1.11, 95% CI 1.06-1.16), and not having renal disease (OR 1.09, 95% CI 1.04-1.14). The factors associated with increased statin discontinuation were lower income status (OR 1.20, 95% CI 1.06-1.36), current smoker (OR 1.14, 95% CI 1.06-1.23), higher copayment (OR 1.61, 95% CI 1.53-1.70), higher number of medications (OR 1.04, 95% CI 1.01-1.06), presence of dementia (OR 1.18, 95% CI 1.02-1.36), cancer (OR 1.22, 95% CI 1.11-1.33) or respiratory disorders (OR 1.19, 95% CI 1.05-1.34), primary prevention (OR 1.66, 95% CI 1.24-2.22), and not having hypertension (OR 1.13, 95% CI 1.07-1.20) or diabetes (OR 1.09, 95% CI 1.04-1.15). Conclusion: Interventions that target potentially modifiable factors including financial and social barriers, patients' perceptions about disease risk as well as polypharmacy may improve statin use in the older population.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Cumplimiento de la Medicación , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino
15.
J Gerontol A Biol Sci Med Sci ; 73(6): 813-819, 2018 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-28958039

RESUMEN

Background: Older people (aged ≥ 65 years) have distinctive challenges with medication adherence. However, adherence and persistence patterns among older statin users have not been comprehensively reviewed. Methods: As part of a broader systematic review, we searched Medline, Embase, PsycINFO, CINAHL, Database of Abstracts of Reviews of Effects, CENTRAL, and the National Health Service Economic Evaluation Database through December 2016 for English articles reporting adherence and/or persistence among older statin users. Data were analyzed via descriptive methods and meta-analysis using random-effect modeling. Results: Data from more than 3 million older statin users in 82 studies conducted in over 40 countries were analyzed. At 1-year follow-up, 59.7% (primary prevention 47.9%; secondary prevention 62.3%) of users were adherent (medication possession ratio [MPR] or proportion of days covered [PDC] ≥ 80%). For both primary and secondary prevention subjects, 1-year adherence was worse among individuals aged more than 75 years than those aged 65-75 years. At 3 and ≥10 years, 55.3% and 28.4% of users were adherent, respectively. The proportion of users persistent at 1-year was 76.7% (primary prevention 76.0%; secondary prevention 82.6%). Additionally, 68.1% and 61.2% of users were persistent at 2 and 4 years, respectively. Among new statin users, 48.2% were nonadherent and 23.9% discontinued within the first year. The proportion of statin users who were adherent based on self-report was 85.5%. Conclusions: There is poor short and long term adherence and persistence among older statin users. Strategies to improve adherence and reduce discontinuation are needed if the intended cardiovascular benefits of statin treatment are to be realized.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Cumplimiento de la Medicación , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino
16.
Am J Trop Med Hyg ; 98(1): 216-220, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29141720

RESUMEN

The target end date for the global elimination of trachoma as a public health problem is 2020. As countries begin the process for submitting their dossier for the validation of elimination of trachoma as a public health problem, strategies for post-validation surveillance must be considered. Seroprevalence of antibodies against antigens from the causative bacteria Chlamydia trachomatis (Ct) in young children has been shown to reflect trachomatous inflammation-follicular (TF) rates in both endemic and previously endemic settings. However, none of these studies has directly compared age seroprevalence in the same communities before and after mass drug administration (MDA) for trachoma. Here we report a marked shift in age seroprevalence curves in four villages in Kapilvastu District, Nepal, before and after MDA. Clinical examinations were performed and blood was taken before (N = 659) and 5 years after (N = 646) MDA. Rates of TF decreased from 17.6% in ≤ 9-year-olds before MDA (N = 52) to 0% in ≤ 9-year-olds (N = 73) after MDA. Positive antibody responses to Ct in the entire population decreased from 82.1% pre-MDA to 35.8% post-MDA, whereas those among ≤ 9-year-olds decreased from 59.6% to 4.1%. These data show that the postintervention decrease in TF was reflected in a drop in anti-Ct antibody responses, suggesting that antibody responses could be useful indicators for post-validation surveillance.


Asunto(s)
Chlamydia trachomatis , Administración Masiva de Medicamentos , Tracoma/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Niño , Preescolar , Chlamydia trachomatis/inmunología , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Nepal/epidemiología , Estudios Seroepidemiológicos , Tracoma/tratamiento farmacológico , Tracoma/prevención & control , Adulto Joven
18.
Sex Transm Dis ; 44(10): 586-592, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28876289

RESUMEN

BACKGROUND: Gonorrhoea notifications are rapidly rising in men who have sex with men (MSM). We developed a model to assess mouthwash as a novel intervention for gonorrhoea control. METHODS: We developed a model of Neisseria gonorrhoeae (NG) transmission to explain anatomic site-specific prevalence of gonorrhoea among MSM. The model was calibrated to available epidemiological and behavioral data. We estimated the contribution of various sexual acts to gonorrhoea incidence and evaluate the potential impacts of screening scale-up and utilization of mouthwash on the gonorrhoea epidemic. RESULTS: We calibrated the model to prevalence of oropharyngeal, anal, and urethral gonorrhoea of 8.6% (7.7-9.5%), 8.3% (7.4-9.1%), and 0.20% (0.04-0.35%), respectively, among MSM. Oropharynx to oropharynx transmission through kissing is estimated to account for nearly three quarters of all incident cases (71.6% [64.4-80.5%]) of gonorrhoea in MSM. Substantially increasing annual oropharynx screening for gonorrhoea from the current 40% to 100% may only halve the prevalence of gonorrhoea in MSM. In contrast, the use of mouthwash with moderate efficacy (additional 1% clearance per daily use) would further reduce the corresponding prevalence rates to 3.1% (2.2-4.4%), 3.8% (2.3-4.9%), and 0.10% (0.06-0.11%), and a high-efficacy mouthwash (additional 1.5% clearance per daily use) may further halve the gonorrhoea prevalence. Without oropharynx to oropharynx transmission, we could not replicate current prevalence data. CONCLUSIONS: Despite a dearth of empirical data, our model suggests that kissing could potentially play an important role in NG transmission among MSM. Control through sexually transmitted infection screening alone is unlikely to have a substantial impact on the gonorrhoea epidemic in MSM.


Asunto(s)
Gonorrea/transmisión , Modelos Teóricos , Antisépticos Bucales/uso terapéutico , Neisseria gonorrhoeae/fisiología , Canal Anal/microbiología , Coito , Gonorrea/epidemiología , Gonorrea/microbiología , Gonorrea/prevención & control , Homosexualidad Masculina , Humanos , Masculino , Orofaringe/microbiología , Prevalencia , Conducta Sexual , Minorías Sexuales y de Género , Uretra/microbiología
19.
Vaccine ; 35(37): 4923-4929, 2017 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-28789853

RESUMEN

BACKGROUND: We investigated the effectiveness and cost-effectiveness of a targeted human papillomavirus (HPV) vaccination program for young (15-26) men who have sex with men (MSM). METHODS: We developed a compartmental model to project HPV epidemic trajectories in MSM for three vaccination scenarios: a boys program, a targeted program for young MSM only and the combination of the two over 2017-2036. We assessed the gain in quality-adjusted-life-years (QALY) in 190,000 Australian MSM. RESULTS: A targeted program for young MSM only that achieved 20% coverage per year, without a boys program, will prevent 49,283 (31,253-71,500) cases of anogenital warts, 191 (88-319) person-years living with anal cancer through 2017-2036 but will only stablise anal cancer incidence. In contrast, a boys program will prevent 82,056 (52,100-117,164) cases of anogenital warts, 447 (204-725) person-years living with anal cancers through 2017-2036 and see major declines in anal cancer. This can reduce 90% low- and high-risk HPV in young MSM by 2024 and 2032, respectively, but will require vaccinating ≥84% of boys. Adding a targeted program for young MSM to an existing boys program would prevent an additional 14,912 (8479-21,803) anogenital wart and 91 (42-152) person-years living with anal cancer. In combination with a boys' program, a catch-up program for young MSM will cost an additional $AUD 6788 ($4628-11,989) per QALY gained, but delaying its implementation reduced its cost-effectiveness. CONCLUSIONS: A boys program that achieved coverage of about 84% will result in a 90% reduction in HPV. A targeted program for young MSM is cost-effective if timely implemented.


Asunto(s)
Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/uso terapéutico , Adolescente , Adulto , Australia , Análisis Costo-Beneficio , Homosexualidad Masculina/estadística & datos numéricos , Humanos , Masculino , Modelos Teóricos , Años de Vida Ajustados por Calidad de Vida , Adulto Joven
20.
Med J Aust ; 206(10): 455-460, 2017 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-28566073

RESUMEN

Emerging infectious diseases (EIDs) are infectious diseases whose incidence has increased in humans in the past 20 years or could increase in the near future. EID agents may represent a threat to blood safety if they infect humans, cause a clinically significant illness, include an asymptomatic blood phase in the course of infection, and are transmissible by transfusion. EID agents are typically not well characterised, but there is a consensus that we can expect ongoing outbreaks. Strategies to manage the risk to blood safety from EIDs include ongoing surveillance, regular risk assessments, modelling transfusion transmission risk, and deferral of donors with a recent travel history to outbreak areas. The 2015-16 Zika virus (ZIKV) outbreak in the Americas is the largest reported ZIKV outbreak to date, and it highlights the unpredictable nature of EID outbreaks and how quickly they can become a major public health problem. This ZIKV outbreak has provided evidence of a causal link between the virus and microcephaly in newborns. In assessing the potential risk of ZIKV to blood safety in Australia, it should be noted that a relatively small number of imported ZIKV infections have been reported in Australia, there have been no reported cases of local ZIKV transmission, and the geographical distribution of the potential ZIKV mosquito vector in Australia (Aedes aegypti) is limited to northern Queensland. Moreover, reported transfusion-transmitted ZIKV cases worldwide are rare. At present, ZIKV represents a low risk to blood safety in Australia.


Asunto(s)
Seguridad de la Sangre/normas , Enfermedades Transmisibles Emergentes/epidemiología , Brotes de Enfermedades/estadística & datos numéricos , Viaje , Infección por el Virus Zika/epidemiología , Aedes/virología , Animales , Australia , Humanos , Incidencia , Microcefalia/epidemiología , Salud Pública , Factores de Riesgo , Virus Zika , Infección por el Virus Zika/transmisión
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA