Project description:We investigated the genetics and evolution of West Nile virus (WNV) since initial detection in the United States in 1999 on the basis of continual surveillance studies in the Houston, Texas, USA, metropolitan area (Harris County) as a surrogate model for WNV evolution on a national scale. Full-length genomic sequencing of 14 novel 2010-2012 WNV isolates collected from resident birds in Harris County demonstrates emergence of 4 independent genetic groups distinct from historical strains circulating in the greater Houston region since 2002. Phylogenetic and geospatial analyses of the 2012 WNV isolates indicate closer genetic relationship with 2003-2006 Harris County isolates than more recent 2007-2011 isolates. Inferred monophyletic relationships of these groups with several 2006-2009 northeastern US isolates supports potential introduction of a novel WNV strain in Texas since 2010. These results emphasize the need to maintain WNV surveillance activities to better understand WNV transmission dynamics in the United States.
Project description:While the early start and higher intensity of the 2012/13 influenza A virus (IAV) epidemic was not unprecedented, it was the first IAV epidemic season since the 2009 H1N1 influenza pandemic where the H3N2 subtype predominated. We directly sequenced the genomes of 154 H3N2 clinical specimens collected throughout the epidemic to better understand the evolution of H3N2 strains and to inform the H3N2 vaccine selection process. Phylogenetic analyses indicated that multiple co-circulating clades and continual antigenic drift in the haemagglutinin (HA) of clades 5, 3A, and 3C, with the evolution of a new 3C subgroup (3C-2012/13), were the driving causes of the epidemic. Drift variants contained HA substitutions and alterations in the potential N-linked glycosylation sites of HA. Antigenic analysis demonstrated that viruses in the emerging subclade 3C.3 and subgroup 3C-2012/13 were not well inhibited by antisera generated against the 3C.1 vaccine strains used for the 2012/13 (A/Victoria/361/2011) or 2013/14 (A/Texas/50/2012) seasons. Our data support updating the H3N2 vaccine strain to a clade 3C.2 or 3C.3-like strain or a subclade that has drifted further. They also underscore the challenges in vaccine strain selection, particularly regarding HA and neuraminidase substitutions derived during laboratory passage that may alter antigenic testing accuracy.
Project description:The gold-standard therapy for the treatment of aortic arch pathologies is conventional open surgery. Recently, total endovascular aortic arch replacement with branched stent-grafts has been introduced into clinical practice with the aim of reducing invasiveness especially in selected high-risk patients. The aim of this review is to describe the two most commonly used branched devices for endovascular arch stent-grafting: Nexus (Endospan, Herzlia, Israle) and RelayBranch (Terumo Aortic, Glasgow, United Kingdom). Nexus is a CE-certified off-the-shelf, single branch, double stent graft system. It consists of two different components: a main module for the aortic arch and the descending aorta with a side-branch for the brachiocephalic artery (BCA), and a curved module for the ascending aorta that lands into the sino-tubular junction and connects to the main module through a side-facing self-protecting sleeve. Nexus may be used in urgent-emergency cases and also in patients with only one suitable supra-aortic target vessel but, on the other hand, it makes cerebral blood flow dependent on one source vessel only. The RelayBranch Thoracic Stent-Graft System is a custom made, double branched endograft with a wide window on its superior portion to accommodate two inner tunnels for BCA and left common carotid artery connection; bilateral cervical accesses are generally used to advance guidewires for catheterization of the inner tunnels in a retrograde fashion. RelayBranch can be customized on every patient's specific anatomy and provides a double blood source for the brain, but it cannot be used in urgent-emergency conditions. Therefore, in order to optimize outcomes, the choice of the most appropriate device should be made considering pros and cons of each system and patient's anatomy by an experienced aortic team. In conclusion, total endovascular aortic arch exclusion is a promising reality in selected high-risk patients.
Project description:BackgroundCharacterizing invasive mold infection (IMI) epidemiology in the context of large flooding events is important for public health planning and clinical decision making.MethodsWe assessed IMI incidence (per 10 000 healthcare encounters) 1 year before and after Hurricane Harvey at 4 hospitals in Houston, Texas. Potential IMI cases were assigned as proven or probable cases using established definitions, and surveillance cases using a novel definition. We used rate ratios to describe IMI incidence and multivariable logistic regression to examine patient characteristics associated with IMI case status.ResultsIMI incidence was significantly higher posthurricane (3.69 cases) than prehurricane (2.50 cases) (rate ratio, 1.48 [95% confidence interval, 1.10-2.00]), largely driven by surveillance IMI cases. Aspergillus was the most common species cultured (33.5% prehurricane and 39.9% posthurricane). About one-quarter (25.8%) of IMI patients lacked classical IMI risk factors such as hematologic malignancy and transplantations. Overall, 45.1% of IMI patients received intensive care, and in-hospital all-cause mortality was 24.2%.ConclusionsIMI incidence likely increased following Hurricane Harvey and outcomes for IMI patients were severe. Patient and clinician education on IMI prevention and identification is warranted, particularly as the frequency of extreme weather events increases due to climate change.
Project description:Introduction and objectivesThe management of kidney stone disease has changed dramatically over the past 30 years. In particular, ureteroscopy (URS) has become a more efficacious procedure with less morbidity. As a result, based on physician surveys and reports from single centre series the rate of URS appears to have increased over time. However, large population-based evaluations to assess the changes over time in the surgical treatment of kidney stone disease have not been conducted. Our objective was to evaluate population-based trends in the use of extracorporeal shockwave lithotripsy (SWL), URS and percutaneous nephrolithotomy (PCNL) over the past 20 years, in Ontario.MethodsUsing the Ontario Health Insurance Plan physician claims database we conducted a population-based cross-section time series analysis by identifying all kidney stone treatments performed between July 1, 1991 and Dec. 31, 2010, in the province of Ontario. The primary endpoint was the proportion of all stone treatments represented by each modality, which was calculated for every 3-month block over the study period. Exponential smoothing models were utilized to assess for trends over time in the percent utilization of each of SWL, URS and PCNL.ResultsWe identified 194,781 kidney stone treatments between July 1, 1991 and Dec. 31, 2010. A total of 96,807 SWL treatments, 83,923 URS treatments and 14,051 PCNL treatments were performed. We observed a significant trend over time for decreased utilization of SWL (68.5% to 33.7%, p<0.0001) and an increase in URS utilization (24.6% to 59.5%, p=0.0002), while no change over time was found for PCNL (6.88% to 6.85%, p=0.97) (Fig. 1). By the end of 2004, URS had become the most widely used procedure.ConclusionsOur population-based study confirms the increased use of URS over time suggested by physician survey and single centre retrospective series. Accordingly, the utilization of SWL has decreased in a reciprocal fashion.
Project description:Endovascular repair has been introduced to decrease the morbidity and mortality associated with open surgical repair of aortic arch pathology. We illustrate total percutaneous transfemoral approach with a 3-vessel inner branch stent-graft to treat aortic arch aneurysm. (Level of Difficulty: Advanced.) Graphical abstract
Project description:Although urban community food gardens have the capacity to strengthen and support neighborhoods in need, the benefits of such operations must be considered in tandem with the potential risks associated with urban environmental contamination. Therefore, research is needed to characterize existing community gardens in urban areas. In the present study, a survey of Houston, TX, community gardeners (N = 20) was conducted to better understand their risk-based knowledge and perceptions, current gardening practices, and willingness to implement risk mitigation measures. Soil samples collected from the beds (N = 22) and surrounding grounds (N = 24) of existing community garden sites in Houston, TX, were screened for trace and heavy metals using X-ray fluorescence spectrometry. The survey indicated that community gardeners had few concerns with regard to potential soilborne hazards and were generally willing to use diverse strategies to reduce potential hazards related to garden soil contamination. Ground and garden bed soil collected from community gardens were found to have excess concentrations of arsenic compared to federal health screening limits. The information provided here provides insight into possible discordance between community gardening risk perception and contamination risk that could be addressed through outreach, engagement, and remediation approaches.
Project description:Tropical diseases cause significant morbidity among the world's poorest populations. Although more common in low- and middle-income countries, tropical diseases are also found among underserved populations living in high-income countries such as the United States. The National School of Tropical Medicine at Baylor College of Medicine and the Harris Health System founded a tropical medicine clinic-the Harris Health Tropical Medicine Clinic (HHTMC)-in Houston in 2011 in response to tropical disease-related morbidity in Texas. We conducted a retrospective chart review of a sample of patients older than 18 years of age who were referred to the HHTMC between October 2011 and January 2020. Of the 523 patients reviewed, 185 (35.4%) had mycobacterial infections, 184 (35.2%) had parasitic infections, 38 (7.3%) had fungal infections, 16 (3.1%) had eosinophilia without a confirmed clinical diagnosis, 28 (5.4%) had bacterial infections, and 13 (2.5%) had viral infections. The most common infections overall were extrapulmonary and latent tuberculosis (n = 169), neurocysticercosis (n = 78), strongyloidiasis (n = 28), Chagas disease (n = 25), and schistosomiasis (n = 12). The epidemiology of tropical diseases in the United States is understudied at national and regional levels. This 10-year retrospective study contributes to bridging this knowledge gap by detailing the frequencies of tropical disease diagnoses made at the HHTMC in Houston, TX. These data highlight areas for advancement in the field of tropical medicine within the United States, such as improving front-line health-care provider education; establishing tropical medicine clinics in areas of high prevalence such as the Gulf Coast, Appalachia, and urban areas; and developing comprehensive, systematic national tropical disease screening programs and patient registries.