Effect of high-volume insecticide spraying on sand fly vectors in household gardens in Spain.

This study investigated the efficacy of high-volume spraying with the adulticide α-cypermethrin alone and in combination with the larvicide diflubenzuron on the density of sand flies in gardens of three detached households in periurban areas in southeast Spain. Treatments were applied four times between June and August 2016, and four nearby sites, two households and two non-urbanized sites, were untreated controls. The number of sand flies collected between May and October 2016 using sticky interception and light attraction traps, was 4446 specimens. Species identified morphologically included Sergentomyia minuta (n = 2101; 48%), Phlebotomus perniciosus (n = 1922; 44%), Phlebotomus papatasi (n = 173; 4%), Phlebotomus sergenti (n = 161; 4%) and Phlebotomus ariasi (n = 36; 1%). Sand flies were detected in both treated and untreated sites. The proportion of positive sticky traps and the median (range) density of sand flies in positive traps were 61% traps and 7 (2-172) sand flies/m2 /day in untreated sites, and 43% traps and 4 (1-56) sand flies/m2 /day in treated sites (p < 0.05). Similarly, for light traps, it was 96% traps and 30 (3-168) flies/trap/day, and 83% traps and 3 (1-12) sand flies/trap/day, respectively (p < 0.05). However, sand fly density followed a comparable seasonal pattern in untreated and treated sites and did not consistently decrease following insecticide applications. These results were confirmed with mixed negative binomial modelling of sand fly density adjusted for time since application, month, environmental setting and site. The limited efficacy of the treatments, added to their cost, the impact of insecticides on non-target organisms and human health, and the risk of development of insecticide resistance, should dissuade similar outdoor applications to control sand fly vector populations in residential areas.

A Low-Cost Active Reflector for Interferometric Monitoring Based on Sentinel-1 SAR Images.

The effectiveness of radar interferometric techniques in non-urban areas can often be compromised due to the lack of stable natural targets. This drawback can be partially compensated through the installation of reference targets, characterized by a bright and stable radar response. The installation of passive corner reflectors (PCR) often represents a valid aid, but these objects are usually cumbersome, and suffer from severe weather conditions; furthermore, the installation of a PCR can be difficult and costly, especially in places with hard accessibility. Active reflectors (AR) represent a less cumbersome alternative to PCRs, while still providing a stable phase response. This paper describes the design, implementation, and test of an AR prototype, designed to operate with the Sentinel-1 synthetic aperture radar (SAR), aimed at providing a fair performance/cost benefit. These characteristics, obtained through a tradeoff between the use of off-the-shelf components and a simple architecture, can make the setup of a dense network (i.e., tens of devices) in the monitored areas feasible. The paper reports the design, implementation, and the analysis of different tests carried out in a laboratory, and in a real condition in the field, to illustrate AR reliability and estimate its phase stability.

Depth-resolved Mueller matrix polarimetry microscopy of the rat cornea.

Mueller matrix polarimetry (MMP) is a promising linear imaging modality that can enable visualization and measurement of the polarization properties of the cornea. Although the distribution of corneal birefringence has been reported, depth resolved MMP imaging of the cornea has not been archived and remains challenging. In this work, we perform depth-resolved imaging of the cornea using an improved system that combines Mueller matrix reflectance and transmission microscopy together with nonlinear microscopy utilizing second harmonic generation (SHG) and two photon excitation fluorescence (TPEF). We show that TPEF can reveal corneal epithelial cellular network while SHG can highlight the presence of corneal stromal lamellae. We then demonstrate that, in confocal reflectance measurement, as depth increases from 0 to 80 µm both corneal depolarization and retardation increase. Furthermore, it is shown that the spatial distribution of corneal depolarization and retardation displays similar complexity in both reflectance (confocal and non-confocal) and transmission measurement, likely due to the strong degree of heterogeneity in the stromal lamellae.

Genetic diversity and phylogenetic relationships between Leishmania infantum from dogs, humans and wildlife in south-east Spain.

Leishmania infantum causes human and canine leishmaniosis. The parasite, transmitted by phlebotomine sand flies, infects species other than dogs and people, including wildlife, although their role as reservoirs of infection remains unknown for most species. Molecular typing of parasites to investigate genetic variability and evolutionary proximity can help understand transmission cycles and designing control strategies. We investigated Leishmania DNA variability in kinetoplast (kDNA) and internal transcribed spacer 2 (ITS2) sequences in asymptomatically infected wildlife (n = 58) and symptomatically and asymptomatically infected humans (n = 38) and dogs (n = 15) from south-east Spain, using single nucleotide polymorphisms (SNPs) and in silico restriction fragment length polymorphism (RFLP) analyses. All ITS2 sequences (n = 76) displayed a 99%-100% nucleotide identity with a L. infantum reference sequence, except one with a 98% identity to a reference Leishmania panamensis sequence, from an Ecuadorian patient. No heterogeneity was recorded in the 73 L. infantum ITS2 sequences except for one SNP in a human parasite sequence. In contrast, kDNA analysis of 44 L. infantum sequences revealed 11 SNP genotypes (nucleotide variability up to 4.3%) and four RFLP genotypes including B, F and newly described S and T genotypes. Genotype frequency was significantly greater in symptomatic compared to asymptomatic individuals. Both methods similarly grouped parasites as predominantly or exclusively found in humans, in dogs, in wildlife or in all three of them. Accordingly, the phylogenetic analysis of kDNA sequences revealed three main clusters, two as a paraphyletic human parasites clade and a third including dogs, people and wildlife parasites. Results suggest that Leishmania infantum genetics is complex even in small geographical areas and that, probably, several independent transmission cycles take place simultaneously including some connecting animals and humans. Investigating these transmission networks may be useful in understanding the transmission dynamics, infection risk and therefore in planning L. infantum control strategies.

Vaccine Effectiveness against DS-1-Like Rotavirus Strains in Infants with Acute Gastroenteritis, Malawi, 2013-2015.

Atypical DS-1-like G1P[8] rotaviruses emerged in 2013 in Malawi after rotavirus vaccine introduction. Vaccine effectiveness among infants hospitalized with acute DS-1-like G1P[8] rotavirus gastroenteritis was 85.6% (95% CI 34.4%-96.8%). These findings suggest that vaccine provides protection against these strains despite their emergence coinciding with vaccine introduction.

Towards mm-wave spectroscopy for dielectric characterization of breast surgical margins.

PURPOSE: The evaluation of the surgical margin in breast conservative surgery is a matter of general interest as such treatments are subject to the critical issue of margin status as positive surgical margins can undermine the effectiveness of the procedure. The relatively unexplored ability of millimeter-wave (mm-wave) spectroscopy to provide insight into the dielectric properties of breast tissues was investigated as a precursor to their possible use in assessment of surgical margins. METHODS: We assessed the ability of a mm-wave system with a roughly hemispherical sensitive volume of ∼3 mm radius to distinguish malignant breast lesions in prospectively and consecutively collected tumoral and non-tumoral ex-vivo breast tissue samples from 91 patients. We characterized the dielectric properties of 346 sites in these samples, encompassing malignant, fibrocystic disease and normal breast tissues. An expert pathologist subsequently evaluated all measurement sites. RESULTS: At multivariate analysis, mm-wave dielectric properties were significantly correlated to histologic diagnosis and fat content. Further, using 5-fold cross-validation in a Bayesian logistic mixed model that considered the patient as a random effect, the mm-wave dielectric properties of neoplastic tissues were significantly different from normal breast tissues, but not from fibrocystic tissue. CONCLUSION: Reliable discrimination of malignant from normal, fat-rich breast tissue to a depth compatible with surgical margin assessment requirements was achieved with mm-wave spectroscopy.

Nuevos retos en gestión de vectores en salud pública: la mosca negra en Murcia (España) / New public health challenges in vector management: black flies in Murcia (Spain)

Hasta ahora no se habían detectado molestias causadas por simúlidos (Diptera: Simuliidae) en la Región de Murcia. En septiembre de 2016, el ayuntamiento de Ojós contactó con la Dirección General de Salud Pública en relación con una plaga de insectos en la localidad, probablemente mosquitos. Tras muestrear con una trampa BG-sentinel 2, capturar insectos adultos con aspirador entomológico, y larvas y pupas en muestras de cañas sumergidas, la especie implicada se identificó como Simulium sergenti. Esta especie no parece ser especialmente antropófila y, por tanto, el riesgo para la salud de los vecinos se consideró bajo, pero las molestias causadas por la gran cantidad de moscas afectaron a la calidad de vida de las personas en la localidad. Se recomendó un plan de gestión de simúlidos para la zona afectada, tratando el río con Bacillus thuringiensis var. Israelensis (AU)

Historically, no black fly (Diptera: Simuliidae) nuisance has been reported in the Murcia Region. Back in September 2016 the Ojós City Council has contacted the Regional Public Health General Directorate for help regarding a local insect nuisance, most probably based on mosquitoes. After sampling with a BG-sentinel 2 trap, collecting adult specimens with an entomological aspirator, and collect larvae and pupae on submerged giant cane stalks at the river, it turned out that Simulium sergenti was the insect species causing the nuisance. This species is not considered particularly anthropophilic; therefore, a low vector risk for human health was considered. However, the high fly density impaired the life quality of the people at the village. A management plan was recommended, treating the river with Bacillus thuringiensis var israelensis (AU)

[New public health challenges in vector management: black flies in Murcia (Spain)]. / Nuevos retos en gestión de vectores en salud pública: la mosca negra en Murcia (España).

Historically, no black fly (Diptera: Simuliidae) nuisance has been reported in the Murcia Region. Back in September 2016 the Ojós City Council has contacted the Regional Public Health General Directorate for help regarding a local insect nuisance, most probably based on mosquitoes. After sampling with a BG-sentinel 2 trap, collecting adult specimens with an entomological aspirator, and collect larvae and pupae on submerged giant cane stalks at the river, it turned out that Simulium sergenti was the insect species causing the nuisance. This species is not considered particularly anthropophilic; therefore, a low vector risk for human health was considered. However, the high fly density impaired the life quality of the people at the village. A management plan was recommended, treating the river with Bacillus thuringiensis var israelensis.

A Monte Carlo Analysis of Error Associated With Two-Wavelength Algorithms for Retinal Oximetry.

Purpose: Two-wavelength algorithms aimed at the extrapolation of retinal vasculature optical properties are being used in the clinical setting. Although robust, this approach has some clear mathematical limitations. We have conducted an in-depth study of this methodology and report on the limits and benefit of this approach. Methods: We used a well-tested, voxel-based Monte Carlo model of light transfer into biological tissue combined with a seven-layer model of the human fundus to create reflectance maps of retina vessels at different oxygenation levels. Results: This study shows that the two-wavelength approach works remarkably well in the optimal scenario of known calibration arteries and veins. Errors as a result of choroidal pigmentation and discrepancies in vessel size can be minimized with numerical approaches. When the calibration process deviates largely from physiological values, the technique fails with large errors. Conclusions: The two-wavelength approach is convenient, easy to implement, and suitable in studies where relative rather than absolute knowledge of retinal oximetry is necessary. A robust calibration step is paramount when using this approach.

Effects of Disseminated Mycobacterial Infection on Age-Related Macular Degeneration.

Our patient, in the 7th decade of life, presented with worsening blurry vision over 3 weeks. The pertinent history included nonexudative age-related macular degeneration, recent pulmonary mycobacterial infection, and autoimmune pancreatitis. The patient had decreased visual acuity in both eyes; the remaining findings of our examination were relatively benign. The diagnosis of bilateral exudative age-related macular degeneration was aided by ocular imaging. Not only were exudative changes confirmed, but one modality suggested an underlying occult choroiditis, which presumably fueled a local inflammatory drive leading to evolution of the disease. Given the choroiditis developed in the setting of a recent Mycobacterium chelonae infection, dissemination of the organism must be considered a potential culprit. Additionally, a chronic inflammatory state perhaps played a simultaneous immunologic role. We feel the proposed pathogenic mechanism outlined sufficiently accounts for the rare event, that is, development of subacute bilateral exudative maculopathy. The patient responded well to bilateral intravitreal aflibercept injections. After 1 month, visual acuity was found to be near baseline and ocular imaging showed significant resolution of the exudative changes. An additional follow-up 3 months after confirmed similar stability. This case required thorough investigation of seemingly unrelated components within the patient's history. We stress the importance of obtaining appropriate documentation from fellow health care teams when suspicious clinical presentations arise. During our investigation, we identified cryptic retinal lesions by way of angiography - leading us to recommend usage of such methods in complex cases. We also summarize the implemented aflibercept course and the favorable response to such treatment.

Pharmacokinetic rationale for dosing every 2 weeks versus 4 weeks with intravitreal ranibizumab, bevacizumab, and aflibercept (vascular endothelial growth factor Trap-eye).

PURPOSE: Monthly dosing with inhibitors of vascular endothelial growth factor (VEGF) results in stable or improved visual acuity in most patients with neovascular age-related macular degeneration. However, a minority of patients show little if any response to therapy with persistent or worsening macular fluid. Pharmacokinetic modeling was performed to determine if more frequent dosing with anti-VEGF drugs could be theoretically beneficial. METHODS: A mathematical model comparing the time-dependent relative binding activities of ranibizumab, bevacizumab, and aflibercept (VEGF Trap-eye; VTE) was used to determine the theoretical peak and trough binding activities when the drugs were injected every 14 days and every 28 days. The intravitreal half-lives of ranibizumab, bevacizumab, and the VTE were estimated to be 3.2, 5.6, and 4.8 days, respectively. The relative molar binding activities of ranibizumab, bevacizumab, and the VTE used in the analyses were 1, 0.05 to 0.2, and 140, respectively. The expected peak and trough binding activities for ranibizumab, bevacizumab, and VTE were calculated. Dosing every 2 weeks was performed on selected patients who had a poor response to monthly therapy. RESULTS: Dosing of a drug every 2 weeks resulted in markedly improved trough binding activity, but had little impact on the peak binding activity when calculated through Day 28. The dosing of bevacizumab every 2 weeks resulted in trough binding levels that were superior to monthly dosing with ranibizumab at a dose of 0.5 mg and potentially superior to the levels achieved when ranibizumab was dosed monthly at a dose of 2.0 mg. The VTE displayed superior binding levels for both peak and trough levels even when compared with ranibizumab doses given every 2 weeks. Two case reports demonstrate the clinical usefulness of dosing with anti-VEGF therapy every 2 weeks in eyes with VEGF-dependent macular fluid appearing to be refractory to monthly dosing. CONCLUSION: The theoretical increase in trough binding levels when anti-VEGF drugs are dosed every 2 weeks most likely explains the clinical benefit observed in patients who received biweekly injections after their poor response to monthly therapy. The short-term use of biweekly dosing may be an attractive treatment option for those eyes that show a treatment response within 2 weeks of an injection, but rebound with increased macular fluid after a month. In the future, VTE should provide higher trough levels of anti-VEGF binding activity and eliminate the need for biweekly dosing in those eyes with VEGF-mediated exudation that appear unresponsive to monthly ranibizumab or bevacizumab.

Transient electro-oculogram impairment in unilateral acute idiopathic maculopathy.

Unilateral acute idiopathic maculopathy (UAIM) is a rare distinct entity characterized by acute exudative maculopathy occurring in young persons. The purpose of this case study is to report transient electro-oculogram (EOG) impairment during the acute stage of UAIM. A 16-year-old healthy female with UAIM in the left eye underwent serial visual field, fluorescein angiography, indocyanine green angiography, full-field electroretinogram (ERG), and EOG. Initial visual acuity of the affected left eye was 4/200 with macular subretinal exudates. Indocyanine green angiography disclosed early phase foveal hypocyanescence persisting into late phase along with late phase foci of pinpoint hypocyanescence scattered in the macular and mid-peripheral regions. Standard full-field ERG responses performed 18 days after the onset of symptoms were normal. Standard EOG revealed a marked reduced light-peak to dark-trough amplitude ratio (Arden ratio) of 1.20 left eye (normal >or= 1.7) and a normal ratio of 2.24 right eye. Five weeks later, the left eye improved to 20/50, and the exudative maculopathy resolved with residual irregular foveal hyperpigmentation. Repeat EOG performed 69 days after onset of symptoms showed recovery and normalization of the EOG amplitude ratio of the left eye from 1.20 to 2.54. Transient EOG impairment with a normal full-field ERG may occur during the early stage of UAIM. This finding suggests a more widespread dysfunction of the retinal pigment epithelium in at least some cases of UAIM.