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Effective antiretroviral treatment of HIV-1, defined as continuously undetectable virus in blood, has substantial effects on the infectiousness and spread of HIV.This paper outlines the assessment of the Swedish Reference Group for Antiviral Therapy (RAV) and Public Health Agency of Sweden regarding contagiousness of HIV-infected persons on antiretroviral therapy (ART).

Small Unmanned Aerial Vehicle (UAV) platforms equipped with compact laser scanners provides a low-cost option for many applications, including surveillance, mapping, and reconnaissance. For these applications, semantic segmentation or semantic labeling of each point in the lidar point cloud, is important for scene-understanding. In this work, we evaluate methods for semantic segmentation of three-dimensional (3D) point clouds of outdoor scenes measured with a laser scanner mounted on a small UAV. We compare the performance of four different semantic segmentation methods, which are all applied in a scan-by-scan fashion, on semi-sparse laser data. The best method achieves 95.3% on the three classes ground, vegetation, and vehicle in terms of mean intersection over union (mIoU) on a previously unseen scene from a different geographical area. The results demonstrate that it is possible to achieve good performance on the semantic segmentation task on data measured using a combination of a small UAV and a compact laser scanner.

BackgroundMost HIV infections originate from individuals who are undiagnosed and unaware of their infection. Estimation of this quantity from surveillance data is hard because there is incomplete knowledge abouti)the time between infection and diagnosis (TI) for the general population andii)the time between immigration and diagnosis for foreign-born persons.DevelopmentWe developed a new statistical method for estimating the number of undiagnosed people living with HIV (PLHIV) and the incidence of HIV-1 based on dynamic modeling of heterogenous HIV-1 surveillance data. We formulated a Bayesian non-linear mixed effects model using multiple biomarkers to estimate TI accounting for biomarker correlation and individual heterogeneities. We explicitly model the probability that an HIV-1 infected foreign-born person was infected either before or after immigration to distinguish between endogenous and exogeneous incidence. The incidence estimator allows for direct calculation of the number of undiagnosed persons.ApplicationThe model was applied to surveillance data in Sweden. The dynamic biomarker model was trained on longitudinal data from 31 treatment-naïve patients with well-defined TI, using CD4 counts, BED serology, polymorphisms in HIV-1polsequences, and testing history. The multiple-biomarker model was more accurate than single biomarkers (mean absolute error 1.01 vs ≥ 1.95). We estimate that 813 (95% CI 780-862) PLHIV were undiagnosed in 2015, representing a proportion of 10.8% (95% CI 10.4-11.3%) of all PLHIV.ConclusionsThe proposed methodology will enhance the utility of standard surveillance data streams and will be useful to monitor progress towards and compliance with the 90-90-90 UNAIDS target.Key messagesCombined heterogeneous HIV-1 surveillance data and biomarker data can be used to estimate both local incidence and the number of undiagnosed people living with HIV.Explicit modeling of the dynamics, heterogeneity, and correlation of multiple biomarkers over time improved estimation of time between infection and diagnosis.Explicit modeling of the probability that foreign-born persons were infected before or after immigration improves accuracy of estimates of endogenous incidence and undiagnosed persons living with HIV.The endogenous incidence of HIV-1 in Sweden is declining, despite continued immigration of HIV-1 infected persons.The proportion of undiagnosed PLHIV decreased over 2010-2015 and was estimated to be 10.8% (95% CI, 10.4-11.3%) in 2015.

Hepatitis B virus (HBV) infection remains a global health threat. The World Health Organization (WHO) established a goal to eliminate HBV infection as a public health threat by 2030, and defined targets for key interventions to achieve that goal. We evaluated HBV burden and relevant national recommendations for progress towards WHO targets in circumpolar countries. Viral hepatitis experts of circumpolar countries were surveyed regarding their country’s burden of HBV, achievement of WHO targets and national public health authority recommendations for HBV prevention and control. Eight of nine circumpolar countries responded. All countries continue to see new HBV infections. Data about HBV prevalence and progress in reaching WHO 2030 elimination targets are lacking. No country was able to report data for all seven WHO target measures. All countries have recommendations targeting the prevention of mother-to-child transmission. Only the USA and Greenland recommend universal birth dose vaccination. Four countries have recommendations to screen persons at high risk for HBV. Existing recommendations largely address prevention; however, recommendations for universal birth dose vaccination have not been widely introduced. Opportunities remain for the development of trackable targets and national elimination planning to screen and treat for HBV to reduce incidence and mortality.

Detecting and identifying objects inside a forest edge on the other side of an open field is an important task in defence and security applications. This can be difficult to achieve with passive imaging sensors because of the partial obscuration by the foliage. High-resolution 3D imaging enables separation of hidden objects from branches and leaves and can provide data for detection, recognition, and identification of partly occluded targets. We use a photon counting lidar system with panoramic scanning to produce high quality 3D data for this task. The FOI system is built around the Princeton Lightwave Inc. (PLI) Falcon detector which is a 32×128 pixel array of InGaAs Geiger-mode avalanche photodiodes. The system operates at 1557 nm and has been designed for suitable resolution at standoff ranges of 1 to 2 km. In this paper, we investigate the detection capability when combining measurements from multiple measurement positions. A field trial has been performed where data from the same scene was collected from different sensor positions. The system was mounted on a car and moved between different positions along a road. The measurements were performed first without and then with vehicles in the target area. The distance to the forest edge varied between from approximately 1.0 to 1.5 km, and the difference of the angle of incidence was approximately 45 degrees from the outer positions along the road. To merge the data from the different positions we apply registration of the data sets using derived point clouds to transform all data into a common coordinate system. Data from the different sensor positions is analyzed by overlaying the derived point clouds from the different positions. We compare data from different viewpoints to data from only one viewpoint. The results show that the combined point clouds from multiples positions covers more of scene than from a single position. We also perform change detection using registered point clouds from the same measurement positions. In the change detection we found the changes we had introduced (vehicles and equipment).

Single-photon counting lidar using Geiger-mode avalanche photodiode (GmAPD) arrays can provide high resolution 3D images at kilometer stand-off distances through coincidence processing. 3D data is useful for detection and identification of targets, especially those so occluded by vegetation that only small patches, smaller than the instantaneous field-of-view of a sensor pixel, have free line-of-sight. To cover an area of interest, e.g. the edge of a forest, with spatial resolution high enough to identify targets, a multimegapixel 3D image is needed. Current GmAPD arrays are limited to tens of kilopixels. Even if the technical challenges of larger arrays could be solved, the necessary pulse energy per pixel will still limit the effective number of pixels at longer ranges, especially if nominal ocular hazard distance (NOHD) is a concern or if short pulse fiber lasers should be used. Thus scanning of the sensor field-of-view will probably always be necessary. In this paper we describe activities at FOI to explore the potential of single-photon counting panoramic 3D imaging using a GmAPD array detector. Results from outdoor experiments at up to 1.2 km stand-off distances, in day and night conditions, are shown. The impact of background light, and how this is handled by changing the aperture stop size, is considered. Signal processing techniques to go from scattered photon detections via 3D point clouds to voxel-based scene analysis are described. The results support the position that single-photon counting with GmAPD arrays is suitable for 3D imaging in military applications with kilometer stand-off distances.

Background Sweden has a low HIV prevalence. However, among new HIV diagnoses in 2016, the proportion of late presenters and migrants was high (59% and 81%, respectively). This poses challenges in estimating the proportion of undiagnosed persons living with HIV (PLHIV). Aim To estimate the proportion of undiagnosed PLHIV in Sweden comparing two models with different demands on data availability and modelling expertise. Methods An individual-based stochastic simulation model of HIV positive populations (SSOPHIE) and the incidence method of the European Centre for Disease Prevention and Control (ECDC) HIV Modelling Tool were applied to clinical, surveillance and migration data from Sweden 1980–2016. Results SSOPHIE estimated that the proportion of undiagnosed PLHIV in 2013 was 26% (n = 2,100; 90% plausibility range (PR): 900–5,000) for all PLHIV, 17% (n = 600; 90% PR: 100–2,000) for men who have sex with men (MSM), 35% in male (n = 300; 90% PR: 200–700) and 34% in female (n = 400; 90% PR: 200–800) migrants from sub-Saharan Africa (SSA). The estimates for the ECDC model in 2013 were 21% (n = 2,013; 95% confidence interval (CI): 1,831–2,189) for all PLHIV, 15% (n = 369; 95% CI: 299–434) for MSM and 21% (n = 530; 95% CI: 436–632) for migrants from SSA. Conclusions The proportion of undiagnosed PLHIV in Sweden is uncertain. SSOPHIE estimates had wide PR. The ECDC model estimates were unreliable because migration was not accounted for. Better migration data and estimation methods are required to obtain reliable estimates of proportions of undiagnosed PLHIV in similar settings.

This work addresses the problem of detecting and classifying materials and targets in hyperspectral images based on their reflectance spectrum. Accurate target detection in hyperspectral imagery requires a radiative transfer model that maps between the spectral reflectance domain and the measured radiance domain. Such a model can be employed in two ways for detection – using atmospheric compensation, where the measured hyperspectral radiance image is converted to a reflectance image, and using forward modeling, where the target reflectance spectrum is converted to an at-sensor target radiance spectrum. This work presents a forward modeling detection method that utilizes in-scene information to estimate the parameters in the radiative transfer model. Uncertainty in the radiative transfer model and variability of the target spectra are captured using a constrained subspace model for the target. Target detection using library spectra and target rediscovery are evaluated in hyperspectral images of a complex urban scene.

We summarised available hepatitis C virus (HCV) surveillance data for 2012–14 from Arctic/sub-Arctic countries/regions. We sent a HCV data collection template by email to public health authorities in all jurisdictions. Population statistics obtained from census sources for each country were used to estimate rates of reported acute and chronic/undifferentiated HCV cases. Seven countries with Arctic regions (Canada, Denmark, Finland, Greenland, Norway, Sweden and the United States, represented by the state of Alaska), including three Canadian territories and one province, as well as 11 Russian subnational Arctic regions, completed the data collection template. Data on acute HCV infection during 2014 was available from three Arctic countries and all Russian Arctic regions (rate range 0/100,000 population in Greenland, as well as Nenets and Chukotka Automous Okrugs (Russian subnational Arctic regions) to 3.7/100,000 in the Russian Republic of Komi). The rate of people with chronic/undifferentiated HCV infection in 2014 ranged from 0/100,000 in Greenland to 171.2/100,000 in Alaska. In most countries/regions, the majority of HCV-infected people were male and aged 19–64 years. Differences in surveillance methods preclude direct comparisons of HCV surveillance data between Arctic countries/regions. Our data can inform future efforts to develop standardised approaches to HCV surveillance in the Arctic countries/regions by identifying similarities/differences between the surveillance data collected.

Three-dimensional (3D) reconstruction of buildings is an active research area with applications in e.g. city planning, environmental simulations, and city navigation. Automatic 3D building reconstruction methods based on point clouds from laser scanning or methods based on high resolution dense photogrammetric point clouds are common in the literature. In applications where large land areas need to be covered regularly it is not practical to use laser scanning or acquire images with high resolution and large image overlaps. In these applications the reconstructed photogrammetric point cloud has low resolution with less building details. We present a method where the most common roof types are classified using a deep convolutional neutral network (CNN) pre-trained using RGB data in this challenging type of data. In addition’ a method for roof height estimation for each roof type is presented to support automatic 3D building reconstruction using model building shapes. Results are shown for a low resolution dense photogrammetric point cloud generated using multi-view stereo reconstruction of standard overlapping aerial images from nationwide data collection. The method is intended to support automated generation of a nationwide 3D landscape model.

EU/EEA HIV Surveillance Network: Daniela Schmid, André Sasse, Dominique Van Beckhoven, Tonka Varleva, Tatjana Nemeth Blazic, Linos Hadjihannas, Maria Koliou, Marek Maly, Susan Cowan, Kristi Rüütel, Kirsi Liitsola, Mika Salminen, Françoise Cazein, Josiane Pillonel, Florence Lot, Barbara Gunsenheimer-Bartmeyer, Stavros Patrinos, Dimitra Paraskeva, Maria Dudas, Haraldur Briem, Gudrun Sigmundsdottir, Derval Igoe, Kate O'Donnell, Darina O'Flanagan, Barbara Suligoi, Šarlote Konova, Sabine Erne, Irma Caplinskiene, Aurélie Fischer, Jackie Maistre Melillo, Tanya Melillo, Eline Op de Coul, Hans Blystad, Magdalena Rosinska, Isabel Aldir, Helena Cortes Martins, Mariana Mardarescu, Peter Truska, Irena Klavs, Asunción Díaz, Maria Axelsson, Valerie Delpech Helena Cortes Martins: Departamento de Doenças Infeciosas do Instituto Nacional de Saúde Doutor Ricardo Jorge. Background: The HIV burden is increasing in older adults in the European Union (EU) and European Economic Area (EEA). We investigated factors associated with HIV diagnosis in older adults in the 31 EU/EEA countries during a 12 year period. Methods: In this analysis of surveillance data, we compared data from older people (aged ≥50 years) with those from younger people (aged 15–49 years). We extracted new HIV diagnoses reported to the European Surveillance System between Jan 1, 2004, and Dec 31, 2015, and stratified them by age, sex, migration status, transmission route, and CD4 cell count. We defined late diagnosis as CD4 count of less than 350 cells per μL at diagnosis and diagnosis with advanced HIV disease as less than 200 cells per μL. We compared the two age groups with the χ² test for difference, and used linear regression analysis to assess temporal trends. Findings: During the study period 54 102 new HIV diagnoses were reported in older adults. The average notification rate of new diagnoses was 2·6 per 100 000 population across the whole 12 year period, which significantly increased over time (annual average change [AAC] 2·1%, 95% CI 1·1–3·1; p=0·0009). Notification rates for new HIV diagnoses in older adults increased significantly in 16 countries in 2004–15, clustering in central and eastern EU/EEA countries. In 2015, compared with younger adults, older individuals were more likely to originate from the reporting country, to have acquired HIV via heterosexual contact, and to present late (p

Security systems at airports, borders, and other public areas require high throughput screening at the same time as a high level of protection against possible threats is achieved. New safe stand-off systems with automatic detection of concealed objects that operate in the submillimeter wave region are being developed to meet the need for fast screening and respected privacy. These new technologies include radar 3D imaging of moving persons. Real-time fame rates are desired in these scanning radar 3D imaging systems to achieve high throughput. High throughput can also be achieved at lower near real-time frame rates if the 3D images can be motion compensated before detection of concealed objects. In this paper we present a method for motion compensation of submillimeter wave 3D imaging radar data used for security screening. We demonstrate the method on simulated 3D radar data with known motion errors with good results.

Conclusion Kinetic oscillation stimulation (KOS) of nasal mucosa at low frequency seems to be a possibly effective and safe short-term treatment of non-allergic nasal stuffiness. Objective To assess the relief of rhinitis symptoms, especially stuffiness, by comparing active treatment, i.e. KOS at low frequency of the nasal mucosa, with placebo. Methods Patients were randomized to active or placebo treatment in this double-blinded parallel design study. Treatment with an inflatable oscillating catheter was administered on day 0, and symptom scores (stuffiness, secretion, and itching) were graded daily until day 14. An overall grading of symptoms from 1 week before treatment and during 14 days thereafter was made at day 14. Eighty-six patients (52 with non-allergic perennial rhinitis, NAR; 34 with rhinitis medicamentosa, RM) were randomized, and 71 were evaluated (active treatment, n = 35; placebo, n = 36). Results Patients with either NAR or RM who received active treatment reported reduced symptom scores by some measures, e.g. median RQSS stuffiness measure fell from 2 to 1 on a scale from 0 to 3 during the week following treatment. No significant effect was observed for patients treated with placebo. Mild side effects were reported.

Detailed phylogenetic analyses were performed to characterize an HIV-1 outbreak among injection drug users (IDUs) in Stockholm, Sweden, in 2006. This study investigated the source and dynamics of HIV-1 spread during the outbreak as well as associated demographic and clinical factors. Seventy Swedish IDUs diagnosed during 2004 to 2007 were studied. Demographic, clinical, and laboratory data were collected, and the V3 region of the HIV-1 envelope gene was sequenced to allow detailed phylogenetic analyses. The results showed that the Stockholm outbreak was caused by a CRF01_AE variant imported from Helsinki, Finland, around 2003, which was quiescent until the outbreak started in 2006. Local Swedish subtype B variants continued to spread at a lower rate. The number of new CRF01_AE cases over a rooted phylogenetic tree accurately reflected the transmission dynamics and showed a temporary increase, by a factor of 12, in HIV incidence during the outbreak. Virus levels were similar in CRF01_AE and subtype B infections, arguing against differences in contagiousness. Similarly, there were no major differences in other baseline characteristics. Instead, the outbreak in Stockholm (and Helsinki) was best explained by an introduction of HIV into a standing network of previously uninfected IDUs. The combination of phylogenetics and epidemiological data creates a powerful tool for investigating outbreaks of HIV and other infectious diseases that could improve surveillance and prevention.

In 2014 the Public Health Agency of Sweden and the Swedish Reference Group for Antiviral Therapy (RAV) conducted a review and analysis of the state of knowledge on the duration of follow-up after exposure to human immunodeficiency virus (HIV). Up until then a follow-up of 12 weeks after exposure had been recommended, but improved tests and new information on early diagnosis motivated a re-evaluation of the national recommendations by experts representing infectious diseases and microbiology, county medical officers, the RAV, the Public Health Agency, and other national authorities. Based on the current state of knowledge the Public Health Agency of Sweden and the RAV recommend, starting in April 2015, a follow-up period of 6 weeks after possible HIV-1 exposure, if HIV testing is performed using laboratory-based combination tests detecting both HIV antibody and antigen. If point-of-care rapid HIV tests are used, a follow-up period of 8 weeks is recommended, because currently available rapid tests have insufficient sensitivity for detection of HIV-1 antigen. A follow-up period of 12 weeks is recommended after a possible exposure for HIV-2, since presently used assays do not include HIV-2 antigens and only limited information is available on the development of HIV antibodies during early HIV-2 infection. If pre- or post-exposure prophylaxis is administered, the follow-up period is recommended to begin after completion of prophylaxis. Even if infection cannot be reliably excluded before the end of the recommended follow-up period, HIV testing should be performed at first contact for persons who seek such testing.

A method for determining the water content at the interface between a press felt and a paper web has been developed. The water content was obtained by subtracting the estimated volume of the indent ...

In this paper, we show that the void space in 3D images of paper can be successfully divided into subspaces using digital volume image analysis. The subspaces are denoted pores, which are connected ...

Fast detection and analysis of dangerous substances from longer distances is highly desired in many security applications. Imaging Raman spectroscopy is a novel multi-spectral imaging technique designed for stand-off screening and detection of explosive substances. In this paper we present a method for detection and classification of explosive substances in multi-spectral image sequences from imaging Raman spectroscopy using linear subspace matching. Our approach uses limited spectral information and is computationally efficient, which enables fast screening of interesting areas. The performance of the method is evaluated on real stand-off measurements from a demonstrator system. We show that the method can detect and classify substances with high accuracy.

Seven countries within the European Defence Agency (EDA) framework are joining effort in a four year project (2009-2013) on Detection in Urban scenario using Combined Airborne imaging Sensors (DUCAS) . Data has been collected in a joint field trial including instrumentation for 3D mapping, hyperspectral and high resolution imagery together with in situ instrumentation for target, background and atmospheric characterization. Extensive analysis with respect to detection and classification has been performed. Progress in performance has been shown using combinations of hyperspectral and high spatial resolution sensors.

Surveillance with automated positioning and tracking of subjects and vehicles in 3D is desired in many defence and security applications. Camera systems with stereo or multiple cameras are often used for 3D positioning. In such systems, accurate camera calibration is needed to obtain a reliable 3D position estimate. There is also a need for automated camera calibration to facilitate fast deployment of semi-mobile multi-camera 3D positioning systems. In this paper we investigate a method for automatic calibration of the extrinsic camera parameters (relative camera pose and orientation) of a multi-camera positioning system. It is based on estimation of the essential matrix between each camera pair using the 5-point method for intrinsically calibrated cameras. The method is compared to a manual calibration method using real HD video data from a field trial with a multicamera positioning system. The method is also evaluated on simulated data from a stereo camera model. The results show that the reprojection error of the automated camera calibration method is close to or smaller than the error for the manual calibration method and that the automated calibration method can replace the manual calibration.

The EDA project “Detection in Urban scenario using Combined Airborne imaging Sensors” (DUCAS) is in progress. The aim of the project is to investigate the potential benefit of combined high spatial and spectral resolution airborne imagery for several defense applications in the urban area. The project is taking advantage of the combined resources from 7 contributing nations within the EDA framework. An extensive field trial has been carried out in the city of Zeebrugge at the Belgian coast in June 2011. The Belgian armed forces contributed with platforms, weapons, personnel (soldiers) and logistics for the trial. Ground truth measurements with respect to geometrical characteristics, optical material properties and weather conditions were obtained in addition to hyperspectral, multispectral and high resolution spatial imagery. High spectral/spatial resolution sensor data are used for detection, classification, identification and tracking.

Stand-off THz imaging to detect concealed treats is a coming technique for security applications. A THz sensor can provide high resolution 3D imagery of a scene. However, efficient scene scanning and management of the THz sensor is a challenging task due to the limited field of view of the sensor and physical scanning limitations. In this paper we discuss the requirements on a scene scanning solution and present a scene scanning technique using a multi-camera system with 3D positioning capabilities. A visual hull method is used to position subjects in the scene. The presented technique relaxes the requirements on the scanning speed of the THz sensor and facilitates an efficient scene scanning solution.

The development of new asymmetric threats to civilian and naval ships has been a relatively recent occurrence. The bombing of the USS Cole is one example and the pirate activities outside Somalia another. There is a need to recognize targets at long ranges and possibly also their intentions to prepare for counteractions. Eye safe laser imaging at 1.5 μm offers target recognition at long ranges during day and night. The 1.5 μm wavelength is suitable for observing small targets at the sea surface such as boats and swimmers due to the low reflectivity of water compared to potential targets. Turbulence and haze limits the sensor performance and their influence is estimated for some cases of operational interest. For comparison, passive EO images have been recorded with the same camera to investigate the difference between sun illuminated and laser illuminated images. Examples of laser images will be given for a variety of targets and external conditions.Image segmentation for future automated recognition development is described and examplified. Examples of relevant 1.5 μm laser reflectivities of small naval targets are also presented. Finally a discussion of system aspects is made.