Serologic Screening for Genital Herpes: An Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

Importance: Genital herpes simplex virus (HSV) infection is a prevalent sexually transmitted infection. Vertical transmission of HSV can lead to fetal morbidity and mortality. Objective: To assess the evidence on serologic screening and preventive interventions for genital HSV infection in asymptomatic adults and adolescents to support the US Preventive Services Task Force for an updated recommendation statement. Data Sources: MEDLINE, Cochrane Library, EMBASE, and trial registries through March 31, 2016. Surveillance for new evidence in targeted publications was conducted through October 31, 2016. Study Selection: English-language randomized clinical trials (RCTs) comparing screening with no screening in persons without past or current symptoms of genital herpes; studies evaluating accuracy and harms of serologic screening tests for HSV-2; RCTs assessing preventive interventions in asymptomatic persons seropositive for HSV-2. Data Extraction and Synthesis: Dual review of abstracts, full-text articles, and study quality; pooled sensitivities and specificities of screening tests using a hierarchical summary receiver operating characteristic curve analysis when at least 3 similar studies were available. Main Outcomes and Measures: Accuracy of screening tests, benefits of screening, harms of screening, reduction in genital herpes outbreaks. Results: A total of 17 studies (n = 9736 participants; range, 24-3290) in 19 publications were included. No RCTs compared screening with no screening. Most studies of the accuracy of screening tests were from populations with high HSV-2 prevalence (greater than 40% based on Western blot). Pooled estimates of sensitivity and specificity of the most commonly used test at the manufacturer's cutpoint were 99% (95% CI, 97%-100%) and 81% (95% CI, 68%-90%), respectively (10 studies; n = 6537). At higher cutpoints, pooled estimates were 95% (95% CI, 91%-97%) and 89% (95% CI, 82%-93%), respectively (7 studies; n = 5516). Use of this test at the manufacturer's cutpoint in a population of 100 000 with a prevalence of HSV-2 of 16% (the seroprevalence in US adults with unknown symptom status) would result in 15 840 true-positive results and 15 960 false-positive results (positive predictive value, 50%). Serologic screening for genital herpes was associated with psychosocial harms, including distress and anxiety related to positive test results. Four RCTs compared preventive medications with placebo, 2 in nonpregnant asymptomatic adults who were HSV-2 seropositive and 2 in HSV-2-serodiscordant couples. Results in both populations were heterogeneous and inconsistent. Conclusions and Relevance: Serologic screening for genital herpes is associated with a high rate of false-positive test results and potential psychosocial harms. Evidence from RCTs does not establish whether preventive antiviral medication for asymptomatic HSV-2 infection has benefit

High-Temperature Oxidation of a High Silicon SiMo Spheroidal Cast Iron in Air with <i>In Situ</i> Change in H₂O Content

Exhaust manifolds for diesel engines are made of high-Si ferritic nodular cast irons. It is experimentally well established that their oxidation kinetics are highly sensitive to the presence of water vapor, though the mechanism for such an effect is still controversial. In the present work, isothermal oxidation tests were performed on a SiMo nodular cast iron at 700 °C and 800 °C in dry and humid air for 25 and 50 hours. Other samples were oxidized for 50 h with in-situ change in H2O content after 25 h, switching from dry air to humid air or the other way around. Samples were then analyzed using XRD, SEM-EDS and Raman spectroscopy. Thermogravimetric records clearly showed the effect of temperature and environment on oxidation and decarburization. The kinetics of these phenomena depend on silica formation at the metal-oxide interface. At both temperatures,water vapor was seen to promote internal oxidation of Si instead of its external oxidation. This leads to higher oxidation rate at 700°C and higher decarburization rate at 800 °C

Genetic Variability of West Nile Virus in US Blood Donors, 2002–2005

This virus is diverging from precursor isolates as its geographic distribution expands

Widespread extrahippocampal NAA/(Cr+Cho) abnormalities in TLE with and without mesial temporal sclerosis

MR spectroscopy has demonstrated extrahippocampal NAA/(Cr+Cho) reductions in medial temporal lobe epilepsy with (TLE-MTS) and without (TLE-no) mesial temporal sclerosis. Because of the limited brain coverage of those previous studies, it was, however, not possible to assess differences in the distribution and extent of these abnormalities between TLE-MTS and TLE-no. This study used a 3D whole brain echoplanar spectroscopic imaging (EPSI) sequence to address the following questions: (1) Do TLE-MTS and TLE-no differ regarding severity and distribution of extrahippocampal NAA/(Cr+Cho) reductions? (2) Do extrahippocampal NAA/(Cr+Cho) reductions provide additional information for focus lateralization? Forty-three subjects (12 TLE-MTS, 13 TLE-no, 18 controls) were studied with 3D EPSI. Statistical parametric mapping (SPM2) was used to identify regions of significantly decreased NAA/(Cr+Cho) in TLE groups and in individual patients. TLE-MTS and TLE-no had widespread extrahippocampal NAA/(Cr+Cho) reductions. NAA/(Cr+Cho) reductions had a bilateral fronto-temporal distribution in TLE-MTS and a more diffuse, less well defined distribution in TLE-no. Extrahippocampal NAA/(Cr+Cho) decreases in the single subject analysis showed a large inter-individual variability and did not provide additional focus lateralizing information. Extrahippocampal NAA/(Cr+Cho) reductions in TLE-MTS and TLE-no are neither focal nor homogeneous. This reduces their value for focus lateralization and suggests a heterogeneous etiology of extrahippocampal spectroscopic metabolic abnormalities in TLE

Multiple sources of Escherichia coli O157

Abstract Samples from cattle, other domestic and wild animals, flies, feeds, and water-troughs were collected from 12 cattle farms and tested for Escherichia coli O157. E. coli O157 was isolated from bovine fecal samples on all 12 farms with a within herd prevalence ranging from 1.1% to Ž . Ž . 6.1%. E. coli O157 was also found in 1 of 90 1.1% equine fecal samples, 2 of 65 3.1% canine Ž . Ž . fecal samples, 1 of 200 pooled bird samples 0.5% , 2 of 60 pooled fly samples 3.3% , and 10 of Ž . Ž . 320 3.1% water-trough sample sets biofilm and water . No E. coli O157 were isolated from 300 rodents, 33 cats, 34 assorted wildlife, or 335 cattle feed samples. Indistinguishable pulsed-field gel electrophoresis patterns of XbaI digested chromosomal DNA and Shiga toxin types were observed for bovine and water-trough isolates from two farms and for one equine and two bovine isolates from one farm. q 1998 Elsevier Science B.V

Absolute Doubly Differential Angular Sputtering Yields for 20 keV Kr+ on Polycrystalline Cu

We have measured the absolute doubly differential angular sputtering yield for 20 keV Kr+ impacting a polycrystalline Cu slab at an incidence angle of {\theta}i = 45{\deg} relative to the surface normal. Sputtered Cu atoms were captured using collectors mounted on a half dome above the sample, and the sputtering distribution was measured as a function of the sputtering polar, {\theta}s, and azimuthal, phi, angles. Absolute results of the sputtering yield were determined from the mass gain of each collector, the ion dose, and the solid angle subtended, after irradiation to a total fluence of ~ 1 x 10^18 ions/cm^2. Our approach overcomes shortcomings of commonly used methods that only provide relative yields as a function of {\theta}s in the incidence plane (defined by the ion velocity and the surface normal). Our experimental results display an azimuthal variation that increases with increasing {\theta}s and is clearly discrepant with simulations using binary collision theory. We attribute the observed azimuthal anisotropy to ion-induced formation of micro- and nano-scale surface features that suppress the sputtering yield through shadowing and redeposition effects, neither of which are accounted for in the simulations. Our experimental results demonstrate the importance of doubly differential angular sputtering studies to probe ion sputtering processes at a fundamental level and to explore the effect of ion-beam-generated surface roughness.Comment: 29 pages, 9 figure