The role of fomites in infectious disease transmission relative to other exposure routes is difficult to discern due, in part, to the lack of information on the level and distribution of virus contamination on surfaces. Comparisons of studies intending to fill this gap are difficult because multiple different sampling methods are employed and authors rarely report their method's lower limit of detection. In the present study, we compare a subset of sampling methods identified from a literature review to demonstrate that sampling method significantly influences study outcomes. We then compare a subset of methods identified from the review to determine the most efficient methods for recovering virus from surfaces in a laboratory trial using MS2 bacteriophage as a model virus. Recoveries of infective MS2 and MS2 RNA are determined using both a plaque assay and quantitative reverse transcription-PCR, respectively. We conclude that the method that most effectively recovers virus from nonporous fomites uses polyester-tipped swabs prewetted in either one-quarterstrength Ringer's solution or saline solution. This method recovers a median fraction for infective MS2 of 0.40 and for MS2 RNA of 0.07. Use of the proposed method for virus recovery in future fomite sampling studies would provide opportunities to compare findings across multiple studies.Preclusion of infection is the most effective method to combat the respiratory and gastrointestinal diseases that cause over 6 million annual deaths worldwide (12, 59). Successful interventions to reduce disease burden include hand and environmental hygiene (9, 76), but the impact of these interventions is difficult to quantify, as the importance of contact with contaminated surfaces, or fomites, relative to other transmission routes is uncertain (17,62).Evidence of the importance of fomites comes from both laboratory and field studies. Laboratory studies have demonstrated that the handling of either artificially or naturally contaminated fomites by susceptible hosts indoors results in subsequent infection (41, 43). Additionally, virus can be transferred between hands and fomites on contact and survive on fomites for hours or days (1,8,72). As such, it is not surprising that fomites, such as carpets (29, 65), towels, and medication cart items (60) have been implicated as the primary cause of multiple outbreaks. Environmental hygiene intended to mitigate fomite-mediated transmission has been shown to significantly reduce illness-related absences in classrooms (18). Despite this evidence, questions remain regarding both the efficacy of fomite-mediated transmission relative to other exposure routes (5, 46) and the likelihood of virus transfer from fomites to hosts (66).To better understand the role of fomites in disease transmission, characterization of the level and distribution of virus on surfaces is required. Surface contamination is most often described by the positivity rate, defined as the fraction of total samples collected on which the organism is detectable (19). However,...

Aim: to determine the safety of simple laparoscopic cholecystectomy in ageing patients. Method: the outcome of patients between 60 and 70 years of age and patients over 70 who underwent laparoscopic cholecystectomy for symptomatic non-malignant gallbladder disease was comparatively analysed. All patients over 60 years of age with symptomatic gallbladder disease and without cholecholithiasis, septic shock, diffuse peritonitis, gallbladder malignancy, portal hypertension or contraindication for general anaesthesia were selected for simple laparoscopic cholecystectomy (n = 158). This group represents over 80% of all elderly patients undergoing biliary surgery at our department over this period. Group A (n = 97) included patients from 60 to 69 years of age. Group B (n -61) comprised patients over 70 years. Results: there was no difference in sex distribution between groups. Operative time and conversion rates were similar in both groups. The overall morbidity rate was 14.5%, with no statistically significant increase in group B (11% for group Avs20% for group B). No perioperative mortality occurred. Recurrent biliary surgery was required in two patients from group B (3%). Postoperative endoscopic retrograde cholangiography and sphincterotomy was done in four patients from group A (4%). The mean postoperative stay was longer for older patients (group A, 3.1 (2.5) days; group B, 4.2 (4.3) days; i>=0.05). Conclusion: simple laparoscopic cholecystectomy is safe in the aged, even for patients over 70. This procedure is associated with a short hospital stay and low rates of re-admission and recurrent biliary surgery.

We present the results from four stellar occultations by (486958) Arrokoth, the flyby target of the New Horizons extended mission. Three of the four efforts led to positive detections of the body, and all constrained the presence of rings and other debris, finding none. Twenty-five mobile stations were deployed for 2017 June 3 and augmented by fixed telescopes. There were no positive detections from this effort. The event on 2017 July 10 was observed by SOFIA with one very short chord. Twenty-four deployed stations on 2017 July 17 resulted in five chords that clearly showed a complicated shape consistent with a contact binary with rough dimensions of 20 by 30 km for the overall outline. A visible albedo of 10% was derived from these data. Twenty-two systems were deployed for the fourth event on 2018 Aug 4 and resulted in two chords. The combination of the occultation data and the flyby results provides a significant refinement of the rotation period, now estimated to be 15.9380 ± 0.0005 hours. The occultation data also provided high-precision astrometric constraints on the position of the object that were crucial for supporting the navigation for the New Horizons flyby. This work demonstrates an effective method for obtaining detailed size and shape information and probing for rings and dust on distant Kuiper Belt objects as well as being an important source of positional data that can aid in spacecraft navigation that is particularly useful for small and distant bodies.

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Laparoscopic abdominal surgery is considered a low-risk procedure for postoperative thromboembolic disease. We report two cases of pulmonary embolism following laparoscopic cholecystectomy, review the incidence of deep venous thrombosis and pulmonary embolism in laparoscopic cholecystectomy, and suggest a specific prophylactic scheme for patients undergoing laparoscopic cholecystectomy. In spite of the low incidence of postoperative thromboembolic disease following minimally invasive procedures, the risk of pulmonary embolism must not be underestimated and its symptoms must not be underdiagnosed.