18 research outputs found

    Cell-phone traces reveal infection-associated behavioral change

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    To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadEpidemic preparedness depends on our ability to predict the trajectory of an epidemic and the human behavior that drives spread in the event of an outbreak. Changes to behavior during an outbreak limit the reliability of syndromic surveillance using large-scale data sources, such as online social media or search behavior, which could otherwise supplement healthcare-based outbreak-prediction methods. Here, we measure behavior change reflected in mobile-phone call-detail records (CDRs), a source of passively collected real-time behavioral information, using an anonymously linked dataset of cell-phone users and their date of influenza-like illness diagnosis during the 2009 H1N1v pandemic. We demonstrate that mobile-phone use during illness differs measurably from routine behavior: Diagnosed individuals exhibit less movement than normal (1.1 to 1.4 fewer unique tower locations; [Formula: see text]), on average, in the 2 to 4 d around diagnosis and place fewer calls (2.3 to 3.3 fewer calls; [Formula: see text]) while spending longer on the phone (41- to 66-s average increase; [Formula: see text]) than usual on the day following diagnosis. The results suggest that anonymously linked CDRs and health data may be sufficiently granular to augment epidemic surveillance efforts and that infectious disease-modeling efforts lacking explicit behavior-change mechanisms need to be revisited. Keywords: call detail records; disease; influenza; outbreak; surveillance.Alan Turing Institute Engineering and Physical Sciences Research Council EP/N510129/1 UK Research & Innovation (UKRI) Medical Research Council UK (MRC) European Commission National Institute for Health Research (NIHR) Health Protection Research Unit in Evaluation of Interventions at the University of Brist

    Trends in HIV surveillance data in the EU/EEA, 2005 to 2014: New HIV diagnoses still increasing in men who have sex with men

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    Human immunodeficiency virus (HIV) transmission remains significant in Europe. Rates of acquired immunodeficiency syndrome (AIDS) have declined, but not in all countries. New HIV diagnoses have increased among native and foreign-born men who have sex with men. Median CD4+T-cell count at diagnosis has increased, but not in all groups, and late diagnosis remains common. HIV infection and AIDS can be eliminated in Europe with resolute prevention measures, early diagnosis and access to effective treatment

    Molecular benchmarks of a SARS-CoV-2 epidemic.

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    To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadA pressing concern in the SARS-CoV-2 epidemic and other viral outbreaks, is the extent to which the containment measures are halting the viral spread. A straightforward way to assess this is to tally the active cases and the recovered ones throughout the epidemic. Here, we show how epidemic control can be assessed with molecular information during a well characterized epidemic in Iceland. We demonstrate how the viral concentration decreased in those newly diagnosed as the epidemic transitioned from exponential growth phase to containment phase. The viral concentration in the cases identified in population screening decreased faster than in those symptomatic and considered at high risk and that were targeted by the healthcare system. The viral concentration persists in recovering individuals as we found that half of the cases are still positive after two weeks. We demonstrate that accumulation of mutations in SARS-CoV-2 genome can be exploited to track the rate of new viral generations throughout the different phases of the epidemic, where the accumulation of mutations decreases as the transmission rate decreases in the containment phase. Overall, the molecular signatures of SARS-CoV-2 infections contain valuable epidemiological information that can be used to assess the effectiveness of containment measures

    D-arabinitol in the diagnosis of invasive candidiasis

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    Invasive candidiasis (IC) is a serious condition and timely diagnosis with early initiation of antifungal therapy is imerative for improving outcomes. Arabinitol is a sugar alcohol with two stereoisomers, D-arabinitol (DA) and L-arabintiol (LA). Several pathogenic Candida species produce DA in vitro and high DA levels have been detected in serum and urine in patients with IC. Renal dysfunction affects serum DA levels, serum and urine DA/LA or serum DA/creatinine are therefore measured to correct for kidney dysfunction. DA/LA ratio in urine was examined in neonatal infants in Lund, in patients with hematologic malignancies in Brisbane, Australia, and in HIV patients. Urine samples were collected on filter paper, which was found easy to apply and facilitated shipment of samples. DA/LA ratio is a reliable diagnostic method of IC in neonatal infants, all six infants with IC had elevated DA/LA ratios. Additionally five of eight infants receiving empirical antifungal treatment had elevated DA/LA ratios. The DA/LA ratio had lower sensitivity in hematology patients in Australia probably reflecting local changes in the epidemiology of candidemia with increased proportion of fungemias caused by C. krusei. HIV patients had normal DA/LA ratios and elevated ratios were not detected in five patients with Candida esophagitis. Clinical usage of DA/LA ratio in urine was studied iat the pediatric oncology unit (POU) and at the neonatal intensive care unit (NICU) in Lund. Screening of neutropenic children with cancer at the POU was found to decrease the number of IC but at the NICU the number of IC remained unchanged where the DA/LA ration was obtained only when IC was suspected. In vitro studies on DA production showed DA production in C. dubliniensis and C. krusei although C. krusei was found to produce low levels of DA. Neither in vitro nor in vivo DA production was detected in C. glabrata. DA production rate was highest in C. albicans and both intra and inter species variation of in vitro DA production was observed, which warrants further studies on the DA production rate and the sensitivity of DA/LA ratio in clinical use

    D-arabinitol--a marker for invasive candidiasis

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    The five-carbon sugar alcohol D-arabinitol (DA) is a metabolite of most pathogenic Candida species, in vitro as well as in vivo, and can be determined by gas chromatography or enzymatic analysis. Endogenous DA and L-arabinitol (LA) are present in human body fluids, and serum DA and LA increase in renal dysfunction. In prospective clinical studies, elevated DA/LA or DA/creatine ratios in serum or urine have been found in immunocompromised, usually neutropenic, patients with invasive candidiasis. In addition, positive DA results have been obtained several days to weeks before positive blood cultures, and the normalization of DA levels has been correlated with therapeutic response in both humans and animals. However, to date, only a few prospective studies have been conducted in which adequate analytical methods were used. Thus, further investigation of various patient groups is needed to establish the applicability of the 'arabinitol method' in the diagnostic battery for invasive Candida infections

    To Alfred Deakin

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    To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldIn 2 prospective studies, we previously reported on the early and accurate diagnosis of invasive candidiasis by determining the D-arabinitol/L-arabinitol (DA/LA) ratio in urine in neutropenic children with cancer at the paediatric oncology unit (POU) and in premature infants at the neonatal intensive care unit (NICU) at our hospital. In this retrospective study at the same units, we report how the DA/LA assay was implemented in clinical practice immediately after the prospective study periods. We found that, in the POU, the recommendation of regularly monitoring urine DA/LA ratios in patients at risk and considering antifungal therapy in the case of elevated ratios had been followed. A significant decrease in the incidence of culture positive invasive candidiasis may have been attributed to the introduction of the DA/LA assay. At the NICU, where the DA/LA assay was recommended only as an adjunct to other diagnostic tools, morbidity in invasive candidiasis remained unchanged. While regular monitoring of the urine DA/LA ratio probably facilitates the early detection of invasive candidiasis in paediatric oncology, it remains to be determined if the test can be used in a similar way in neonatal intensive care
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