Identifying genotype specific elevated-risk areas and associated herd risk factors for bovine tuberculosis spread in British cattle
Publication date: Available online 1 March 2018 Source:Epidemics Author(s): R.J. Orton, M. Deason, P.R. Bessell, D.M. Green, R.R. Kao, L.C.M. Salvador Bovine tuberculosis (bTB) is a chronic zoonosis with major health and economic impact on the cattle industry. Despite extensive control measures in cattle and culling trials in wildlife, the reasons behind the expansion of areas with high incidence of bTB breakdowns in Great Britain remain unexplained. By balancing the importance of cattle movements and local transmission on the observed pattern of cattle outbreaks, we identify areas at elevated risk of infection fro...
Source: Epidemics - March 1, 2018 Category: Epidemiology Source Type: research
Acute illness from Campylobacter jejuni may require high doses while infection occurs at low doses
Publication date: Available online 8 February 2018 Source:Epidemics Author(s): Peter F.M. Teunis, Axel Bonačić Marinović, David R. Tribble, Chad K. Porter, Arno Swart Data from a set of different studies on the infectivity and pathogenicity of Campylobacter jejuni were analyzed with a multilevel model, allowing for effects of host species (nonhuman primates and humans) and different strains of the pathogen. All challenge studies involved high doses of the pathogen, resulting in all exposed subjects to become infected. In only one study a dose response effect (increasing trend with dose) for infection was observed...
Source: Epidemics - February 27, 2018 Category: Epidemiology Source Type: research
The distribution of district-level leprosy incidence in India is geometric-stable, consistent with subcriticality
Publication date: Available online 14 February 2018 Source:Epidemics Author(s): Thomas M. Lietman, Lee Worden, Fengchen Liu, Travis C. Porco Mathematical models predict that the community-level incidence of a controlled infectious disease across a region approaches a geometric distribution. This could hold over larger regions, if new cases remain proportional to existing cases. Leprosy has been disappearing for centuries, making an excellent candidate for testing this hypothesis. Here, we show the annual new case detection rate of leprosy in Indian districts to be consistent with a geometric distribution. For 2008-20...
Source: Epidemics - February 27, 2018 Category: Epidemiology Source Type: research
Results from the second year of a collaborative effort to forecast influenza seasons in the United States
Publication date: Available online 24 February 2018 Source:Epidemics Author(s): Matthew Biggerstaff, Michael Johansson, David Alper, Logan C. Brooks, Prithwish Chakraborty, David C. Farrow, Sangwon Hyun, Sasikiran Kandula, Craig McGowan, Naren Ramakrishnan, Roni Rosenfeld, Jeffrey Shaman, Rob Tibshirani, Ryan J. Tibshirani, Alessandro Vespignani, Wan Yang, Qian Zhang, Carrie Reed Accurate forecasts could enable more informed public health decisions. Since 2013, CDC has worked with external researchers to improve influenza forecasts by coordinating seasonal challenges for the United States and the 10 Hea...
Source: Epidemics - February 27, 2018 Category: Epidemiology Source Type: research
A Bayesian Evidence Synthesis Approach to Estimate Disease Prevalence in Hard-To-Reach Populations: Hepatitis C in New York City
Publication date: Available online 3 February 2018 Source:Epidemics Author(s): Sarah Tan, Susanna Makela, Daliah Heller, Kevin Konty, Sharon Balter, Tian Zheng, James H. Stark Existing methods to estimate the prevalence of chronic hepatitis C (HCV) in New York City (NYC) are limited in scope and fail to assess hard-to-reach subpopulations with highest risk such as injecting drug users (IDUs). To address these limitations, we employ a Bayesian multi-parameter evidence synthesis model to systematically combine multiple sources of data, account for bias in certain data sources, and provide unbiased HCV prevalence est...
Source: Epidemics - February 3, 2018 Category: Epidemiology Source Type: research
Assessing the variability in transmission of bovine tuberculosis within spanish cattle herds
Publication date: Available online 31 January 2018 Source:Epidemics Author(s): G. Ciaravino, A. García-Saenz, S. Cabras, A. Allepuz, J. Casal, I. García-Bocanegra, A. De Koeijer, S. Gubbins, J.L. Sáez, D. Cano-Terriza, S. Napp In Spain, despite years of efforts to eradicate bovine tuberculosis (bTB), the disease is still endemic, with some areas of high prevalence. In this context, the surveillance and control plans may need to be re-evaluated, and understanding the dynamics of bTB spread within Spanish herds may help to develop new strategies for reducing the time for detection of infected herds and for th...
Source: Epidemics - January 31, 2018 Category: Epidemiology Source Type: research
Modeling Marek's disease virus transmission: a framework for evaluating the impact of farming practices and evolution on disease
Publication date: Available online 10 January 2018 Source:Epidemics Author(s): David A. Kennedy, Patricia A. Dunn, Andrew F. Read Marek's disease virus (MDV) is a pathogen of chickens whose control has twice been undermined by pathogen evolution. Disease ecology is believed to be the main driver of this evolution, yet mathematical models of MDV disease ecology have never been confronted with data to test their reliability. Here, we develop a suite of MDV models that differ in the ecological mechanisms they include. We fit these models with maximum likelihood using iterated filtering in ‘pomp’ to data on MDV concen...
Source: Epidemics - January 23, 2018 Category: Epidemiology Source Type: research
Digital Dermatitis in dairy cattle: the contribution of different disease classes to transmission
Publication date: Available online 22 December 2017 Source:Epidemics Author(s): Floor Biemans, Piter Bijma, Natasja M. Boots, Mart C.M. de Jong Digital Dermatitis (DD) is a claw disease mainly affecting the hind feet of dairy cattle. Digital Dermatitis is an infectious disease, transmitted via the environment, where the infectious “agent” is a combination of bacteria. The standardized classification for DD lesions developed by Döpfer et al. (1997) and extended by Berry et al. (2012) has six distinct classes: healthy (M0), an active granulomatous area of 0–2 cm (M1), an ulcerative lesion of >2 cm (M2...
Source: Epidemics - December 22, 2017 Category: Epidemiology Source Type: research
epidemix —An interactive multi-model application for teaching and visualizing infectious disease transmission
Publication date: Available online 11 December 2017 Source:Epidemics Author(s): Ulrich Muellner, Guillaume Fournié, Petra Muellner, Christina Ahlstrom, Dirk U. Pfeiffer Mathematical models of disease transmission are used to improve our understanding of patterns of infection and to identify factors influencing them. During recent public and animal health crises, such as pandemic influenza, Ebola, Zika, foot-and-mouth disease, models have made important contributions in addressing policy questions, especially through the assessment of the trajectory and scale of outbreaks, and the evaluation of control interventions...
Source: Epidemics - December 20, 2017 Category: Epidemiology Source Type: research
The importance of being urgent: the impact of surveillance target and scale on mosquito-borne disease control
Publication date: Available online 16 December 2017 Source:Epidemics Author(s): Samantha R. Schwab, Chris M. Stone, Dina M. Fonseca, Nina H. Fefferman With the emergence or re-emergence of numerous mosquito-borne diseases in recent years, effective methods for emergency vector control responses are necessary to reduce human infections. Current vector control practices often vary significantly between different jurisdictions, and are executed independently and at different spatial scales. Various types of surveillance information (e.g. number of human infections or adult mosquitoes) trigger the implementation of contr...
Source: Epidemics - December 16, 2017 Category: Epidemiology Source Type: research
Species interactions may help explain the erratic periodicity of whooping cough dynamics
Publication date: Available online 14 December 2017 Source:Epidemics Author(s): Samit Bhattacharyya, Matthew J. Ferrari, Ottar N. Bjørnstad Incidence of whooping cough exhibits variable dynamics across time and space. The periodicity of this disease varies from annual to five years in different geographic regions in both developing and developed countries. Many hypotheses have been put forward to explain this variability such as nonlinearity and seasonality, stochasticity, variable recruitment of susceptible individuals via birth, immunization, and immune boosting. We propose an alternative hypothesis to describe the...
Source: Epidemics - December 15, 2017 Category: Epidemiology Source Type: research
Contact Tracing for the Control of Infectious Disease Epidemics: Chronic Wasting Disease in Deer Farms
Publication date: Available online 14 December 2017 Source:Epidemics Author(s): Chris Rorres, Maria Romano, Jennifer A. Miller, Jana M. Mossey, Anthony H. Grubesic, David E. Zellner, Gary Smith Contact tracing is a crucial component of the control of many infectious diseases, but is an arduous and time consuming process. Procedures that increase the efficiency of contact tracing increase the chance that effective controls can be implemented sooner and thus reduce the magnitude of the epidemic. We illustrate a procedure using Graph Theory in the context of infectious disease epidemics of farmed animals in which the...
Source: Epidemics - December 15, 2017 Category: Epidemiology Source Type: research
Epidemix – an Interactive Multi-Model Application for Teaching and Visualizing Infectious Disease Transmission
Publication date: Available online 11 December 2017 Source:Epidemics Author(s): Ulrich Muellner, Guillaume Fournié, Petra Muellner, Christina Ahlstrom, Dirk U. Pfeiffer Mathematical models of disease transmission are used to improve our understanding of patterns of infection and to identify factors influencing them. During recent public and animal health crises, such as pandemic influenza, Ebola, Zika, foot-and-mouth disease, models have made important contributions in addressing policy questions, especially through the assessment of the trajectory and scale of outbreaks, and the evaluation of control interventions...
Source: Epidemics - December 12, 2017 Category: Epidemiology Source Type: research
An infectious way to teach students about outbreaks
Publication date: Available online 9 December 2017 Source:Epidemics Author(s): Íde Cremin, Oliver Watson, Alastair Heffernan, Natsuko Imai, Norin Ahmed, Sandra Bivegete, Teresia Kimani, Demetris Kyriacou, Preveina Mahadevan, Rima Mustafa, Panagiota Pagoni, Marisa Sophiea, Charlie Whittaker, Leo Beacroft, Steven Riley, Matthew C. Fisher The study of infectious disease outbreaks is required to train today’s epidemiologists. A typical way to introduce and explain key epidemiological concepts is through the analysis of a historical outbreak. There are, however, few training options that explicitly utilise ...
Source: Epidemics - December 10, 2017 Category: Epidemiology Source Type: research
Modeling HIV disease progression and transmission at population-level: The potential impact of modifying disease progression in HIV treatment programs
Conclusion Even when compared with valacyclovir suppression, a drug that reduces HIV viral load, universal treatment for HIV is the optimal strategy for averting new infections and increasing public health benefit. Universal HIV treatment would most effectively and efficiently reduce the HIV burden. (Source: Epidemics)
Source: Epidemics - December 6, 2017 Category: Epidemiology Source Type: research
