journal
MENU ▼
Read by QxMD icon Read
search

Epidemics

journal
https://www.readbyqxmd.com/read/28416219/displacement-of-sexual-partnerships-in-trials-of-sexual-behavior-interventions-a-model-based-assessment-of-consequences
#1
Alethea W McCormick, Nadia N Abuelezam, Thomas Fussell, George R Seage, Marc Lipsitch
We investigated the impact of the displacement of sexual activity from adherent recipients of an intervention to others within or outside a trial population on the results from hypothetical trials of different sexual behavior interventions. A short-term model of HIV-prevention interventions that lead to female rejection of male partnership requests showed the impact of displacement expected at the start of a trial. An agent-based model, with sexual mixing and other South African specific demographics, evaluated consequences of displacement for sexual behavior interventions targeting young females in South Africa...
April 2, 2017: Epidemics
https://www.readbyqxmd.com/read/28359662/assessing-the-transmission-dynamics-of-measles-in-japan-2016
#2
Hiroshi Nishiura, Kenji Mizumoto, Yusuke Asai
OBJECTIVES: Despite the verification of measles elimination, Japan experienced multiple generations of measles transmission following importation events in 2016. The purpose of the present study was to analyze the transmission dynamics of measles in Japan, 2016, estimating the transmission potential in the partially vaccinated population. METHODS: All diagnosed measles cases were notified to the government, and the present study analyzed two pieces of datasets independently, i...
March 22, 2017: Epidemics
https://www.readbyqxmd.com/read/28351673/elucidating-transmission-dynamics-and-host-parasite-vector-relationships-for-rodent-borne-bartonella-spp-in-madagascar
#3
Cara E Brook, Ying Bai, Emily O Yu, Hafaliana C Ranaivoson, Haewon Shin, Andrew P Dobson, C Jessica E Metcalf, Michael Y Kosoy, Katharina Dittmar
Bartonella spp. are erythrocytic bacteria transmitted via arthropod vectors, which infect a broad range of vertebrate hosts, including humans. We investigated transmission dynamics and host-parasite-vector relationships for potentially zoonotic Bartonella spp. in invasive Rattus rattus hosts and associated arthropod ectoparasites in Madagascar. We identified five distinct species of Bartonella (B. elizabethae 1, B. elizabethae 2, B. phoceensis 1, B. rattimassiliensis 1, and B. tribocorum 1) infecting R. rattus rodents and their ectoparasites...
March 16, 2017: Epidemics
https://www.readbyqxmd.com/read/28395850/the-impact-of-stratified-immunity-on-the-transmission-dynamics-of-influenza
#4
Hsiang-Yu Yuan, Marc Baguelin, Kin O Kwok, Nimalan Arinaminpathy, Edwin van Leeuwen, Steven Riley
Although empirical studies show that protection against influenza infection in humans is closely related to antibody titres, influenza epidemics are often described under the assumption that individuals are either susceptible or not. Here we develop a model in which antibody titre classes are enumerated explicitly and mapped onto a variable scale of susceptibility in different age groups. Fitting only with pre- and post-wave serological data during 2009 pandemic in Hong Kong, we demonstrate that with stratified immunity, the timing and the magnitude of the epidemic dynamics can be reconstructed more accurately than is possible with binary seropositivity data...
March 12, 2017: Epidemics
https://www.readbyqxmd.com/read/28365331/on-the-duration-of-the-period-between-exposure-to-hiv-and-detectable-infection
#5
Bernhard P Konrad, Darlene Taylor, Jessica M Conway, Gina S Ogilvie, Daniel Coombs
HIV infection cannot be detected immediately after exposure because plasma viral loads are too small initially. The duration of this phase of infection (the "eclipse period") is difficult to estimate because precise dates of exposure are rarely known. Therefore, the reliability of clinical HIV testing during the first few weeks of infection is unknown, creating anxiety among HIV-exposed individuals and their physicians. We address this by fitting stochastic models of early HIV infection to detailed viral load records for 78 plasma donors, taken during the period of exposure and infection...
March 11, 2017: Epidemics
https://www.readbyqxmd.com/read/28431862/application-of-the-cdc-ebolaresponse-modeling-tool-to-disease-predictions
#6
Robert H Gaffey, Cécile Viboud
Model-based predictions were critical in eliciting a vigorous international public health response to the 2014 Ebola Virus Disease outbreak in West Africa. Here, we describe the performances of an extension of the CDC-initiated EbolaResponse Modeling tool to the Ebola Forecasting Challenge, which offered a controlled environment for epidemiological predictions. In the EbolaResponse tool, transmission risks and proportions of population affected by interventions were fitted to data via least square fitting. Prediction performances were evaluated for 5 prediction time points of 4 synthetic outbreaks...
March 10, 2017: Epidemics
https://www.readbyqxmd.com/read/28283373/dynamics-affecting-the-risk-of-silent-circulation-when-oral-polio-vaccination-is-stopped
#7
J S Koopman, C J Henry, J H Park, M C Eisenberg, E L Ionides, J N Eisenberg
Waning immunity could allow transmission of polioviruses without causing poliomyelitis by promoting silent circulation (SC). Undetected SC when oral polio vaccine (OPV) use is stopped could cause difficult to control epidemics. Little is known about waning. To develop theory about what generates SC, we modeled a range of waning patterns. We varied both OPV and wild polio virus (WPV) transmissibility, the time from beginning vaccination to reaching low polio levels, and the infection to paralysis ratio (IPR)...
March 1, 2017: Epidemics
https://www.readbyqxmd.com/read/28342787/forecasting-ebola-with-a-regression-transmission-model
#8
Jason Asher
We describe a relatively simple stochastic model of Ebola transmission that was used to produce forecasts with the lowest mean absolute error among Ebola Forecasting Challenge participants. The model enabled prediction of peak incidence, the timing of this peak, and final size of the outbreak. The underlying discrete-time compartmental model used a time-varying reproductive rate modeled as a multiplicative random walk driven by the number of infectious individuals. This structure generalizes traditional Susceptible-Infected-Recovered (SIR) disease modeling approaches and allows for the flexible consideration of outbreaks with complex trajectories of disease dynamics...
February 27, 2017: Epidemics
https://www.readbyqxmd.com/read/28351674/a-simple-approach-to-measure-transmissibility-and-forecast-incidence
#9
Pierre Nouvellet, Anne Cori, Tini Garske, Isobel M Blake, Ilaria Dorigatti, Wes Hinsley, Thibaut Jombart, Harriet L Mills, Gemma Nedjati-Gilani, Maria D Van Kerkhove, Christophe Fraser, Christl A Donnelly, Neil M Ferguson, Steven Riley
Outbreaks of novel pathogens such as SARS, pandemic influenza and Ebola require substantial investments in reactive interventions, with consequent implementation plans sometimes revised on a weekly basis. Therefore, short-term forecasts of incidence are often of high priority. In light of the recent Ebola epidemic in West Africa, a forecasting exercise was convened by a network of infectious disease modellers. The challenge was to forecast unseen "future" simulated data for four different scenarios at five different time points...
February 24, 2017: Epidemics
https://www.readbyqxmd.com/read/28325495/two-approaches-to-forecast-ebola-synthetic-epidemics
#10
David Champredon, Michael Li, Benjamin M Bolker, Jonathan Dushoff
We use two modelling approaches to forecast synthetic Ebola epidemics in the context of the RAPIDD Ebola Forecasting Challenge. The first approach is a standard stochastic compartmental model that aims to forecast incidence, hospitalization and deaths among both the general population and health care workers. The second is a model based on the renewal equation with latent variables that forecasts incidence in the whole population only. We describe fitting and forecasting procedures for each model and discuss their advantages and drawbacks...
February 24, 2017: Epidemics
https://www.readbyqxmd.com/read/28256420/using-data-driven-agent-based-models-for-forecasting-emerging-infectious-diseases
#11
Srinivasan Venkatramanan, Bryan Lewis, Jiangzhuo Chen, Dave Higdon, Anil Vullikanti, Madhav Marathe
Producing timely, well-informed and reliable forecasts for an ongoing epidemic of an emerging infectious disease is a huge challenge. Epidemiologists and policy makers have to deal with poor data quality, limited understanding of the disease dynamics, rapidly changing social environment and the uncertainty on effects of various interventions in place. Under this setting, detailed computational models provide a comprehensive framework for integrating diverse data sources into a well-defined model of disease dynamics and social behavior, potentially leading to better understanding and actions...
February 22, 2017: Epidemics
https://www.readbyqxmd.com/read/28325494/modelling-h5n1-in-bangladesh-across-spatial-scales-model-complexity-and-zoonotic-transmission-risk
#12
Edward M Hill, Thomas House, Madhur S Dhingra, Wantanee Kalpravidh, Subhash Morzaria, Muzaffar G Osmani, Mat Yamage, Xiangming Xiao, Marius Gilbert, Michael J Tildesley
Highly pathogenic avian influenza H5N1 remains a persistent public health threat, capable of causing infection in humans with a high mortality rate while simultaneously negatively impacting the livestock industry. A central question is to determine regions that are likely sources of newly emerging influenza strains with pandemic causing potential. A suitable candidate is Bangladesh, being one of the most densely populated countries in the world and having an intensifying farming system. It is therefore vital to establish the key factors, specific to Bangladesh, that enable both continued transmission within poultry and spillover across the human-animal interface...
February 21, 2017: Epidemics
https://www.readbyqxmd.com/read/28262588/population-effect-of-influenza-vaccination-under-co-circulation-of-non-vaccine-variants-and-the-case-for-a-bivalent-a-h3n2-vaccine-component
#13
Colin J Worby, Jacco Wallinga, Marc Lipsitch, Edward Goldstein
Some past epidemics of different influenza subtypes (particularly A/H3N2) in the US saw co-circulation of vaccine-type and variant strains. There is evidence that natural infection with one influenza subtype offers short-term protection against infection with another influenza subtype (henceforth, cross-immunity). This suggests that such cross-immunity for strains within a subtype is expected to be strong. Therefore, while vaccination effective against one strain may reduce transmission of that strain, this may also lead to a reduction of the vaccine-type strain's ability to suppress spread of a variant strain...
February 21, 2017: Epidemics
https://www.readbyqxmd.com/read/28279460/forecasting-the-new-case-detection-rate-of-leprosy-in-four-states-of-brazil-a-comparison-of-modelling-approaches
#14
David J Blok, Ronald E Crump, Ram Sundaresh, Martial Ndeffo-Mbah, Alison P Galvani, Travis C Porco, Sake J de Vlas, Graham F Medley, Jan Hendrik Richardus
BACKGROUND: Brazil has the second highest annual number of new leprosy cases. The aim of this study is to formally compare predictions of future new case detection rate (NCDR) trends and the annual probability of NCDR falling below 10/100,000 of four different modelling approaches in four states of Brazil: Rio Grande do Norte, Amazonas, Ceará, Tocantins. METHODS: A linear mixed model, a back-calculation approach, a deterministic compartmental model and an individual-based model were used...
March 2017: Epidemics
https://www.readbyqxmd.com/read/28279459/comparison-and-validation-of-two-computational-models-of-chagas-disease-a-thirty-year-perspective-from-venezuela
#15
Sarah M Bartsch, Jennifer K Peterson, Daniel L Hertenstein, Laura Skrip, Martial Ndeffo-Mbah, Alison P Galvani, Andrew P Dobson, Bruce Y Lee
BACKGROUND: Mathematical models can help aid public health responses to Chagas disease. Models are typically developed to fulfill a particular need, and comparing outputs from different models addressing the same question can help identify the strengths and weaknesses of the models in answering particular questions, such as those for achieving the 2020 goals for Chagas disease. METHODS: Using two separately developed models (PHICOR/CIDMA model and Princeton model), we simulated dynamics for domestic transmission of Trypanosoma cruzi (T...
March 2017: Epidemics
https://www.readbyqxmd.com/read/28279458/elimination-of-visceral-leishmaniasis-in-the-indian-subcontinent-a-comparison-of-predictions-from-three-transmission-models
#16
Epke A Le Rutte, Lloyd A C Chapman, Luc E Coffeng, Sarah Jervis, Epco C Hasker, Shweta Dwivedi, Morchan Karthick, Aritra Das, Tanmay Mahapatra, Indrajit Chaudhuri, Marleen C Boelaert, Graham F Medley, Sridhar Srikantiah, T Deirdre Hollingsworth, Sake J de Vlas
We present three transmission models of visceral leishmaniasis (VL) in the Indian subcontinent (ISC) with structural differences regarding the disease stage that provides the main contribution to transmission, including models with a prominent role of asymptomatic infection, and fit them to recent case data from 8 endemic districts in Bihar, India. Following a geographical cross-validation of the models, we compare their predictions for achieving the WHO VL elimination targets with ongoing treatment and vector control strategies...
March 2017: Epidemics
https://www.readbyqxmd.com/read/28279457/measuring-and-modelling-the-effects-of-systematic-non-adherence-to-mass-drug-administration
#17
Louise Dyson, Wilma A Stolk, Sam H Farrell, T Déirdre Hollingsworth
It is well understood that the success or failure of a mass drug administration campaign critically depends on the level of coverage achieved. To that end coverage levels are often closely scrutinised during campaigns and the response to underperforming campaigns is to attempt to improve coverage. Modelling work has indicated, however, that the quality of the coverage achieved may also have a significant impact on the outcome. If the coverage achieved is likely to miss similar people every round then this can have a serious detrimental effect on the campaign outcome...
March 2017: Epidemics
https://www.readbyqxmd.com/read/28279456/probabilistic-forecasts-of-trachoma-transmission-at-the-district-level-a-statistical-model-comparison
#18
Amy Pinsent, Fengchen Liu, Michael Deiner, Paul Emerson, Ana Bhaktiari, Travis C Porco, Thomas Lietman, Manoj Gambhir
The World Health Organization and its partners are aiming to eliminate trachoma as a public health problem by 2020. In this study, we compare forecasts of TF prevalence in 2011 for 7 different statistical and mechanistic models across 9 de-identified trachoma endemic districts, representing 4 unique trachoma endemic countries. We forecast TF prevalence between 1-6 years ahead in time and compare the 7 different models to the observed 2011 data using a log-likelihood score. An SIS model, including a district-specific random effect for the district-specific transmission coefficient, had the highest log-likelihood score across all 9 districts and was therefore the best performing model...
March 2017: Epidemics
https://www.readbyqxmd.com/read/28279455/modelling-the-elimination-of-river-blindness-using-long-term-epidemiological-and-programmatic-data-from-mali-and-senegal
#19
Martin Walker, Wilma A Stolk, Matthew A Dixon, Christian Bottomley, Lamine Diawara, Mamadou O Traoré, Sake J de Vlas, María-Gloria Basáñez
The onchocerciasis transmission models EPIONCHO and ONCHOSIM have been independently developed and used to explore the feasibility of eliminating onchocerciasis from Africa with mass (annual or biannual) distribution of ivermectin within the timeframes proposed by the World Health Organization (WHO) and endorsed by the 2012 London Declaration on Neglected Tropical Diseases (i.e. by 2020/2025). Based on the findings of our previous model comparison, we implemented technical refinements and tested the projections of EPIONCHO and ONCHOSIM against long-term epidemiological data from two West African transmission foci in Mali and Senegal where the observed prevalence of infection was brought to zero circa 2007-2009 after 15-17 years of mass ivermectin treatment...
March 2017: Epidemics
https://www.readbyqxmd.com/read/28279454/comparison-and-validation-of-two-mathematical-models-for-the-impact-of-mass-drug-administration-on-ascaris-lumbricoides-and-hookworm-infection
#20
Luc E Coffeng, James E Truscott, Sam H Farrell, Hugo C Turner, Rajiv Sarkar, Gagandeep Kang, Sake J de Vlas, Roy M Anderson
The predictions of two mathematical models of the transmission dynamics of Ascaris lumbricoides and hookworm infection and the impact of mass drug administration (MDA) are compared, using data from India. One model has an age structured partial differential equation (PDE) deterministic framework for the distribution of parasite numbers per host and sexual mating. The second model is an individual-based stochastic model. Baseline data acquired prior to treatment are used to estimate key transmission parameters, and forward projections are made, given the known MDA population coverage...
March 2017: Epidemics
journal
journal
42159
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"