202 results found
Cori A, Donnelly CA, dorigatti, et al., Key data for outbreak evaluation: building on the Ebola experience, Philosophical Transactions of the Royal Society B: Biological Sciences, ISSN: 1471-2970
Following the detection of an infectious disease outbreak, rapid epidemiological assessmentis critical to guidean effectivepublic health response. To understand the transmission dynamics and potential impact of an outbreak, several types of data are necessary. Here we build on experience gained inthe West AfricanEbolaepidemic and prior emerging infectious disease outbreaksto set out a checklist of data needed to: 1) quantify severity and transmissibility;2) characterise heterogeneities in transmission and their determinants;and 3) assess the effectiveness of different interventions.We differentiate data needs into individual-leveldata (e.g. a detailed list of reported cases), exposure data(e.g.identifying where / howcases may have been infected) and populationlevel data (e.g.size/demographicsof the population(s)affected andwhen/where interventions were implemented). A remarkable amount of individual-level and exposuredata was collected during the West African Ebola epidemic, which allowed the assessment of (1) and (2). However,gaps in population-level data (particularly around which interventions were applied whenand where)posed challenges to the assessment of (3).Herewehighlight recurrent data issues, give practical suggestions for addressingthese issues and discuss priorities for improvements in data collection in future outbreaks.
Garske T, Cori A, Ariyarajah A, et al., Heterogeneities in the case fatality ratio in the West African Ebola outbreak 2013 – 2016, Philosophical Transactions of the Royal Society B: Biological Sciences, ISSN: 1471-2970
The 2013 –2016 Ebola outbreak in West Africa is the largest on record with 28,616confirmed, probable and suspected casesand 11,310 deaths officially recorded by 10 June 2016, the true burden likely considerablyhigher. The case fatality ratio (CFR, proportion of cases that are fatal) is a key indicator of disease severity useful for gauging the appropriate public health response and for evaluating treatment benefits,if estimated accurately.We analysed individual-level clinical outcome data fromGuinea, Liberia and Sierra Leoneofficially reported tothe World Health Organization. The overall mean CFR was 62.9% (95% CI: 61.9% to 64.0%)among confirmed cases with recorded clinical outcomes. Age was the most important modifier of survival probabilities, but country, stage of the epidemic and whether patients were hospitalisedalso played roles. We developed a statistical analysis to detect outliers in CFR between districts of residence and treatment centres, adjusting for known factors influencing survival and identified eight districtsand three treatment centres with a CFR significantly different from the average. From the current dataset we cannot determine whether the observed variation in CFR seen by district or treatment centre reflects real differences in survival, related to the quality of care or other factors,or was caused by differences in reporting practices or case ascertainment.
Agua-Agum J, Allegranzi B, Ariyarajah A, et al., 2016, After Ebola in West Africa - Unpredictable Risks, Preventable Epidemics, NEW ENGLAND JOURNAL OF MEDICINE, Vol: 375, Pages: 587-596, ISSN: 0028-4793
Agua-Agum J, Ariyarajah A, Aylward B, et al., 2016, Exposure Patterns Driving Ebola Transmission in West Africa: A Retrospective Observational Study, PLOS MEDICINE, Vol: 13, ISSN: 1549-1676
Agua-Agum J, Ariyarajah A, Blake IM, et al., 2016, Ebola Virus Disease among Male and Female Persons in West Africa, NEW ENGLAND JOURNAL OF MEDICINE, Vol: 374, Pages: 96-98, ISSN: 0028-4793
Cauchemez S, Nouvellet P, Cori A, et al., 2016, Unraveling the drivers of MERS-CoV transmission, PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, Vol: 113, Pages: 9081-9086, ISSN: 0027-8424
Clapham HE, Than HQ, Duong THK, et al., 2016, Modelling Virus and Antibody Dynamics during Dengue Virus Infection Suggests a Role for Antibody in Virus Clearance, PLOS COMPUTATIONAL BIOLOGY, Vol: 12, ISSN: 1553-734X
Ferguson NM, Rodriguez-Barraquer I, Dorigatti I, et al., 2016, Benefits and risks of the Sanofi-Pasteur dengue vaccine: Modeling optimal deployment, SCIENCE, Vol: 353, Pages: 1033-1036, ISSN: 0036-8075
Flasche S, Jit M, Rodriguez-Barraquer I, et al., 2016, The Long-Term Safety, Public Health Impact, and Cost-Effectiveness of Routine Vaccination with a Recombinant, Live-Attenuated Dengue Vaccine (Dengvaxia): A Model Comparison Study, PLOS MEDICINE, Vol: 13, ISSN: 1549-1676
Fumanellil L, Ajelli M, Merler S, et al., 2016, Model-Based Comprehensive Analysis of School Closure Policies for Mitigating Influenza Epidemics and Pandemics, PLOS COMPUTATIONAL BIOLOGY, Vol: 12, ISSN: 1553-734X
Imai N, Dorigatti I, Cauchemez S, et al., 2016, Estimating Dengue Transmission Intensity from Case-Notification Data from Multiple Countries, PLOS NEGLECTED TROPICAL DISEASES, Vol: 10, ISSN: 1935-2735
Jean K, Donnelly CA, Ferguson NM, et al., 2016, A Meta-Analysis of Serological Response Associated with Yellow Fever Vaccination., Am J Trop Med Hyg, Vol: 95, Pages: 1435-1439
Despite previous evidence of high level of efficacy, no synthetic metric of yellow fever (YF) vaccine efficacy is currently available. Based on the studies identified in a recent systematic review, we conducted a random-effects meta-analysis of the serological response associated with YF vaccination. Eleven studies conducted between 1965 and 2011 representing 4,868 individual observations were included in the meta-analysis. The pooled estimate of serological response was 97.5% (95% confidence interval [CI] = 82.9-99.7%). There was evidence of between-study heterogeneity (I(2) = 89.1%), but this heterogeneity did not appear to be related to study size, study design, or seroconversion measurement or definition. Pooled estimates were significantly higher (P < 0.0001) among studies conducted in nonendemic settings (98.9%, 95% CI = 98.2-99.4%) than among those conducted in endemic settings (94.2%, 95% CI = 83.8-98.1%). These results provide background information against which to evaluate the efficacy of fractional doses of YF vaccine that may be used in outbreak situations.
Karkey A, Jombart T, Walker AW, et al., 2016, The Ecological Dynamics of Fecal Contamination and Salmonella Typhi and Salmonella Paratyphi A in Municipal Kathmandu Drinking Water, PLOS NEGLECTED TROPICAL DISEASES, Vol: 10, ISSN: 1935-2735
Lessler J, Salje H, Van Kerkhove MD, et al., 2016, Estimating the Severity and Subclinical Burden of Middle East Respiratory Syndrome Coronavirus Infection in the Kingdom of Saudi Arabia, AMERICAN JOURNAL OF EPIDEMIOLOGY, Vol: 183, Pages: 657-663, ISSN: 0002-9262
Majeed A, Hansell A, Saxena S, et al., 2016, How would a decision to leave the European Union affect medical research and health in the United Kingdom?, JOURNAL OF THE ROYAL SOCIETY OF MEDICINE, Vol: 109, Pages: 216-218, ISSN: 0141-0768
Marshall JM, Toure M, Ouedraogo AL, et al., 2016, Key traveller groups of relevance to spatial malaria transmission: a survey of movement patterns in four sub-Saharan African countries, MALARIA JOURNAL, Vol: 15, ISSN: 1475-2875
Metcalf CJE, Farrar J, Cutts FT, et al., 2016, Use of serological surveys to generate key insights into the changing global landscape of infectious disease, LANCET, Vol: 388, Pages: 728-730, ISSN: 0140-6736
Pinsent A, Fraser C, Ferguson NM, et al., 2016, A systematic review of reported reassortant viral lineages of influenza A, BMC INFECTIOUS DISEASES, Vol: 16, ISSN: 1471-2334
Pothin E, Ferguson NM, Drakeley CJ, et al., 2016, Estimating malaria transmission intensity from Plasmodium falciparum serological data using antibody density models, MALARIA JOURNAL, Vol: 15, ISSN: 1475-2875
Walker PGT, Griffin JT, Ferguson NM, et al., 2016, Estimating the most efficient allocation of interventions to achieve reductions in Plasmodium falciparum malaria burden and transmission in Africa: a modelling study, LANCET GLOBAL HEALTH, Vol: 4, Pages: E474-E484, ISSN: 2214-109X
Dorigatti I, Aguas R, Donnelly CA, et al., 2015, Modelling the immunological response to a tetravalent dengue vaccine from multiple phase-2 trials in Latin America and South East Asia., Vaccine, Vol: 33, Pages: 3746-3751, ISSN: 1873-2518
BACKGROUND: The most advanced dengue vaccine candidate is a live-attenuated recombinant vaccine containing the four dengue viruses on the yellow fever vaccine backbone (CYD-TDV) developed by Sanofi Pasteur. Several analyses have been published on the safety and immunogenicity of the CYD-TDV vaccine from single trials but none modelled the heterogeneity observed in the antibody responses elicited by the vaccine. METHODS: We analyse the immunogenicity data collected in five phase-2 trials of the CYD-TDV vaccine. We provide a descriptive analysis of the aggregated datasets and fit the observed post-vaccination PRNT50 titres against the four dengue (DENV) serotypes using multivariate regression models. RESULTS: We find that the responses to CYD-TDV are principally predicted by the baseline immunological status against DENV, but the trial is also a significant predictor. We find that the CYD-TDV vaccine generates similar titres against all serotypes following the third dose, though DENV4 is immunodominant after the first dose. CONCLUSIONS: This study contributes to a better understanding of the immunological responses elicited by CYD-TDV. The recent availability of phase-3 data is a unique opportunity to further investigate the immunogenicity and efficacy of the CYD-TDV vaccine, especially in subjects with different levels of pre-existing immunity against DENV. Modelling multiple immunological outcomes with a single multivariate model offers advantages over traditional approaches, capturing correlations between response variables, and the statistical method adopted in this study can be applied to a variety of infections with interacting strains.
Ferguson NM, Duong THK, Clapham H, et al., 2015, Modeling the impact on virus transmission of Wolbachia-mediated blocking of dengue virus infection of Aedes aegypti, SCIENCE TRANSLATIONAL MEDICINE, Vol: 7, ISSN: 1946-6234
Gambhir M, Clark TA, Cauchemez S, et al., 2015, A Change in Vaccine Efficacy and Duration of Protection Explains Recent Rises in Pertussis Incidence in the United States, PLOS COMPUTATIONAL BIOLOGY, Vol: 11, ISSN: 1553-734X
Imai N, Dorigatti I, Cauchemez S, et al., 2015, Estimating Dengue Transmission Intensity from Sero-Prevalence Surveys in Multiple Countries, PLOS NEGLECTED TROPICAL DISEASES, Vol: 9, ISSN: 1935-2735
Lambrechts L, Ferguson NM, Harris E, et al., 2015, Assessing the epidemiological effect of wolbachia for dengue control, LANCET INFECTIOUS DISEASES, Vol: 15, Pages: 862-866, ISSN: 1473-3099
Lipsitch M, Donnelly CA, Fraser C, et al., 2015, Potential Biases in Estimating Absolute and Relative Case-Fatality Risks during Outbreaks, PLOS NEGLECTED TROPICAL DISEASES, Vol: 9, ISSN: 1935-2735
Nouvellet P, Garske T, Mills HL, et al., 2015, The role of rapid diagnostics in managing Ebola epidemics, NATURE, Vol: 528, Pages: S109-S116, ISSN: 0028-0836
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.