920 research outputs found
Cholera—Modern Pandemic Disease of Ancient Lineage
Environmental triggers may lead to increases in Vibrio cholerae in environmental reservoirs, with spillover into human populations
Ranking the Risks: The 10 Pathogen-Food Combinations With the Greatest Burden on Public Health
Examines food-borne pathogens with the highest disease burdens and the top ten foods most commonly contaminated by them, such as salmonella in poultry, toxoplasma in pork, and listeria in deli meats. Makes policy recommendations for improving prevention
Hyperinfectivity: A Critical Element in the Ability of V. cholerae to Cause Epidemics?
BACKGROUND: Cholera is an ancient disease that continues to cause epidemic and pandemic disease despite ongoing efforts to limit its spread. Mathematical models provide one means of assessing the utility of various proposed interventions. However, cholera models that have been developed to date have had limitations, suggesting that there are basic elements of cholera transmission that we still do not understand. METHODS AND FINDINGS: Recent laboratory findings suggest that passage of Vibrio cholerae O1 Inaba El Tor through the gastrointestinal tract results in a short-lived, hyperinfectious state of the organism that decays in a matter of hours into a state of lower infectiousness. Incorporation of this hyperinfectious state into our disease model provides a much better fit with the observed epidemic pattern of cholera. These findings help to substantiate the clinical relevance of laboratory observations regarding the hyperinfectious state, and underscore the critical importance of human-to-human versus environment-to-human transmission in the generation of epidemic and pandemic disease. CONCLUSIONS: To have maximal impact on limiting epidemic spread of cholera, interventions should be targeted toward minimizing risk of transmission of the short-lived, hyperinfectious form of toxigenic Vibrio cholerae. The possibility of comparable hyperinfectious states in other major epidemic diseases also needs to be evaluated and, as appropriate, incorporated into models of disease prevention
Joint Application of the Target Trial Causal Framework and Machine Learning Modeling to Optimize Antibiotic Therapy: Use Case on Acute Bacterial Skin and Skin Structure Infections due to Methicillin-resistant Staphylococcus aureus
Bacterial infections are responsible for high mortality worldwide.
Antimicrobial resistance underlying the infection, and multifaceted patient's
clinical status can hamper the correct choice of antibiotic treatment.
Randomized clinical trials provide average treatment effect estimates but are
not ideal for risk stratification and optimization of therapeutic choice, i.e.,
individualized treatment effects (ITE). Here, we leverage large-scale
electronic health record data, collected from Southern US academic clinics, to
emulate a clinical trial, i.e., 'target trial', and develop a machine learning
model of mortality prediction and ITE estimation for patients diagnosed with
acute bacterial skin and skin structure infection (ABSSSI) due to
methicillin-resistant Staphylococcus aureus (MRSA). ABSSSI-MRSA is a
challenging condition with reduced treatment options - vancomycin is the
preferred choice, but it has non-negligible side effects. First, we use
propensity score matching to emulate the trial and create a treatment
randomized (vancomycin vs. other antibiotics) dataset. Next, we use this data
to train various machine learning methods (including boosted/LASSO logistic
regression, support vector machines, and random forest) and choose the best
model in terms of area under the receiver characteristic (AUC) through
bootstrap validation. Lastly, we use the models to calculate ITE and identify
possible averted deaths by therapy change. The out-of-bag tests indicate that
SVM and RF are the most accurate, with AUC of 81% and 78%, respectively, but
BLR/LASSO is not far behind (76%). By calculating the counterfactuals using the
BLR/LASSO, vancomycin increases the risk of death, but it shows a large
variation (odds ratio 1.2, 95% range 0.4-3.8) and the contribution to outcome
probability is modest. Instead, the RF exhibits stronger changes in ITE,
suggesting more complex treatment heterogeneity.Comment: This is the Proceedings of the KDD workshop on Applied Data Science
for Healthcare (DSHealth 2022), which was held on Washington D.C, August 14
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Researching Zika in pregnancy:lessons for global preparedness
Our understanding of congenital infections is based on prospective studies of women infected during pregnancy. The EU has funded three consortia to study Zika virus, each including a prospective study of pregnant women. Another multi-centre study has been funded by the US National Institutes of Health. This Personal View describes the study designs required to research Zika virus, and questions whether funding academics in the EU and USA to work with collaborators in outbreak areas is an effective strategy. 3 years after the 2015\u201316 Zika virus outbreaks, these collaborations have taught us little about vertical transmission of the virus. In the time taken to approve funding, agree contracts, secure ethics approval, and equip laboratories, Zika virus had largely disappeared. By contrast, prospective studies based on local surveillance and standard-of-care protocols have already provided valuable data. Threats to fetal and child health pose new challenges for global preparedness requiring support for the design and implementation of locally appropriate protocols. These protocols can answer the key questions earlier than externally designed studies and at lower cost. Local protocols can also provide a framework for recruitment of unexposed controls that are required to study less specific outcomes. Other priorities include accelerated development of non-invasive tests, and longer-term storage of neonatal and antenatal samples to facilitate retrospective reconstruction of cohort studies
Attributing Illness to Food
Identification and prioritization of effective food safety interventions require an understanding of the relationship between food and pathogen from farm to consumption. Critical to this cause is food attribution, the capacity to attribute cases of foodborne disease to the food vehicle or other source responsible for illness. A wide variety of food attribution approaches and data are used around the world, including the analysis of outbreak data, case-control studies, microbial subtyping and source tracking methods, and expert judgment, among others. The Food Safety Research Consortium sponsored the Food Attribution Data Workshop in October 2003 to discuss the virtues and limitations of these approaches and to identify future options for collecting food attribution data in the United States. We summarize workshop discussions and identify challenges that affect progress in this critical component of a risk-based approach to improving food safety
Characterization of pPCP1 Plasmids in Yersinia pestis Strains Isolated from the Former Soviet Union
Complete sequences of 9.5-kb pPCP1 plasmids in three Yersinia pestis strains from the former Soviet Union (FSU) were determined and compared with those of pPCP1 plasmids in three well-characterized, non-FSU Y. pestis strains (KIM, CO92, and 91001). Two of the FSU plasmids were from strains C2614 and C2944, isolated from plague foci in Russia, and one plasmid was from strain C790 from Kyrgyzstan. Sequence analyses identified four sequence types among the six plasmids. The pPCP1 plasmids in the FSU strains were most genetically related to the pPCP1 plasmid in the KIM strain and least related to the pPCP1 plasmid in Y. pestis 91001. The FSU strains generally had larger pPCP1 plasmid copy numbers compared to strain CO92. Expression of the plasmid's pla gene was significantly (P ≤ .05) higher in strain C2944 than in strain CO92. Given pla's role in Y. pestis virulence, this difference may have important implications for the strain's virulence
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