Salamanders increase their feeding activity when infected with the pathogenic chytrid fungus Batrachochytrium dendrobatidis.

Immune function is a costly line of defense against parasitism. When infected with a parasite, hosts frequently lose mass due to these costs. However, some infected hosts (e.g. highly resistant individuals) can clear infections with seemingly little fitness losses, but few studies have tested how resistant hosts mitigate these costly immune defenses. We explored this topic using eastern red-backed salamanders Plethodon cinereus and the fungal pathogen Batrachochytrium dendrobatidis (Bd). Bd is generally lethal for amphibians, and stereotypical symptoms of infection include loss in mass and deficits in feeding. However, individuals of P. cinereus can clear their Bd infections with seemingly few fitness costs. We conducted an experiment in which we repeatedly observed the feeding activity of Bd-infected and non-infected salamanders. We found that Bd-infected salamanders generally increased their feeding activity compared to non-infected salamanders. The fact that we did not observe any differences in mass change between the treatments suggests that increased feeding might help Bd-infected salamanders minimize the costs of an effective immune response.

Assessment of Clinical Reasoning in Undergraduate Medical Education: A Pragmatic Approach to Programmatic Assessment.

PURPOSE: Clinical reasoning, a complex construct integral to the practice of medicine, has been challenging to define, teach, and assess. Programmatic assessment purports to overcome validity limitations of judgments made from individual assessments through proportionality and triangulation processes. This study explored a pragmatic approach to the programmatic assessment of clinical reasoning. METHOD: The study analyzed data from 2 student cohorts from the University of Utah School of Medicine (UUSOM) (n = 113 in cohort 1 and 119 in cohort 2) and 1 cohort from the University of Colorado School of Medicine (CUSOM) using assessment data that spanned from 2017 to 2021 (n = 199). The study methods included the following: (1) asking faculty judges to categorize student clinical reasoning skills, (2) selecting institution-specific assessment data conceptually aligned with clinical reasoning, (3) calculating correlations between assessment data and faculty judgments, and (4) developing regression models between assessment data and faculty judgments. RESULTS: Faculty judgments of student clinical reasoning skills were converted to a continuous variable of clinical reasoning struggles, with mean (SD) ratings of 2.93 (0.27) for the 232 UUSOM students and 2.96 (0.17) for the 199 CUSOM students. A total of 67 and 32 discrete assessment variables were included from the UUSOM and CUSOM, respectively. Pearson r correlations were moderate to strong between many individual and composite assessment variables and faculty judgments. Regression models demonstrated an overall adjusted R2 (standard error of the estimate) of 0.50 (0.19) for UUSOM cohort 1, 0.28 (0.15) for UUSOM cohort 2, and 0.30 (0.14) for CUSOM. CONCLUSIONS: This study represents an early pragmatic exploration of regression analysis as a potential tool for operationalizing the proportionality and triangulation principles of programmatic assessment. The study found that programmatic assessment may be a useful framework for longitudinal assessment of complicated constructs, such as clinical reasoning.

Travel counsellors and travel health advice.

BACKGROUND: Travel Counsellors may be a source of health advice to travellers and might influence travellers' decisions to seek consultation from health professionals. We examined the travel health advice that Alberta travel counsellors currently provide their clients and assessed their health knowledge and practices. METHODS: Cross-sectional postal survey of travel counsellors who book international trips identified from a random sample of Alberta travel agencies in 2000. RESULTS: The response rate was 54.4%. Over 80% of respondents routinely provide clients with general health advice, and approximately 70% advise on malaria risk and vaccines required for travel. The risk of malaria was correctly identified by 72% of the respondents who frequently book clients to malarious destinations. Most respondents (79%) thought they should be involved in promoting the health of international travellers. Their preference was to provide health advice to their clients (90%) rather than refer them to a health professional (67%). CONCLUSIONS: A large proportion of Alberta travel counsellors provided travel-related health advice to clients. Their preferred role of counselling rather than referring conflicts with the recommendations of the International Society of Travel Medicine.

Innate immunity to malaria caused by Plasmodium falciparum.

Malaria, a widespread disease caused by protozoa of the genus Plasmodium, contributes to the death of more than 2 million people each year. Resistance to antimalarial drugs is increasing, and an effective vaccine has not yet been designed. In the search for alternative means to control malaria infections, especially those caused by the most lethal species of malaria parasite, Plasmodium falciparum, our attention has turned to elucidating the relationships of the parasite and human host at the molecular level. In this review, we describe possible mechanisms by which naturally occurring genetic mutations might confer resistance to P. falciparum and how our innate immune response mediated by the phagocytic action of monocytes and macrophages acts as a first-line defence in clearing malaria infections. The potential effectiveness of novel therapies to enhance innate phagocytic clearance of malaria parasites, particularly in nonimmune people who are at greatest risk of adverse outcomes, is also discussed.