Evolution of a transdisciplinary "One Medicine-One Health" approach to global health education at the University of California, Davis.

In today's world health events in one nation or geographic area often have repercussions for the health and well-being of populations beyond that region; sometimes even globally. In recent years many factors, most notably concern about emerging infectious diseases, have contributed to an increasing appreciation of the interdependency of human, animal and ecosystem health worldwide. Integrated global approaches to improve the health of humans, animals and their shared environments are proving to be in the best interest of many countries. A special symposium and award were established in memoriam to the internationally renowned epidemiologist, Dr. Calvin W. Schwabe, who (while at the University of California, Davis) was a significant advocate of the "One Medicine" approach to public health, calling upon all health professionals, including veterinarians, to work collaboratively and comparatively to improve human health. This paper discusses the evolution of the "One Medicine" concept into a global "One Health" approach to research, training capacity and service infrastructure, focused not only on disease, but also on health at the individual, population, and ecosystem levels. Projects involving UCD faculty which attempt to integrate a One Health approach include the Health for Animals and Livelihood Improvement (HALI) Project in Tanzania, Envirovet Summer Institute, Avian Flu School and Newcastle Immunization Program in Africa, a web-based virtual global health training program, and the Calvin Schwabe One Health Project

Aquatic polymers can drive pathogen transmission in coastal ecosystems.

Gelatinous polymers including extracellular polymeric substances (EPSs) are fundamental to biophysical processes in aquatic habitats, including mediating aggregation processes and functioning as the matrix of biofilms. Yet insight into the impact of these sticky molecules on the environmental transmission of pathogens in the ocean is limited. We used the zoonotic parasite Toxoplasma gondii as a model to evaluate polymer-mediated mechanisms that promote transmission of terrestrially derived pathogens to marine fauna and humans. We show that transparent exopolymer particles, a particulate form of EPS, enhance T. gondii association with marine aggregates, material consumed by organisms otherwise unable to access micrometre-sized particles. Adhesion to EPS biofilms on macroalgae also captures T. gondii from the water, enabling uptake of pathogens by invertebrates that feed on kelp surfaces. We demonstrate the acquisition, concentration and retention of T. gondii by kelp-grazing snails, which can transmit T. gondii to threatened California sea otters. Results highlight novel mechanisms whereby aquatic polymers facilitate incorporation of pathogens into food webs via association with particle aggregates and biofilms. Identifying the critical role of invisible polymers in transmission of pathogens in the ocean represents a fundamental advance in understanding and mitigating the health impacts of coastal habitat pollution with contaminated runoff

Native rodent species are unlikely sources of infection for Leishmania (Viannia) braziliensis along the Transoceanic Highway in Madre de Dios, Peru.

An estimated 2.3 million disability-adjusted life years are lost globally from leishmaniasis. In Peru's Amazon region, the department of Madre de Dios (MDD) rises above the rest of the country in terms of the annual incidence rates of human leishmaniasis. Leishmania (Viannia) braziliensis is the species most frequently responsible for the form of disease that results in tissue destruction of the nose and mouth. However, essentially nothing is known regarding the reservoirs of this vector-borne, zoonotic parasite in MDD. Wild rodents have been suspected, or proven, to be reservoirs of several Leishmania spp. in various ecosystems and countries. Additionally, people who live or work in forested terrain, especially those who are not regionally local and whose immune systems are thus naïve to the parasite, are at most risk for contracting L. (V.) braziliensis. Hence, the objective of this study was to collect tissues from wild rodents captured at several study sites along the Amazonian segment of the newly constructed Transoceanic Highway and to use molecular laboratory techniques to analyze samples for the presence of Leishmania parasites. Liver tissues were tested via polymerase chain reaction from a total of 217 rodents; bone marrow and skin biopsies (ear and tail) were also tested from a subset of these same animals. The most numerous rodent species captured and tested were Oligoryzomys microtis (40.7%), Hylaeamys perenensis (15.7%), and Proechimys spp. (12%). All samples were negative for Leishmania, implying that although incidental infections may occur, these abundant rodent species are unlikely to serve as primary reservoirs of L. (V.) braziliensis along the Transoceanic Highway in MDD. Therefore, although these rodent species may persist and even thrive in moderately altered landscapes, we did not find any evidence to suggest they pose a risk for L. (V.) braziliensis transmission to human inhabitants in this highly prevalent region

Spatial epidemiological patterns suggest mechanisms of land-sea transmission for Sarcocystis neurona in a coastal marine mammal.

Sarcocystis neurona was recognised as an important cause of mortality in southern sea otters (Enhydra lutris nereis) after an outbreak in April 2004 and has since been detected in many marine mammal species in the Northeast Pacific Ocean. Risk of S. neurona exposure in sea otters is associated with consumption of clams and soft-sediment prey and is temporally associated with runoff events. We examined the spatial distribution of S. neurona exposure risk based on serum antibody testing and assessed risk factors for exposure in animals from California, Washington, British Columbia and Alaska. Significant spatial clustering of seropositive animals was observed in California and Washington, compared with British Columbia and Alaska. Adult males were at greatest risk for exposure to S. neurona, and there were strong associations with terrestrial features (wetlands, cropland, high human housing-unit density). In California, habitats containing soft sediment exhibited greater risk than hard substrate or kelp beds. Consuming a diet rich in clams was also associated with increased exposure risk. These findings suggest a transmission pathway analogous to that described for Toxoplasma gondii, with infectious stages traveling in freshwater runoff and being concentrated in particular locations by marine habitat features, ocean physical processes, and invertebrate bioconcentration

Normalizing Deviants: Notes on the De-Stigma Trend

This article explores destigmatization discourses in the United States in the early 21st century, as social and political strategies and as narrative social movements unto themselves. We argue that the first decades of the new century see a trend of marginalized actors across many categories, including queer marriage, drugs, (discreditable) mental illness and (discredited) other areas of identity and disability, make narrative attempts to neutralize their “deviant” identities. We argue that de-stigmatization has occurred through the successful use of medicalization and assimilation framing of de-stigma discourses. Assimilationist frames increase “liberal” emphasis on actionable outcomes of de-stigma, like cultural access (i.e. inclusion, visibility, representation), and legal justice for marginalized people. Some assimilationist discourse endeavors to situate stigmatized identities inside of conformist frames, while (fewer and less visible) others resist dominant frames of acceptability. Contested assimilation and radical leftist de-stigmatization, as well as re-stigma discourses are also discussed

A Theorem on Matroid Homomorphism

This note generalizes a result contained in a previous paper [ J. Sanders, Circuit preserving edge maps II, J. Combin. Theory Ser. B 42 (1987), 146-155].Comment: 5 pages, 0 figure