Diversity, prevalence, and intensity of gastrointestinal helminth infections in migratory, resident, and sedentary plains zebras (Equus quagga) in Masai Mara National Reserve and Lake Nakuru National Park, Kenya.

The diversity, prevalence and intensity of parasitic infections are influenced by factors such as movement patterns and land area available to the host. Zebras are known to harbour various genera of gastrointestinal helminths and facilitate parasite movement across large geographic areas through migration. Despite the harmful effects of helminths and their consequences on host population dynamics, little is known regarding helminth infection patterns in migratory, resident, and sedentary zebras. This study compared the diversity, prevalence, and intensity of helminth infections in zebras with different host movement patterns and space availability. Faecal samples were collected from migratory, resident, and sedentary groups of zebras between 2014 and 2015 and screened for helminth infection. They were infected by diverse groups of helminths including nematodes, trematodes and cestodes with the most prevalent being strongyle type nematodes. No significant difference in the diversity and prevalence was observed between the "three groups". Larvae were also recovered and identified species, cyathostomes, Strongylus edentatus, S.vulgaris, S. equinus, and Trichostronglus in order of abundance. The intensity of infection with the strongyle type nematodes, was highest in the migratory, then sedentary and lowest in resident zebras. It is plausible that the migratory zebras have higher energy demands and poor nutrition, resulting in reduced immune function hence high nematode burdens. Similarly, the sedentary population had high nematode burdens possibly due to high pasture contamination and depressed immunity due to the artificially restricted movement. The latter observation is particularly important in the design and size of sanctuaries in relation to parasitism.

Rural prioritization may increase the impact of COVID-19 vaccines in a representative COVAX AMC country setting due to ongoing internal migration: A modeling study.

How COVID-19 vaccine is distributed within low- and middle-income countries has received little attention outside of equity or logistical concerns but may ultimately affect campaign impact in terms of infections, severe cases, or deaths averted. In this study we examined whether subnational (urban-rural) prioritization may affect the cumulative two-year impact on disease transmission and burden of a vaccination campaign using an agent-based model of COVID-19 in a representative COVID-19 Vaccines Global Access (COVAX) Advanced Market Commitment (AMC) setting. We simulated a range of vaccination strategies that differed by urban-rural prioritization, age group prioritization, timing of introduction, and final coverage level. Urban prioritization averted more infections in only a narrow set of scenarios, when internal migration rates were low and vaccination was started by day 30 of an outbreak. Rural prioritization was the optimal strategy for all other scenarios, e.g., with higher internal migration rates or later start dates, due to the presence of a large immunological naive rural population. Among other factors, timing of the vaccination campaign was important to determining maximum impact, and delays as short as 30 days prevented larger campaigns from having the same impact as smaller campaigns that began earlier. The optimal age group for prioritization depended on choice of metric, as prioritizing older adults consistently averted more deaths across all of the scenarios. While guidelines exist for these latter factors, urban-rural allocation is an orthogonal factor that we predict to affect impact and warrants consideration as countries plan the scale-up of their vaccination campaigns.

Effects of CRH, ACTH and the corticostatin HP-4 on the spontaneous NK cell activity and susceptibility to endogenous modifiers.

Natural killer (NK) cells are mononuclear leukocytes which are thought to play an important role in immunosurveillance; in the elderly a progressive reduction occurs both of their spontaneous activity and of their responsiveness to positive modulators such as immune interferon (IFN-y) and interleukin-2 (IL-2). NK cells represent also a reliable model to study immunomodulatory properties of the hypothalamic-pituitary-adrenal (HPA) system, since cortisol (F) is a well defined inhibitor of their activity whereas proopiomelanocortin (POMC)-derived peptides may counteract this effect. Corticostatins (CS)-defensins are a family of peptides recently purified from cells capable of phagocytic activity; they are able to inhibit the steroidogenic activity of ACTH and to enhance internalization and/or killing of intracellular pathogens. We have investigated the effects in vitro of corticotropin releasing hormone (CRH), ACTH and CS HP-4 on human NK cell activity. Peripheral blood mononuclear (PBM) cells from healthy donors were incubated with CRH (10(-14)-10(-11) M). ACTH (10(-12)-10(-8) M) and HP-4 (10(-10)-10(-8) M) in the presence or absence of F (10(-6) M) or IFN-y (325 IU//ml) or IL-2 (25 IU/ml). NK cell activity was measured in a 4-h cytotoxic assay using K562 cells as a target. CRH was able to significantly reduce the spontaneous and IL-2-induced NK activity and to significantly potentiate the F-dependent inhibition. ACTH was per se ineffective on the spontaneous NK activity, but was able to augment the enhancing effects of IFN-y and IL-2, and to reduce the degree of inhibition obtainable with the glucocorticoid. HP-4 was able to enhance the F-dependent inhibition of PBM preparations. Our results are consistent with an immunomodulatory role for CRH, ACTH and CS, specially in conditions of high concentrations of glucocorticoids. Since in elderly has been demonstrated a condition of hypercortisolism, we suggest that complex steroid-peptides interactions are involved in the net effect of HPA axis on immune functions in senescence, and that such interactions involve paracrine/autocrine CS.

Hospital health professionals' education about organ and tissue donation: a Turin hospital experience.

The culture of organ and tissue donation is not particularly well established among the general population, who often receive incorrect, incomplete information. Unfortunately, even among health workers not directly involved in the field of transplantation (laypersons), there is a poor level of knowledge concerning the underlying principles, mechanisms, and results. To increase lay health workers' knowledge and awareness of the importance of donation and transplantation, we organized an educational session for (nurses, doctors, healthcare workers, technicians, and other professionals) at a hospital coordinating service in Turin. The project was divided into 3 phases: first (February 2010), we performed an initial survey using an instrument containing 18 questions. We sought to assess the level of awareness of hospital personnel. Among 880 distributed questionnaires, 346 were compiled and returned to the authors (39.31%). During the second phase, covering the following 24 months, we held 15 educational courses on the subject of transplantation for 483 participants. In the third and last phase (February 2012), we performed a second survey, distributing, 785 questionnaires identical to the previous one, among which 404 were compiled and returned (51.46%).