Oral Immunization of Wildlife Against Rabies: Concept and First Field Experiments

The possibility of immunizing carnivores against rabies with live attenuated vaccine administered by the oral route was raised by North American scientists in the 1960s. Subsequently, several American and European teams tested different vaccine strains in the laboratory for efficacy and safety and studied vaccine stabilization, vaccine delivery systems, baIt acceptance by wl1d ammals, and bait distribution schemes. The first field trial of a cloned SAD (Street Alabama Dufferin) strain in baits designed to immunize foxes orally ~as conducted in an Alpine valley in Switzerland in 1978. A population containing ∼60% immune foxes at the valley entrance stopped the spread of the disease into untreated upper parts of the valley. T~e strategic use of oral vaccination of foxes in additional regions of SWItzerland resulted m freedom from the zoonosis in four-fifths of the countr

Oral Immunization of Wildlife Against Rabies: Concept and First Field Experiments

The possibility of immunizing carnivores against rabies with live attenuated vaccine administered by the oral route was raised by North American scientists in the 1960s. Subsequently, several American and European teams tested different vaccine strains in the laboratory for efficacy and safety and studied vaccine stabilization, vaccine delivery systems, baIt acceptance by wl1d ammals, and bait distribution schemes. The first field trial of a cloned SAD (Street Alabama Dufferin) strain in baits designed to immunize foxes orally ~as conducted in an Alpine valley in Switzerland in 1978. A population containing ∼60% immune foxes at the valley entrance stopped the spread of the disease into untreated upper parts of the valley. T~e strategic use of oral vaccination of foxes in additional regions of SWItzerland resulted m freedom from the zoonosis in four-fifths of the country

Dog Ecology and Dog Rabies Control

Dog populations, like other populations, depend on the availability of resources (food, water, and shelter). Humans either make available or deliberately withhold resources for varying proportions of dog populations. Dog-keeping practices and the duties of responsible ownership vary with the cultural setting. Dog populations often attain densities that allow the species to be a main host of rabies. The epidemiology of dog rabies is not well understood, despite the easy access to dog populations. Today dog rabies is predomina~t in developing countries. In addition to the high rate of exposure of humans to dogs, tradItional medical beliefs and practices are the most important cultural factors that lead to high numbers of cases of human rabies. Dog rabies control programs have been succe~sful in the past, but most are failing today. Program development should follow managenal principles and take into consideration the biology of dog populations as w~ll as. cultural constraints. Elimination of stray dogs IS not an effIcIent means of controllIng eIther the dog population or rabies, but it may create public awarenes

Densities and phase equilibria of hydrogen, propane and vegetable oil mixtures. Experimental data and thermodynamic modeling

Heterogeneous catalytic gas-liquid reactions are intensified when carried out in the homogenous fluid phase by means of a supercritical co-solvent. For instance, supercritical propane is used to enhance yield in the hydrogenation of vegetable oils. Besides phase equilibrium knowledge, volumetric information is also needed to elucidate kinetic mechanisms and design continuous supercritical reactors. In this work, we report new experimental PvT data of the reactive mixture H2+sunflower oil+propane using the isochoric method. In addition, the phase equilibria and PvT data are modeled with the GCA and RK-PR equations of state, respectively. The isochoric method not only provides PvT information under the reaction conditions, but also the reactive system compressibility, key variable to attain enhanced transport properties in the supercritical reactors.Fil: Hegel, Pablo Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Cotabarren, Natalia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Brignole, Esteban Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Pereda, Selva. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina. University of KwaZulu-Natal; Sudáfric

Microsatellite primers for the four Galápagos mockingbird species (Mimus parvulus, Mimus macdonaldi, Mimus melanotis and Mimus trifasciatus)

Nineteen di- and tetranucleotide and one trinucleotide microsatellite DNA markers were isolated from the Galapagos mockingbird (Mimus parvulus) and tested for cross-species amplification in the other three mockingbird species in the Galapagos. In addition, primers for two microsatellite loci previously developed for Mimus polyglottos were redesigned to obtain shorter amplification fragments. The number of alleles per locus and species ranged from 1 to 8, and expected heterozygosity varied from 0.0 to 0.809. These microsatellite markers will be useful to study levels of inbreeding in different island populations

Predictive Spatial Dynamics and Strategic Planning for Raccoon Rabies Emergence in Ohio

Rabies is an important public health concern in North America because of recent epidemics of a rabies virus variant associated with raccoons. The costs associated with surveillance, diagnostic testing, and post-exposure treatment of humans exposed to rabies have fostered coordinated efforts to control rabies spread by distributing an oral rabies vaccine to wild raccoons. Authorities have tried to contain westward expansion of the epidemic front of raccoon-associated rabies via a vaccine corridor established in counties of eastern Ohio, western Pennsylvania, and West Virginia. Although sporadic cases of rabies have been identified in Ohio since oral rabies vaccine distribution in 1998, the first evidence of a significant breach in this vaccine corridor was not detected until 2004 in Lake County, Ohio. Herein, we forecast the spatial spread of rabies in Ohio from this breach using a stochastic spatial model that was first developed for exploratory data analysis in Connecticut and next used to successfully hind-cast wave-front dynamics of rabies spread across New York. The projections, based on expansion from the Lake County breach, are strongly affected by the spread of rabies by rare, but unpredictable long-distance translocation of rabid raccoons; rabies may traverse central Ohio at a rate 2.5-fold greater than previously analyzed wildlife epidemics. Using prior estimates of the impact of local heterogeneities on wave-front propagation and of the time lag between surveillance-based detection of an initial rabies case to full-blown epidemic, specific regions within the state are identified for vaccine delivery and expanded surveillance effort

Variation in host home range size decreases rabies vaccination effectiveness by increasing the spatial spread of rabies virus

Animal movement influences the spatial spread of directly transmitted wildlife disease through host-host contact structure. Wildlife disease hosts vary in home range- associated foraging and social behaviours, which may increase the spread and intensity of disease outbreaks. The consequences of variation in host home range movement and space use on wildlife disease dynamics are poorly understood, but could help to predict disease spread and determine more effective disease management strategies. We developed a spatially explicit individual-based model to examine the effect of spatiotemporal variation in host home range size on the spatial spread rate, persistence and incidence of rabies virus (RABV) in raccoons (Procyon lotor). We tested the hypothesis that variation in home range size increases RABV spread and decreases vaccination effectiveness in host populations following pathogen invasion into a vaccination zone. We simulated raccoon demography and RABV dynamics across a range of magnitudes and variances in weekly home range size for raccoons. We examined how variable home range size influenced the relative effectiveness of three components of oral rabies vaccination (ORV) programmes targeting raccoons—timing and frequency of bait delivery, width of the ORV zone and proportion of hosts immunized. Variability in weekly home range size increased RABV spread rates by 1.2-fold to 5.2-fold compared to simulations that assumed a fixed home range size. More variable host home range sizes decreased relative vaccination effectiveness by 71% compared to less variable host home range sizes under conventional vaccination conditions. We found that vaccination timing was more influential for vaccination effectiveness than vaccination frequency or vaccination zone width. Our results suggest that variation in wildlife home range movement behaviour increases the spatial spread and incidence of RABV. Our vaccination results underscore the importance of prioritizing individual-level space use and movement data collection to understand wildlife disease dynamics and plan their effective control and elimination

Long-term trends in hepatitis C prevalence, treatment uptake and liver-related events in the Swiss HIV Cohort Study

BACKGROUND AND AIMS: Treatment for chronic hepatitis C virus (HCV) infections changed dramatically in the last decade. We assessed changes in the prevalence of replicating HCV infection, treatment uptake and liver-related morbidity and mortality in persons with HIV (PWH) and hepatitis C in the Swiss HIV cohort study. METHODS: We included all cohort participants between 2002 and 2021. We assessed yearly prevalence of replicating HCV infection, overall and liver-related mortality, as well as the yearly incidence of liver-related events in persons with at least one documented positive HCV-RNA. RESULTS: Of 14 652 participants under follow-up, 2294 had at least one positive HCV-RNA measurement. Of those, 1316 (57%) ever received an HCV treatment. Treatment uptake increased from 8.1% in 2002 to a maximum of 32.6% in 2016. Overall, prevalence of replicating HCV infection declined from 16.5% in 2004 to 1.3% in 2021. HCV prevalence declined from 63.2% to 7.1% in persons who inject drugs, and from 4.1% to 0.6% in men who have sex with men. Among the 2294 persons with replicating HCV infection, overall mortality declined from a maximum of 3.3 per 100 patient-years (PY) to 1.1 per 100 PY, and incidence of liver-related events decreased from 1.4/100 PY to 0.2/100 PY. CONCLUSIONS: The introduction of DAA therapy was associated with a more than 10-fold reduction in prevalence of replicating HCV infection in PWH, approaching the estimates in the general population. Overall mortality and liver-related events declined substantially in persons living with HIV and hepatitis C

Screening for Hepatocellular Carcinoma among adults with HIV/Hepatitis B coinfection in Zambia: A Pilot Study

Background & aims: Chronic hepatitis B virus (HBV) infection is the main cause of hepatocellular carcinoma (HCC) in sub-Saharan Africa (SSA). In an established cohort of HIV/HBV-coinfected individuals on antiretroviral therapy (ART), we piloted an HCC screening initiative at two outpatient clinics in Lusaka, Zambia. Methods: We performed abdominal ultrasound (AUS) and transient elastography in all patients. Results: Among 279 HIV/HBV-coinfected patients, 165 (59.1%) were men, median age was 34 years (interquartile range 28-39) and median CD4 count 246 cells/µl (112-355). While 102 (36.6%) individuals had elevated transaminases, 114 (40.9%) had HBV levels >2000 IU/mL and 59 (24.6%) significant fibrosis. On AUS, 75 (26.9%) participants had hepatomegaly and 69 (24.7%) peri-portal fibrosis. Five patients had a liver lesion >1cm, an indication for confirmatory imaging. Conclusions: In one of the first HCC screening initiatives in SSA, 2% of HIV/HBV-coinfected adults had significant liver lesions, and a quarter had findings suggestive of schistosomiasis-induced liver damage