Search results for "General Veterinary"
showing 10 items of 334 documents
Fascioliasis in Llama, Lama glama, in Andean Endemic Areas: Experimental Transmission Capacity by the High Altitude Snail Vector Galba truncatula and…
2021
Simple Summary The infection by the liver fluke Fasciola hepatica in South American camelids, mainly llamas and alpacas, has been the focus of many studies. However, their capacity to participate in the transmission of the disease and their potential reservoir role in human or animal endemic areas have never been studied. Therefore, all development stages of an isolate from Argentine llama of the high Andean plateau have been experimentally investigated, from egg embryogenesis to metacercarial infectivity, by using the vector snail Galba truncatula from the high altitude Bolivian Altiplano human hyperendemic area. Although eggs shed by llamas may successfully develop until the adult stage i…
Relationships between host species and morphometric patterns in Fasciola hepatica adults and eggs from the northern Bolivian Altiplano hyperendemic r…
2001
The highest prevalences and intensities of human fasciolosis by Fasciola hepatica are found in the northern Bolivian Altiplano, where sheep and cattle are the main reservoir host species and pigs and donkeys the secondary ones. Morphometric comparisons of many linear measurements, areas and ratios of F. hepatica adults (from sheep, cattle and pigs) and eggs (from sheep, cattle, pigs and donkeys) in natural liver fluke populations of the Bolivian Altiplano, as well as of F. hepatica adults and eggs experimentally obtained in Wistar rats infected with Altiplanic sheep, cattle and pig isolates, were made using computer image analysis and an allometric model. Although morphometric values of adu…
Developmental differences in the uterus of Fasciola hepatica between livestock liver fluke populations from Bolivian highlands and European lowlands
2001
A morphometric study of the uterus area (UA) of Fasciola hepatica adults was carried out with the aid of a computer linked to a stereomicroscopic 3CCD colour video camera using image analysis software. The UA of adult liver flukes found in naturally infected sheep, cattle and pig from the endemic human fascioliasis zone of the northern Bolivian Altiplano highlands was compared with that of flukes found infecting sheep and cattle from Valencia, Spain and cattle from Corsica, France (collectively, European lowlands). Liver fluke UA was examined using an allometric model. A comparison of the allometry of the liver fluke UA in different host species from Bolivia revealed no significant differen…
Aplicação do conceito One Health na área hiperendêmica de fasciolíase humana do Altiplano Boliviano: biologia dos limneídeos, dinâmica populacional, …
2021
Abstract Fascioliasis is a freshwater snail-borne zoonotic disease. The Northern Bolivian Altiplano is a very high altitude endemic area where the highest human prevalences and intensities have been reported. Preventive chemotherapy by treatment campaigns is yearly applied. However, liver fluke infection of cattle, sheep, pigs and donkeys assures endemicity and consequent human infection and re-infection risks. A One Health action has therefore been implemented. Activity concerns lymnaeid vectors and environment diversity. Studies included growth, egg-laying and life span in laboratory-reared lymnaeids. Different habitat types and influencing factors were assessed. All populations proved to…
Sheep and Cattle Reservoirs in the Highest Human Fascioliasis Hyperendemic Area: Experimental Transmission Capacity, Field Epidemiology, and Control …
2020
The Northern Bolivian Altiplano is the human fascioliasis hyperendemic area where the highest prevalences and intensities of infection by Fasciola hepatica in humans have been reported. Four animal species are the reservoir species for F. hepatica in this area, namely, sheep, cattle, pigs, and donkeys. Livestock for the Aymara inhabitants is crucial because vegetable cultures are not viable due to the inhospitality of the very high altitude of 3,820–4,100 m. A One Health initiative has been implemented in this area in recent years, as the first such control action in a human endemic area ever. Among the different control axes included, special focus is devoted to the two main reservoirs she…
Persistence of protection through 33 months of age provided by immunization in infancy with two three-component acellular pertussis vaccines
1998
Abstract A large, randomized, placebo-controlled clinical trial in Italy on two three-component pertussis vaccines, given as DTaP in infancy, one manufactured by SmithKline and Beecham (SB) and one by Chiron Biocine (CB), found each vaccine to be 84% efficacious through the average age of 24 months. The cohort of children envolled in the trial was followed with unmodified case ascertainment procedures for nine additional calendar months, during which partial unblinding occurred, for the unvaccinated randomized group. For the DTaP groups, the specific vaccine assignment remained double-blinded throughout the entire additional observation period. Pertussis was defined as paroxysmal cough last…
Analogous IgG subclass response to pertussis toxin in vaccinated children, healthy or affected by whooping cough
2003
The study of antigen specific IgG subclass distribution during disease, or during any other natural or artificial immunisation, can provide useful information on the kind of the immune response and the expected levels of protection. This is particularly true for diseases, such as pertussis in which the mechanisms underlying specific defence are still not completely understood. An investigation was therefore performed to evaluate the IgG subclass response to pertussis toxin (PT) in sera from 89 healthy vaccinated children and 131 vaccinated or unvaccinated children convalescent after a confirmed B. pertussis symptomatic infection. Antibody titres were expressed in arbitrary ELISA units/ml, a…
Protein-prime/modified vaccinia virus Ankara vector-boost vaccination overcomes tolerance in high-antigenemic HBV-transgenic mice
2015
Abstract Background Therapeutic vaccination is a novel treatment approach for chronic hepatitis B, but only had limited success so far. We hypothesized that optimized vaccination schemes have increased immunogenicity, and aimed at increasing therapeutic hepatitis B vaccine efficacy. Methods Modified Vaccinia virus Ankara (MVA) expressing hepatitis B virus (HBV) antigens was used to boost protein-prime vaccinations in wildtype and HBV-transgenic (HBVtg) mice. Results Protein-prime/MVA-boost vaccination was able to overcome HBV-specific tolerance in HBVtg mice with low and medium but not with high antigenemia. HBV-specific antibody titers, CD8+ T-cell frequencies and polyfunctionality inverse…
Timing of activation of CD4+ memory cells as a possible marker to establish the efficacy of vaccines against contagious agalactia in sheep
2013
Mycoplasma agalactiae is a major pathogen of sheep and goats in many areas of the world and particularly in Mediterranean countries. It causes contagious agalactia, an infectious disease primarily affecting mammary glands. Many vaccines against the pathogen are currently under development. The aim of the study was to investigate the involvement of T cell-mediated immunity during vaccination and challenge experiments against Mycoplasma agalactiae. A comparison of the antigen-specific expansion of interferon gamma positive T cell memory and naïve subsets was performed between vaccinated and non-vaccinated sheep to identify cellular subsets whose activation was different between protected and …
Adoptive transfer of protective immunity from Cryptosporidium parvum-infected interferon-gamma and interleukin-12-deficient mice to naive recipients.
2008
We investigated the possibility of transfer immunity from Cryptosporidium parvum-infected interferon-gamma (GKO) and interleukin-12p40 (IL-12KO) deficient C57BL/6 mice to naive mice by transfer of intraepithelial lymphocytes (IELs) and CD4(+) T cells from spleen and mesenteric lymph nodes (MLNs). Three days after the transfer recipients were infected with C. parvum. IELs isolated from GKO donor mice after resolution of infection (day 15) but not at the peak of infection (day 8) significantly reduced the parasite load in recipient mice. In IL-12KO mice, IELs and also CD4(+) T cells isolated from the spleen and MLNs of donor mice at the peak of infection (day 5) and after resolution (day 15) …