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Arthropod-borne virus encephalitis
Published in Avindra Nath, Joseph R. Berger, Clinical Neurovirology, 2020
The epidemiology of Rift Valley fever virus (RVFV) is remarkable for the wide spectrum of vertebrate hosts and mosquito vectors, and also for the several mechanisms by which humans can be infected (Table 16.12). These include the bite of an infected vector, handling of carcasses, tissues or abortuses of infected animals, and the aerosol route. Torrential rainfall, flooded agricultural plains and irrigation canals serve as breeding sites for vectors. A review of published material from 1931 through 2015 highlighted the consumption of animal products, contact with infected animals and residing in low altitude areas associated with favorable climatic and ecological conditions for emergence of Rift Valley fever [171]. RVFV is one of the infectious agents for which satellite imaging is useful to determine locations that would support viral transmission. Several such areas were identified by serial surveys and satellite data in the 2000 outbreak in Yemen [172].
The Pathogenesis and Pathology of the Hemorrhagic State in Viral and Rickettsial Infections
Published in James H. S. Gear, CRC Handbook of Viral and Rickettsial Hemorrhagic Fevers, 2019
Rift Valley fever virus is transmitted to sheep by mosquitoes in African enzootics. Human Rift Valley fever (RVF) is usually an influenza-like illness of short duration with abrupt onset of chills, fever, headache, retroorbital pain, myalgia, anorexia, vomiting, and diarrhea.41,42 Physical signs include fever, facial erythema, conjunctival suffusion, and (rarely) cutaneous petechiae. Blood pressure, liver function tests, platelet count, and prothrombin time are normal. A small portion of infected patients develop visual retinal lesions, severe hemorrhagic diathesis, or late onset of encephalitis.
Ribavirin
Published in M. Lindsay Grayson, Sara E. Cosgrove, Suzanne M. Crowe, M. Lindsay Grayson, William Hope, James S. McCarthy, John Mills, Johan W. Mouton, David L. Paterson, Kucers’ The Use of Antibiotics, 2017
Emily Woolnough, Amanda Wade, Joe Sasadeusz
Rift Valley fever virus and sandfly fever virus are less susceptible than other Bunyaviridae, with EC50 values determined by plaque reduction of 75–80 μg/ml (Huggins, 1989; Watts et al., 1989). However, in rodents and monkeys infected with Rift Valley fever virus, ribavirin therapy has produced a survival benefit (Huggins, 1989), and ribavirin prophylaxis prevented disease in hamsters (Peters et al., 1986).
Infravec2 guidelines for the design and operation of containment level 2 and 3 insectaries in Europe
Published in Pathogens and Global Health, 2023
Emilie Pondeville, Anna-Bella Failloux, Frederic Simard, Petr Volf, Andrea Crisanti, Roya Elaine Haghighat-Khah, Núria Busquets, Francesc Xavier Abad, Anthony J Wilson, Romeo Bellini, Sarah Marsh Arnaud, Alain Kohl, Eva Veronesi
For arboviruses, it is recommended not to enter insectaries for a week following return from areas where pathogens, which can be transmitted by vectors in the facility, are endemic or currently being transmitted. If no symptoms are present after this point, the workers may reenter the facility. Self-monitoring is essential, and potentially medical investigation if infection is suspected (for example, after bites, length of stay in affected area, etc.). When working with animal pathogens (e.g. Rift Valley fever virus), it may be recommended not to visit facilities with potentially susceptible animals following experiments for a duration that should be decided on a virus-specific risk assessment basis. Such assessments should be carried out for pathogens and insect species to be studied at each location on a case-by-case basis.
The role of plant expression platforms in biopharmaceutical development: possibilities for the future
Published in Expert Review of Vaccines, 2019
Another emerging One Health disease threat is Rift Valley fever virus (RVFV), transmitted to livestock and humans in Africa and on the Arabian Penninsula by mosquitoes and responsible for hemorrhagic fever symptoms and miscarriages. Human vaccines are not currently available and vaccines for animals cannot readily be distributed in these areas. Mbewana et al. (2018) have generated chimeric RVFV virus-like particles in Nicotiana benthamiana using transient Agrobacterium tumefaciens-mediated infiltration [45]. The authors were able to construct a chimera consisting of the outer region of the spike glycoprotein of RVFV fused to the transmembrane domain and cytosolic tail-encoding region of the hemagglutinin (HA) of avian influenza H5N1. Using electron microscopy, the authors were able to identify 49–60 nm virus-like particles composed of these RVFV-HA chimeras that were able to elicit a strong antibody response against RVFV without the need for an adjuvant. The nucleoprotein (N) and a deletion mutant of the Gn protein of RVFV have also been generated in transgenic Arabidopsis thaliana plants and tested for immunogenicity using mice by oral administration [46]. The fact that an immune response was reported for mice fed transgenic lines offers promise for the production of a plant-made vaccine against RVFV.
Prevalence and identification of arthropod-transmitted viruses in Kassala state, Eastern Sudan
Published in Libyan Journal of Medicine, 2019
Nahla Mohamed, Mamoun Magzoub, Rania El Hadi Mohamed, Fadilah Sfouq Aleanizy, Fulwah Y. Alqahtani, Bakri Y. M. Nour, Mubark M.S. Alkarsany
In the present study, we observed that the most common symptoms were fever, followed by headache, nausea, vomiting, and abdominal pain which are not restricted to only RVFV, CHIKV, and SINV infections, previous studies shown that infection with chikungunya and Sindbis viruses characterize by specific symptoms such as skin rash, myalgia, and arthralgia. The degree of the infection based on the severity of nausea and vomiting, skin rashes, and abdominal pain differed significantly between adults and children, which could be explained by the fact that most participants were adults. Considering the variations in symptoms, efficient and accurate diagnostic methods for these viral diseases are urgently required.