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Rift Valley fever – a growing threat to humans and animals
2021
Kwaśnik Małgorzata | Rożek Wojciech | Rola Jerzy
Rift Valley fever (RVF) is a zoonotic, vector-borne infectious disease of ruminants and camels transmitted mainly by the Aedes and Culex mosquito species. Contact with the blood or organs of infected animals may infect humans. Its etiological factor is the Rift Valley fever virus (RVFV) of the Phlebovirus genus and Bunyaviridae family. Sheep and goats are most susceptible to infection and newborns and young individuals endure the most severe disease course. High abortion rates and infant mortality are typical for RVF; its clinical signs are high fever, lymphadenitis, nasal and ocular secretions and vomiting. Conventional diagnosis is done by the detection of specific IgM or IgG antibodies and RVFV nucleic acids and by virus isolation. Inactivated and live-attenuated vaccines obtained from virulent RVFV isolates are available for livestock. RVF is endemic in sub-Saharan Africa and the Arabian Peninsula, but in the last two decades, it was also reported in other African regions. Seropositive animals were detected in Turkey, Tunisia and Libya. The wide distribution of competent vectors in non-endemic areas coupled with global climate change threaten to spread RVF transboundarily. The EFSA considers the movement of infected animals and vectors to be other plausible pathways of RVF introduction into Europe. A very low risk both of introduction of the virus through an infected animal or vector and of establishment of the virus, and a moderate risk of its transmission through these means was estimated for Poland. The risk of these specific modes of disease introduction into Europe is rated as very low, but surveillance and response capabilities and cooperation with the proximal endemic regions are recommended.
Показать больше [+] Меньше [-]Validation of an ELISA for the concurrent detection of total antibodies (IgM and IgG) to Rift Valley fever virus
2014
Charlotte E. Ellis | Vuyokazi E. Mareledwane | Roy Williams | David B. Wallace | Phelix A.O. Majiwa
Rift Valley fever virus (RVFV) infects humans and livestock, causing haemorrhaging andabortions in animals. Three major RVF epizootics have occurred in South Africa since the1950s and the outbreak in 2010 had a mortality rate of 10.7% in humans. Accurate and earlydetection is therefore essential for management of this zoonotic disease. Enzyme-linkedimmunosorbent assays (ELISAs) have been developed for the detection of either IgM or IgGantibodies to RVFV in animal sera. In this study, data are presented on the validation of adouble-antigen ELISA for the simultaneous detection of both classes of antibodies to RVFV ina single test. ELISA plates were coated with a recombinant nucleoprotein. The nucleoprotein,conjugated to horseradish peroxidase, was used as the detecting reagent. A total of 534 serafrom sheep and cattle were used in the validation. The sheep sera were collected during a RVFpathogenesis study at the Agricultural Research Council (ARC) – Onderstepoort VeterinaryInstitute and the cattle sera were collected during an outbreak of RVF in 2008 at the ARC –Animal Production Institute in Irene, Pretoria. The ELISA had a diagnostic sensitivity of 98.4%and a specificity of 100% when compared to a commercial cELISA. This convenient and fastassay is suitable for use in serological surveys or monitoring immune responses in vaccinatedanimals.
Показать больше [+] Меньше [-]Nanoparticles as Immune Modulatory Reagents for Production of Rift Valley Fever Hyperimmune Serum in Sheep
2023
Marwa Yehia H | Diana M. Abulmagd | Mohamed H. Atwa | Noha Ezz El-Deen | Taradi Abd El-Fattah
Rift Valley Fever (RVF) since its discovery has been recognized as a source of numerous outbreaks in Africa and Arab peninsulas. It is a zoonotic highly pathogenic mosquito born virus disease. The first line of defense against such disease is the prevention of its the occurrence by periodic vaccination. The use of adjuvant is of fundamental importance in vaccines formulations and hyperimmune serum production. This study aimed to prepare hyperimmune serum against RVF virus to be used in diagnostic purposes in addition to its possible use for treatment in emergence cases. To establish this goal, we use Montanide IMS 3015 investigating its immune modulatory effect in immunized sheep. The experimental sheep received 3 injections of inactivated RVF virus adjuvant with Montanide IMS 3015 one week intervals, the fourth injection was virulent virus. The obtained serum 7 days after the last injection was discovered to be safe and free of foreign pollutants. For mice; specific for RVF virus with mean serum neutralizing antibody titer 20480 and ELISA optical density 1.402. It was found that this serum was able to protect mice against experimental infection with RVF virus in the ratios 100%; 100%; 90% and 60% of it was administrated to mice 24 hours pre-virus infection; simultaneously with the virus; 24 hours post-infection and 48 hours post infection respectively while later serum administration was unable to protect mice against viral infection.
Показать больше [+] Меньше [-]A review of the infectious diseases of African wild ruminants
2001
Worthington, R.W. | Bigalke, R.D.
Could bats act as reservoir hosts for Rift Valley fever virus?
1999
Oelofsen, M.J. | Van der Ryst, E. (Orange Free State Univ., Bloemfontein (South Africa). Dept. of Virology)
Distribution of viral antigen in tissues of new-born lambs infected with Rift Valley fever virus
1996
Van der Lugt, J.J. (Agricultural Research Council, Onderstepoort (South Africa). Onderstepoort Veterinary Inst.) | Coetzer, J.A.W. | Smit, M.M.E.
The use of sucrose-acetone-extracted Rift Valley fever virus antigen derived from cell culture in an indirect enzyme-linked immunosorbent assay and haemagglutination-inhibition test
1995
Paweska, J.T. | Barnard, B.J.H. | Williams, R. (Agricultural Research Council, Onderstepoort (South Africa). Onderstepoort Veterinary Inst.)
Indirect enzyme-linked immunosorbent assay for the detection of antibody against Rift Valley fever virus in domestic and wild ruminant sera
2003
Paweska, J.T. | Smith, S.J. | Wright, I.M. | Williams, R. | Cohen, A.S. (Agricultural Research Council, Onderstepoort (South Africa). Onderstepoort Veterinary Inst.) | Van Dijk, A.A. | Grobbelaar, A.A. | Croft, J.E. | Swanepoel, R. | Gerdes, G.H.
Teratogenicity of a mutagenised Rift Valley fever virus (MVP 12) in sheep
2002
Hunter, P. (Onderstepoort Biological Products Ltd. (South Africa)) | Erasmus, B.J. | Vorster, J.H.
Development of a diagnostic one-tube RT-PCR for the detection of Rift Valley fever virus
2002
Espach, A. | Romito, M. (Agricultural Research Council, Onderstepoort (South Africa). Onderstepoort Veterinary Inst.) | Nel, L.H. | Viljoen, G.J.