Rift Valley fever (RVF) is a vector-borne disease transmitted by a broad spectrum of mosquito species, especially Aedes and Culex genus, to animals (domestic and wild ruminants and camels) and humans. Rift Valley fever is endemic in sub-Saharan Africa and in the Arabian Peninsula, with periodic epidemics characterised by 5-15 years of inter-epizootic periods. In the last two decades, RVF was notified in new African regions (e.g. Sahel), RVF epidemics occurred more frequently and low-level enzootic virus circulation has been demonstrated in livestock in various areas. Recent outbreaks in a French overseas department and some seropositive cases detected in Turkey, Tunisia and Libya raised the attention of the EU for a possible incursion into neighbouring countries. The movement of live animals is the most important pathway for RVF spread from the African endemic areas to North Africa and the Middle East. The movement of infected animals and infected vectors when shipped by flights, containers or road transport is considered as other plausible pathways of introduction into Europe. The overall risk of introduction of RVF into EU through the movement of infected animals is very low in all the EU regions and in all MSs (less than one epidemic every 500 years), given the strict EU animal import policy. The same level of risk of introduction in all the EU regions was estimated also considering the movement of infected vectors, with the highest level for Belgium, Greece, Malta, the Netherlands (one epidemic every 228-700 years), mainly linked to the number of connections by air and sea transports with African RVF infected countries. Although the EU territory does not seem to be directly exposed to an imminent risk of RVFV introduction, the risk of further spread into countries neighbouring the EU and the risks of possible introduction of infected vectors, suggest that EU authorities need to strengthen their surveillance and response capacities, as well as the collaboration with North African and Middle Eastern countries.
Introduction: Rift Valley Fever (RVF) has caused outbreaks in Africa, impacting human health and animal trade. Recently, sporadic detections among humans and animals in East Africa have replaced large-scale outbreaks. We assessed RVF knowledge levels in East and Central Africa across countries with different epidemiological profiles.
Oropouche fever, a mosquito- or midge-borne emerging zoonotic disease endemic to South and Central America, manifests as a dengue-like acute febrile illness with occasional occurrences of meningitis or meningoencephalitis. The causative agent, Oropouche virus (OROV), belongs to the genus Orthobunyavirus within the family Peribunyaviridae. Its tripartite negative-sense RNA genome comprises small (S), medium (M), and large (L) segments, encoding structural N, Gn/Gc, and L proteins, respectively.
High-density suspension cultures of insect cells offer a scalable and serum-free system for the expression of recombinant proteins. Rift Valley fever virus (RVFV), an arthropod-borne virus spread by mosquitoes, contains two envelop glycoproteins Gn and Gc. These glycoproteins are crucial for eliciting neutralizing antibodies that can offer protection against RVFV infection.
Faculty of Veterinary Medicine, Department of Pathology, Fundamental and Applied Research for Animals and Health (FARAH), University of Liège, Liège, Belgium.
The recombinant expression and purification of viral proteins are a key component in the study of the immune response of viruses, as well as the creation of diagnostic techniques for the detection of viruses. For structurally simple proteins, one commonly used technique is the production of recombinant proteins in bacterial expression systems, which enable the large-scale synthesis and purification of recombinant viral proteins. In this technique, the cDNA encoding for a viral protein is cloned into a bacterial expression vector (with an appropriate purification tag), produced in a modified bacterial culture, and optimized for maximum protein production in a minimal amount of time.
