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Survey of Rift Valley Fever Virus Antibodies and Risk Factors in Small Ruminants in Maiduguri, Borno State, Nigeria: A Cross-Sectional Serological Study.

BACKGROUND: Rift Valley fever (RVF) is a zoonotic viral disease transmitted through mosquito bites commonly reported in low- to medium-income countries such as Nigeria. It impacts livestock productivity and trade, causing abortions and high rates of mortality, particularly among young animals. OBJECTIVES: A cross-sectional study was aimed to determine the presence of RVF virus antibodies (anti-RVFV IgG antibodies) and to identify related risk factors in small ruminants within Maiduguri Metropolis, Borno State, Nigeria. METHODS: Ninety-six blood samples were collected; information on species,…

BTX-A51 treatment modulates host innate immune responses via NF-κB and β-catenin signaling during Rift Valley fever virus infection in vitro.

Rift Valley fever virus (RVFV) is a zoonotic and mosquito-borne hemorrhagic pathogen of high pandemic potential, endemic to most countries in Africa. It most severely causes disease in small domestic ruminants and is transmitted to humans. RVFV has been declared a priority pathogen by the World Health Organization for vaccine and therapeutic development. Outbreaks of this virus are known to cause great disturbances to the economy, agriculture, food availability, and healthcare system of local communities. No U.S. FDA-approved vaccines or therapeutics exist for the prevention or treatment of RV…

Spatio-temporal dynamics of Rift Valley fever virus circulation in sentinel livestock herds (2021-2024) before the initial fatal human outbreaks in Senegal.

BACKGROUND: Multiple detections of Rift Valley fever virus (RVFV) infections in humans, animals and mosquito vectors suggest permanent circulation of RVFV in Senegal. This study investigated the spatial and temporal dynamics of RVFV circulation in central (Sahelian) and southeastern (Sudanian) Senegal from March 2021 to June 2024. METHODS: A total of 976 initially seronegative sheep and goats from sentinel herds in 10 districts and 2 areas were monitored for 40 months. Serum samples were collected quarterly and tested by ELISA, while mosquitoes were collected monthly and screened for RVFV RNA…

A Novel BoHV-1-Vectored Subunit RVFV Vaccine Induces a Robust Humoral and Cell-Mediated Immune Response Against Rift Valley Fever in Sheep.

Rift Valley fever (RVF) is a vector-borne zoonotic viral disease that causes abortion storms, fetal malformations, and neonatal mortality in livestock ruminants. In humans, RVF can lead to hemorrhagic fever, encephalitis, retinitis, or blindness, and about 1% of patients die. Since there are no registered vaccines for human use, developing RVF vaccines for use in animals is crucial to protect animals and prevent the spread of the virus from infecting humans. We recently developed a live bovine herpesvirus type 1 quadruple gene-mutant vector (BoHV-1qmv) that lacks virulence and immunosuppressiv…

Development of a Simian RNA Polymerase I Promoter-Driven Reverse Genetics for the Rescue of Recombinant Rift Valley Fever Virus from Vero Cells.

Rift Valley fever (RVF), which has been designated as a priority disease by the World Health Organization (WHO), is one of the most pathogenic zoonotic diseases endemic to Africa and the Arabian Peninsula. Human vaccine preparation requires the use of appropriate cell substrates to support efficient production of seed vaccine with minimum concerns of tumorigenicity, oncogenicity, or adventitious agents. Vero cells, which were derived from the African green monkey kidney, represent one of the few mammalian cell lines that are used for vaccine manufacturing. This study demonstrated the rescue of…

Мониторинг антивирусного потенциала яда пчелиных ядов и восковых экстрактов на основе моделей вирусов Адено-7 (ДНК) и Вируса лихорадки Рифт-Вэлли (РНК).

В ходе этого исследования отслеживался антивирусный потенциал яда пчел и четырех восковых экстрактов, белого этанола и черного пчелиного воска (EWW/EBW) и ацетона белого и черного пчелиного (AWW/ABW). Две различные вирусные модели, а именно Adeno-7 в качестве модели ДНК и RVFV в качестве RNA-вирусных моделей. Расчет конечной точки был использован для расчета истощения вируса. В результате истощения вирусного инфекционного титера от ABW до Adeno-7 была зарегистрирована сильная антивирусная активность, которая привела к истощению вирусного инфекционного титера (1,66 log (10)/млл), что дало равны

Cross-sectional survey of Rift Valley fever virus exposure in Bodhei village located in a transitional coastal forest habitat in Lamu county, Kenya.

Few studies have focused on Rift Valley fever virus (RVFV) transmission in less arid, transitional landscapes surrounding known high-risk regions. The objective of this study was to identify evidence of RVFV exposure in Bodhei Village in a forested area at the edge of the RVFV-epidemic Garissa region. In a household cluster-based survey conducted between epidemics in early 2006, 211 participants were enrolled. Overall seroprevalence for anti-RVFV was high (18%) and comparable with rates in the more arid, dense brush regions farther north. Seroprevalence of adults was 28%, whereas that of child…

Comparison of sampling techniques for Rift Valley Fever virus potential vectors, Aedes aegypti and Culex pipiens complex, in Ngorongoro District in northern Tanzania.

We investigated mosquito sampling techniques with two types of traps and attractants at different time for trapping potential vectors for Rift Valley Fever virus. The study was conducted in six villages in Ngorongoro district in Tanzania from September to October 2012. A total of 1814 mosquitoes were collected, of which 738 were collected by CDC light traps and 1076 by Mosquito Magnet trapping technique. Of the collected mosquitoes, 12.46% (N = 226) were Aedes aegypti and 87.54% (N = 1588) were Culex pipiens complex. More mosquitoes were collected outdoors using Mosquito Magnets baited with oc…

A 3-year serological and virological cattle follow-up in Madagascar highlands suggests a non-classical transmission route of Rift Valley fever virus.

Rift Valley fever virus (RVFV) is a mosquito-borne infection of livestock and human which causes a potentially severe disease. In 2008-2009, a RVF outbreak occurred in a temperate and mountainous area located on the highlands of Madagascar. A three-year cattle follow-up (2009-2011) was conducted in a pilot area of this highland. A seroprevalence rate of 28% was estimated in 2009 and a seroconversion rate of 7% in 2009-2010. A third cross-sectional survey showed a seroconversion rate of 14% in 2010-2011. In 2011 the longitudinal study suggested a RVFV circulation during the year. In this area w…

Доминирующее отрицательное сдерживание двойного белкового киназа РНК PKR повышает эффективность вакцины MP-12 от вируса лихорадки Рифт-Вэлли.

Вирус лихорадки Рифт-Вэлли (RVFV), относящийся к роду Флебовирус, семейству Буньявиридае, эндемичен для стран Африки к югу от Сахары и вызывает высокий уровень абортов у румян и геморрагической лихорадки, энцефалита или слепоты у людей. MP-12 является единственным штаммом RVFV, исключенным из правила отбора агентов и обрабатываемым на уровне 2 (BSL2). MP-12 кодирует функциональный основной коэффициент вирулентности, NS-белок, который способствует его остаточной вирулентности у беременных овец. Мы обнаружили, что 100% мышей, прошедших подкожную вакцинацию с помощью рекомбинантного MP-12 (rMP12)

Совпадение в аннотации оригинала
Rift Valley fever virus (RVFV), belonging to the genus Phlebovirus, family Bunyaviridae, is endemic to sub-Saharan Africa and causes a high rate of abortion in ruminants and hemorrhagic fever, encephalitis, or blindness in humans. MP-12 is the only RVFV strain excluded from the select-agent rule and handled at a biosafety level 2 (BSL2) laboratory. MP-12 enc…

Multiple virus lineages sharing recent common ancestry were associated with a Large Rift Valley fever outbreak among livestock in Kenya during 2006-2007.

Rift Valley fever (RVF) virus historically has caused widespread and extensive outbreaks of severe human and livestock disease throughout Africa, Madagascar, and the Arabian Peninsula. Following unusually heavy rainfall during the late autumn of 2006, reports of human and animal illness consistent with RVF virus infection emerged across semiarid regions of the Garissa District of northeastern Kenya and southern Somalia. Following initial RVF virus laboratory confirmation, a high-throughput RVF diagnostic facility was established at the Kenyan Central Veterinary Laboratories in Kabete, Kenya, t…

Rift Valley fever virus lacking NSm proteins retains high virulence in vivo and may provide a model of human delayed onset neurologic disease.

Rift Valley fever virus is a significant human and veterinary pathogen responsible for explosive outbreaks throughout Africa and the Arabian Peninsula. Severe acute disease in humans includes rapid onset hepatic disease and hemorrhagic fever or delayed onset encephalitis. A highly efficient reverse genetics system was developed which allowed generation of recombinant RVF viruses to assess the role of NSm protein in virulence in a rat model in which wild-type RVF virus strain ZH501 (wt-ZH501) results in 100% lethal hepatic disease 2-3 days post infection. While extensive genomic analysis indica…

The prevalence of antibody to the viruses of bovine virus diarrhoea, bovine herpes virus 1, rift valley fever, ephemeral fever and bluetongue and to Leptospira sp in free-ranging wildlife in Zimbabwe.

The prevalence of antibody to the viruses of bovine virus diarrhoea (BVD), bovine herpes virus typel (BHV1), rift valley fever (RVF), bovine ephemeral fever (BEF) and bluetongue (BT) and to Leptospira sp. was determined in wildlife populations in Zimbabwe. Evidence of infection with BVD virus was found in 14 of the 16 species examined but was greatest in eland Taurotragus oryx, nyala Tragelaphus angasi and bushbuck Tragelaphus scriptus. Persistent infection with BVD virus was found in 1 of 303 antibody-free eland but not in the smaller sample of 102 antibody-free buffalo Syncerus caffer. Antib…

High seroconversion rate to Rift Valley fever virus in cattle and goats in far northern KwaZulu-Natal, South Africa, in the absence of reported outbreaks.

BACKGROUND: Rift Valley fever (RVF) is a mosquito-borne zoonotic disease characterized in South Africa by large epidemics amongst ruminant livestock at very long, irregular intervals, mainly in the central interior. However, the presence and patterns of occurrence of the virus in the eastern parts of the country are poorly known. This study aimed to detect the presence of RVF virus (RVFV) in cattle and goats in far northern KwaZulu-Natal province and to estimate the prevalence of antibodies to the virus and the incidence rate of seroconversion. METHODOLOGY: Cross-sectional studies were perfor…

Rift valley Fever virus encephalitis is associated with an ineffective systemic immune response and activated T cell infiltration into the CNS in an immunocompetent mouse model.

BACKGROUND: Rift Valley fever virus (RVFV) causes outbreaks of severe disease in livestock and humans throughout Africa and the Arabian Peninsula. In people, RVFV generally causes a self-limiting febrile illness but in a subset of individuals, it progresses to more serious disease. One manifestation is a delayed-onset encephalitis that can be fatal or leave the afflicted with long-term neurologic sequelae. In order to design targeted interventions, the basic pathogenesis of RVFV encephalitis must be better understood. METHODOLOGY/PRINCIPAL FINDINGS: To characterize the host immune responses a…

Detection of Puumala and Rift Valley Fever virus by quantitative RT-PCR and virus viability tests in samples of blood dried and stored on filter paper.

Haemorrhagic fever viruses cause emerging infections worldwide, and blood or serum is the main sample used for diagnosis. However, storage and transportation of such samples from remote areas to regional laboratories may be complicated and expensive. In this study, a novel approach was evaluated for the detection of Puumala hantavirus (PUUV) RNA and Rift Valley fever virus (RVFV) RNA. Whole-blood samples spiked with viable virus particles were tested in parallel with clinical samples from patients with acute haemorrhagic fever with renal syndrome (nephropathia epidemica). Individual blood samp…

The Rift Valley fever virus nonstructural protein NSs is phosphorylated at serine residues located in casein kinase II consensus motifs in the carboxy-terminus.

The S segment of Rift Valley fever virus (Bunyaviridae, Phlebovirus) codes for two proteins, the nucleoprotein N and the nonstructural protein NSs. The NSs protein is a phosphoprotein of unknown function that is localized in the cytoplasm and the nuclei of infected cells where it forms filamentous structures. To characterize further the protein expressed in VC10 cells infected with the MP12 strain, we analyzed its phosphorylation states and showed that phosphorylated forms were found in both compartments. Cytoplasmic and nuclear NSs were phosphorylated only at serine residues. Phosphopeptide m…

Assessment of an rDNA probe filter hybridization assay for the detection of Rift Valley fever virus RNA in human serum samples from the Mauritanian epidemic.

The Rift Valley fever virus (RVFV) epidemic that occurred in southern Mauritania during the 1987 rainy season provided a unique opportunity to test and evaluate a recently developed, M-segment-specific, nucleic acid filter hybridization assay on a large collection of infected human serum samples. It afforded the opportunity to compare the procedure with two other methods for detecting virus: virus isolation and antigen detection by ELISA. The filter hybridization procedure employed a polyethylene-glycol-precipitation and proteinase-K-digestion sample treatment step developed specifically for p…

Exploring potential risk pathways with high risk groups for urban Rift Valley fever virus introduction, transmission, and persistence in two urban centers of Kenya.

Rift Valley fever virus (RVFV) is a zoonotic arbovirus that has profound impact on domestic ruminants and can also be transmitted to humans via infected animal secretions. Urban areas in endemic regions across Africa have susceptible animal and human hosts, dense vector distributions, and source livestock (often from high risk locations to meet the demand for animal protein). Yet, there has never been a documented urban outbreak of RVF. To understand the likely risk of RVFV introduction to urban communities from their perspective and guide future initiatives, we conducted focus group discussio…