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A Species-Independent Lateral Flow Test to Detect Rift Valley Fever Virus Antibodies Using a Double Antigen Approach.

Rift Valley fever virus (RVFV) is a re-emerging, vector-borne pathogen endemic to Africa and the Arabian Peninsula, posing an increasing threat to human and animal health. Outbreaks have severe economic and social impacts on farmers, communities, and governments. Current diagnostic methods rely on PCR and ELISA; however, rapid pen-side tests would enable faster, cost-effective monitoring and outbreak control. Here, a species- and immunoglobulin class-independent capillary flow immunodiagnostic assay (lateral flow test; LFT) for detecting RVFV-specific antibodies is described. The assay uses a …

Pathogenicity of Rift Valley fever virus: Organ-specific clinical outcomes and hidden drivers of virulence - a narrative review.

Rift Valley fever virus (RVFV) is a mosquito-borne phlebovirus posing major threats to human and animal health. Despite decades of research, the determinants governing diverse clinical manifestations remain incompletely understood. This narrative review examines four central facets: i) exposure route impacts on disease outcome; ii) field strain diversity and organ-specific virulence; iii) genome reassortment driving viral evolution; and iv) organ-specific pathology including the overlooked placental/retinal infections. Differences among infection routes, viral strains, and host species complic…

Early outbreak detection in endemic settings using a novel method applied to sparse Rift Valley fever incidence data.

Rift Valley Fever (RVF) is a mosquito-borne zoonotic disease often linked to climatic factors. However, identifying the onset and duration of outbreaks can be hindered by high numbers of zero counts in sparse surveillance data. We analyzed monthly RVF data from Kenya (2015-2022), compared the performance of widely used outbreak-detection methods, and developed Negative Binomial models augmented with a hidden Markov process and zero-inflation to address data sparsity. Our proposed framework estimates monthly probabilities of transitioning between endemic and epidemic phases, improving outbreak …

Evolutionary dynamics and molecular adaptation of Rift Valley fever virus across human and non-human outbreaks in Africa.

BACKGROUND: Rift Valley fever virus (RVFV) is an emerging zoonotic virus of major public health and veterinary concern across Africa. Although past genomic studies have focused on outbreak response and lineage classification, the molecular mechanisms driving viral persistence and adaptation remain poorly understood. This study aimed to identify RVFV protein-coding mutations and adaptive signatures across multiple epidemics and epizootics in Africa. METHODS: This retrospective genomic analysis examined 596 RVFV segment sequences retrieved from the NCBI Virus database, including L (n = 173), M …

"Without a man's decision, nothing works": Building resilience to Rift Valley fever in pastoralist communities in Isiolo Kenya.

Rift Valley Fever (RVF) is a zoonotic disease that affects both livestock and humans. Men and women in pastoralist communities are vulnerable to RVF risk exposure because of their different roles and reliance on livestock products. This study sought to understand how ownership and decision-making in pastoralist male and female-headed households influence coping mechanisms and resilience to Rift Valley fever (RVF), using the three resilience capacities of absorptive, adaptive, and transformative. This study was conducted in two sub-counties (Garbatulla) and Merti), Isiolo County, Kenya. Data we…

Rift Valley fever seroprevalence and risk factors among human populations in Uganda's cattle corridor: a cross-sectional study.

INTRODUCTION: Rift Valley fever (RVF) is an epidemic-prone zoonotic disease whose distribution of exposure is poorly described in endemic communities. We investigated the seroprevalence and risk factors for RVF among humans in Uganda's cattle corridor. METHODS: This cross-sectional study used data and stored plasma specimens collected by the Uganda population-based HIV impact assessment (UPHIA) survey 2016/2017. Participants were sampled from 35 districts of the cattle corridor. Ethical and regulatory approvals were obtained to use the UPHIA data and to test the specimens for the presence of …

Modeling sparse Rift Valley fever incidence data: a Bayesian perspective on zero-inflated self-exciting and autoregressive models.

BACKGROUND: Rift Valley fever (RVF) is a mosquito-borne zoonotic disease for which predictive modeling is often hindered by sparse data, particularly the high frequency of zero counts in both human and livestock surveillance systems. While zero-inflated models are commonly used for sparse data, several temporal count modelling frameworks exist, including less common self-exciting models that assume an initial case increases the likelihood of subsequent cases. METHODS: This study compares three zero-inflated Bayesian models: the negative binomial (ZINB) with autoregressive temporal random effe…

Correction: Understanding knowledge, attitude and perception of Rift Valley fever in Baringo South, Kenya: A cross-sectional study.

[This corrects the article DOI: 10.1371/journal.pgph.0002195.].

Genome characterization of Rift Valley fever virus isolated from cattle, goats and sheep during interepidemic periods in Kenya.

Rift Valley fever virus (RVFV) is a mosquito-borne RNA virus of the Phlebovirus genus in the phenuviridae family. Its genome is trisegmented with small (S), medium (M) and large (L) fragments. In nature, the virus exists as a single serotype that is responsible for outbreaks of Rift Valley fever (RVF), a zoonotic disease that often occurs in Africa and the Middle East. RVFV genomes are thought to undergo both recombination and reassortment and investigations of these events is important for monitoring the emergence of virulent strains and understanding the evolutionary characteristics of this …

Have you heard of Rift Valley fever? Findings from a multi-country study in East and Central Africa.

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. MATERIALS AND METHODS: Individuals aged ≥10 years with acute febrile illness were enrolled from six health facilities in Kenya, Uganda, and the Democratic Republic of Congo (DRC). Sociodemographic information was collected and participants asked questions on RVF …

Serological Evidence of Cryptic Rift Valley Fever Virus Transmission Among Humans and Livestock in Central Highlands of Kenya.

Although the highlands of East Africa lack the geo-ecological landmarks of Rift Valley fever (RVF) disease hotspots to participate in cyclic RVF epidemics, they have recently reported growing numbers of small RVF clusters. Here, we investigated whether RVF cycling occurred among livestock and humans in the central highlands of Kenya during inter-epidemic periods. A 2-year prospective hospital-based study among febrile patients (March 2022-February 2024) in Murang'a County of Kenya was followed by a cross-sectional human-animal survey. A total of 1468 febrile patients were enrolled at two clini…

Mapping the risk of Rift Valley fever in Uganda using national seroprevalence data from cattle, sheep and goats.

Uganda has had repeated outbreaks of Rift Valley fever (RVF) since March 2016 when human and livestock cases were reported in Kabale after a long interval. The disease has a complex and poorly described transmission patterns which involves several mosquito vectors and mammalian hosts (including humans). We conducted a national serosurvey in livestock to determine RVF virus (RVFV) seroprevalence, risk factors, and to develop a risk map that could be used to guide risk-based surveillance and control measures. A total of 3,253 animals from 175 herds were sampled. Serum samples collected were scre…

У мавританских животных и людей устойчиво распространяется вирусная зоонотическая болезнь лихорадки долины Рифт: обзор повествования.

Согласно сообщениям, в Мавритании в 1987, 2010, 2012, 2015 и 2020 годах постоянно распространяется вирус лихорадки Рифт долины (RVF). Мавритания, как представляется, отдается предпочтение вирусу RVF из-за его постоянной вспышки. В последнее время в девяти мавританских вилайях было подтверждено, что в период с 30 августа по 17 октября 2022 года было зарегистрировано 47 случаев гибели людей (23 человека с 49 процентами КФР). В большинстве случаев речь шла о скотоводах, занимающихся животноводством. Целью обзора было понимание происхождения, причин и мер по борьбе с этим вирусом.МЕТОДЫ: Были проа

Совпадение в аннотации оригинала
BACKGROUND AND AIM: Rift valley fever (RVF) virus (RVFV) is reportedly steadily circulating in Mauritania being repeated in 1987, 2010, 2012, 2015, and 2020. Mauritania seems a preferred niche for RVF virus due to its persistent outbreak there. Lately, nine Mauritanian wilayas confirmed 47 (23 fatalities with 49% CFR) human cases between August 30 and Octobe…

A highly potent human neutralizing antibody prevents vertical transmission of Rift Valley fever virus in a rat model.

Rift Valley fever virus (RVFV) is an emerging mosquito-transmitted virus that circulates in livestock and humans in Africa and the Middle East. Outbreaks lead to high rates of miscarriages in domesticated livestock. Women are also at risk of vertical virus transmission and late-term miscarriages. MAb RVFV-268 is a highly potent recombinant neutralizing human monoclonal antibody that targets RVFV. Here we show that mAb RVFV-268 reduces viral replication in rat placenta explant cultures and prevents vertical transmission in a rat model of congenital RVF. Passive transfer of mAb RVFV-268 from mot…

Discovery of Rift Valley fever virus natural pan-inhibitors by targeting its multiple key proteins through computational approaches.

The Rift Valley fever virus (RVFV) is a zoonotic arbovirus and pathogenic to both humans and animals. Currently, no proven effective RVFV drugs or licensed vaccine are available for human or animal use. Hence, there is an urgent need to develop effective treatment options to control this viral infection. RVFV glycoprotein N (GN), glycoprotein C (GC), and nucleocapsid (N) proteins are attractive antiviral drug targets due to their critical roles in RVFV replication. In present study, an integrated docking-based virtual screening of more than 6000 phytochemicals with known antiviral activities a…

Intranasal Exposure to Rift Valley Fever Virus Live-Attenuated Strains Leads to High Mortality Rate in Immunocompetent Mice.

Rift Valley fever virus (RVFV) is a pathogenic arthropod-borne virus that can cause serious illness in both ruminants and humans. The virus can be transmitted by an arthropod bite or contact with contaminated fluids or tissues. Two live-attenuated veterinary vaccines-the Smithburn (SB) and Clone 13 (Cl.13)-are currently used during epizootic events in Africa. However, their residual pathogenicity (i.e., SB) or potential of reversion (i.e., Cl.13) causes important adverse effects, strongly limiting their use in the field. In this study, we infected immunocompetent mice with SB or Cl.13 by a sub…

Single-dose of a replication-competent adenovirus-vectored vaccine provides sterilizing protection against Rift Valley fever virus challenge.

Rift Valley fever virus (RVFV) is one of the most important virulent pathogens causing severe disease in animals and humans. However, there is currently no approved vaccine to prevent RVFV infection in humans. The use of human adenovirus serotype 4 (Ad4) as a vector for an RVFV vaccine has not been reported. Here, we report the generation of a replication-competent recombinant Ad4 vector expressing codon-optimized forms of the RVFV glycoproteins Gn and Gc (named Ad4-GnGc). Intramuscular immunization with Ad4-GnGc elicited robust neutralizing antibodies against RVFV and cellular immune response…

Comparative thermo-stability of two Rift Valley fever virus vaccine candidate CL13T with a recombinant arMP-12ΔNSm21/384.

Rift Valley fever (RVF) is a zoonotic, viral disease, transmitted by mosquitoes, characterized by high mortality rates in young animals. RVF is an endemic and enzootic disease in the Arabian Peninsula and Africa, causing public health and economic instability. Therefore, it is important to develop vaccines to minimize outbreaks and combat the disease. We documented the stability of the thermo-stability of live attenuated RVF CL13T and recombinant arMP-12ΔNSm21/384 vaccine candidates at different temperatures, including these vaccine viruses in liquid and lyophilized form. The study revealed th…

Comparison of Two Rift Valley Fever Serological Tests in Cameroonian Cattle Populations Using a Bayesian Latent Class Approach.

Rift Valley Fever is an important zoonotic viral disease of livestock occurring across much of Africa causing acute febrile illness, abortion, and neonatal death in livestock particularly sheep and cattle and a range of disease in humans from mild flu-like symptoms to more severe haemorrhagic fever and death. Understanding the epidemiology requires well-evaluated tools including antibody detection ELISAs. It is well-recognized that tests developed in one population do not necessarily perform as well when used in different populations and it is therefore important to assess tests in the populat…

Using species distribution models to predict potential hot-spots for Rift Valley Fever establishment in the United Kingdom.

Vector borne diseases are a continuing global threat to both human and animal health. The ability of vectors such as mosquitos to cover larg … to estimate the habitat suitability for presence of mosquito species in the UK deemed competent for Rift Valley fever virus (RVF) and demonstrate its application in an assessment of the relative risk of establishment of RVF virus in the UK livestock population. The consensus model utilises observed UK mosquito surveillance data, along with climatic and geographic p …