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Viral hemorrhagic fever antibodies in Nigerian populations.

Using the immunofluorescence test, a serosurvey for antibodies to five viral agents associated with hemorrhagic febrile infections was conducted with 1,677 human sera from different parts of Nigeria. Three hundred fifty-seven (21.3%) were positive for Lassa virus antibody, while antibodies to Rift Valley fever virus were detected in 42 (2.5%) of the sera. Testing for Rift Valley fever virus antibody was confirmed by plaque reduction neutralization test. Antibodies to Ebola and Marburg viruses were detected in 30 and 29 sera, respectively. Of the 357 Lassa virus antibody-positive sera, 297 (83.…

Closing the Rift: Discovery of a novel virus receptor.

In this issue of Cell, Ganaie et al. reports the identification of LRP1 as a receptor of the highly pathogenic Rift Valley fever virus. By using genome-wide CRISPR-Cas9 screening and functional studies, Ganaie et al. identified LRP1 and several co-factors as essential elements for virus infection.

Seroprevalence of alphavirus antibodies in a cross-sectional study in southwestern Tanzania suggests endemic circulation of chikungunya.

BACKGROUND: To date, Alphavirus infections and their most prominent member, chikungunya fever, a viral disease which first became apparent i … iated with participant age, low to intermediate elevation, flat terrain and with IgG positivity for Rift Valley fever, Flaviviridae, and rickettsiae of the spotted fever group. When comparing the geographical distribution of Alphavirus seropositivity to that of Rift Valley fever, it was obvious that Alphaviruses had spread more widely throughout the study area, whi …

Vector Competence Assays for RVFV in Mosquitoes.

Rift Valley fever virus (RVFV) is the causative agent of Rift Valley fever, a mosquito-borne zoonotic febrile illness that primarily affects ruminants, camels, and humans. It is endemic in sub-Saharan Africa and the Arabian Peninsula, albeit with the potential to spread to and establish in non-endemic countries where mosquito vectors are present. Assessing the vector competence (VC) of local mosquito populations is essential for risk evaluation and to develop more accurate control and surveillance strategies. Herein, parameters for VC experimental design, as well as protocols for mosquito rear…

Pseudotyped Viruses for Phlebovirus.

Rift Valley fever virus (RVFV) is a member of the Phlebovirus genus, one of the 20 genera in the Phenuiviridae family. RVFV causes disease in animals and humans and is transmitted by sandflies or ticks. However, research into RVFV is limited by the requirement for biosafety level 3 (BSL-3) containment. Pseudotyped virus overcomes this limitation as it can be handled in a BSL-2 environment. Pseudotyped RVFV possesses an identical envelope protein structure to that of the authentic virus, simulating the same process of receptor binding and membrane fusion to host cells. Pseudotyped phleboviruses…

Using RVFV as a Vector Platform for the Expression of Ruminant Disease Antigens.

Live attenuated viruses remain as vaccine agents with unparalleled performance in terms of duration, magnitude, and breadth of induced immune responses. As the yellow fever-attenuated vaccine strain Y17D, attenuated Rift Valley fever virus shares features suitable to be used as a viral vector for heterologous antigen expression and bivalent vaccine development. Current reverse genetics technology showed the successful rescue of RVFV carrying foreign antigens with little immunogenicity loss in experimental animal models. We show here the basic experimental protocol to achieve the expression of …

The potential role of Rattus rattus in enzootic cycle of Rift Valley Fever in Egypt. 1-Detection of RVF antibodies in R. rattus blood samples by both enzyme linked immuno sorbent assay (ELISA) and immuno-diffusion technique (ID).

Three hundreds of Rattus rattus (R. rattus) were trapped from 3 different governorates of Egypt (one hundred each), blood samples were withdrawal and subjected for detection of anti-RVF antibodies by both ELISA and ID techniques. The prevalence rate of antibodies by ELISA were 88 (29.33%) positive out of 300 tested blood samples, the highest rate was in Behira governorate 36 (36%) and the lowest one was in Alexandria governorate 22 (22%) while it was 30 (30%) in Minia governorate. But when ID technique was applied, it gave only 18 (6%) positive samples out of 300 tested blood samples with the

Preliminary Evaluation of a Bunyavirus Vector for Cancer Immunotherapy.

Replicon particles of Rift Valley fever virus, referred to as nonspreading Rift Valley fever virus (NSR), are intrinsically safe and highly immunogenic. Here, we demonstrate that NSR-infected human dendritic cells can activate CD8(+) T cells in vitro and that prophylactic and therapeutic vaccinations of mice with NSR encoding a tumor-associated CD8 peptide can control the outgrowth of lymphoma cells in vivo. These results suggest that the NSR system holds promise for cancer immunotherapy.

Large herbivore loss has complex effects on mosquito ecology and vector-borne disease risk.

Loss of biodiversity can affect transmission of infectious diseases in at least two ways: by altering host and vector abundance or by influencing host and vector behaviour. We used a large herbivore exclusion experiment to investigate the effects of wildlife loss on the abundance and feeding behaviour of mosquito vectors and to explore consequences for vector-borne disease transmission. Large herbivore loss affected both mosquito abundance and blood-feeding behaviour. For Aedes mcintoshi, the dominant mosquito species in our study and a primary vector of Rift Valley fever virus (RVFV), abundan…

Complement fixing antibodies against arboviruses in horses at Lagos, Nigeria.

Sixty-two sera horse collected from two stables at Lagos, Nigeria, were tested for complement fixing antibody to 8 arbovirus antigens; Chikungunya, Igbo-Ora, Yellow fever, Wesselsbron, West Nile, Potiskum, Uganda S and Rift Valley fever. Ten per cent of the horse sera examined contained CF antibody to one or more of the test antigens and indicated considerable arbovirus activity in the two stables. Reactions with flavivirus antigens were most common and the highest antibody titres were obtained with Wesselsbron and Yellow fever viruses. Eleven per cent of the sera tested reacted with alphaviru…

Palmitoylation of cysteine 69 from the COOH-terminal of band 3 protein in the human erythrocyte membrane. Acylation occurs in the middle of the consensus sequence of F--I-IICLAVL found in band 3 protein and G2 protein of Rift Valley fever virus.

One of the major physiologic functions of erythrocytes is the mediation of chloride-bicarbonate exchange in the transport of carbon dioxide … n site was Phe-Thr-Gly-Ile-Gln-Ile-Ile-Cys-Leu-Ala-Val-Leu, which is conserved in the G2 protein of Rift Valley fever virus as Phe-Ser-Ser-Ile-Ala-Ile-Ile-Cys-Leu-Ala-Val-Leu. The G2 protein, like Band 3, is a polytopic transmembrane protein. Although acylation of the cysteine residue of G2 protein has not been examined, the Phe-X-X-Ile-X-Ile-Ile-Cys-Leu-Ala-Val-Le …

The AFHSC-Division of GEIS Operations Predictive Surveillance Program: a multidisciplinary approach for the early detection and response to disease outbreaks.

The Armed Forces Health Surveillance Center, Division of Global Emerging Infections Surveillance and Response System Operations (AFHSC-GEIS) … This multidisciplinary program is rooted in over 10 years experience in predictive surveillance for Rift Valley fever outbreaks in Eastern Africa. The AFHSC-GEIS Rift Valley fever project is based on the identification and use of disease-emergence critical detection points as reliable signals for increased outbreak risk. The AFHSC-GEIS predictive surveillance progr …

A single immunization with MVA expressing GnGc glycoproteins promotes epitope-specific CD8+-T cell activation and protects immune-competent mice against a lethal RVFV infection.

BACKGROUND: Rift Valley fever virus (RVFV) is a mosquito-borne pathogen causing an important disease in ruminants often transmitted to humans after epizootic outbreaks in African and Arabian countries. To help combat the spread of the disease, prophylactic measures need to be developed and/or improved. METHODOLOGY/PRINCIPAL FINDINGS: In this work, we evaluated the immunogenicity and protective efficacy of recombinant plasmid DNA and modified vaccinia virus Ankara (rMVA) vectored vaccines against Rift Valley fever in mice. These recombinant vaccines encoded either of two components of the Rift…

Incomplete bunyavirus particles can cooperatively support virus infection and spread.

Bunyaviruses lack a specific mechanism to ensure the incorporation of a complete set of genome segments into each virion, explaining the generation of incomplete virus particles lacking one or more genome segments. Such incomplete virus particles, which may represent the majority of particles produced, are generally considered to interfere with virus infection and spread. Using the three-segmented arthropod-borne Rift Valley fever virus as a model bunyavirus, we here show that two distinct incomplete virus particle populations unable to spread autonomously are able to efficiently complement ea…

Уровни серопозитивности зоонотических патогенов в небольших сгустках и связанные с этим риски для здоровья населения на неофициальных городских рынках Замбии.

Неформальные рынки скота являются важным источником белков животного происхождения для растущего городского населения в таких странах, как Замбия. Параллельно они могут также представлять собой пути зоонотической передачи патогена людям. Этот риск усугубляется ограниченным мониторингом заболеваний и плохими системами контроля в отношении биозащищенности и общественного здравоохранения. Цель этого исследования состояла в том, чтобы изучить риски распространения зоонотических заболеваний на двух крупнейших в Замбии неформальных небольших рынках червей, расположенных в Лусаке и Касумбалесе, путем

Совпадение в аннотации оригинала
Informal livestock markets are an important source of animal-derived proteins for growing urban populations in countries such as Zambia. In … ed and analysed for antibodies for the zoonotic pathogens Brucella spp., Coxiella (C.) burnetii and Rift Valley fever virus (RVFV), using commercially available enzyme linked immunosorbent assays (ELISA). In addition, slaughterhouse activities were observed and semi-structured interviews and focus group discussions held with slaughterhouse workers and small ruminan …

Antibodies against haemorrhagic fever viruses in Kenya populations.

Human sera from Lodwar (77 sera), Nzoia (841 sera), Masinga (251 sera), Laisamis (174 sera) and the Malindi/Kilifi area (556 sera) in Kenya were tested by indirect immunofluorescence for antibodies against Marburg, Ebola (Zaire and Sudan strains), Congo haemorrhagic fever, Rift Valley fever and Lassa viruses. Antibodies against Ebola virus, particularly the Zaire strain, were detected in all regions and were, over-all, more abundant than antibodies against the other antigens. Ebola and Marburg antibody prevalence rates were highest in the samples from Lodwar and Laisamis, both semi-desert area…