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McMillen CM, Megli C, Radisic R, Skvarca LB, Hoehl RM, Boyles DA, McGaughey JJ, Bird BH, McElroy AK, Hartman AL. Vaccine strains of Rift Valley fever virus exhibit attenuation at the maternal-fetal placental interface. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.31.596800. [PMID: 38854055 PMCID: PMC11160702 DOI: 10.1101/2024.05.31.596800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Rift Valley fever virus (RVFV) infection causes abortions in ruminant livestock and is associated with an increased likelihood of miscarriages in women. Using sheep and human placenta explant cultures, we sought to identify tissues at the maternal-fetal interface targeted by RVFV. Sheep villi and fetal membranes were highly permissive to RVFV infection resulting in markedly higher virus titers than human cultures. Sheep cultures were most permissive to wild-type RVFV and ΔNSm infection, while live attenuated RVFV vaccines (LAVs; MP-12, ΔNSs, and ΔNSs/ΔNSm) exhibited reduced replication. The human fetal membrane restricted wild-type and LAV replication, and when infection occurred, it was prominent in the maternal-facing side. Type-I and type-III interferons were induced in human villi exposed to LAVs lacking the NSs protein. This study supports the use of sheep and human placenta explants to understand vertical transmission of RVFV in mammals and whether LAVs are attenuated at the maternal-fetal interface.
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Affiliation(s)
- Cynthia M. McMillen
- University of Pittsburgh, Center for Vaccine Research, Pittsburgh, PA, USA
- University of Pittsburgh, Department of Infectious Diseases and Microbiology, School of Public Health, Pittsburgh, PA, USA
| | - Christina Megli
- University of Pittsburgh School of Medicine and the Magee-Womens Research Institute, Division of Maternal-Fetal Medicine, Division of Reproductive Infectious Disease, Department of Obstetrics, Gynecology and Reproductive Sciences, Pittsburgh, PA, USA
| | - Rebecca Radisic
- One Health Institute, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - Lauren B. Skvarca
- University of Pittsburgh School of Medicine, Department of Pathology, Pittsburgh, PA, USA
| | - Ryan M. Hoehl
- University of Pittsburgh, Center for Vaccine Research, Pittsburgh, PA, USA
| | - Devin A. Boyles
- University of Pittsburgh, Center for Vaccine Research, Pittsburgh, PA, USA
| | | | - Brian H. Bird
- One Health Institute, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - Anita K. McElroy
- University of Pittsburgh, Center for Vaccine Research, Pittsburgh, PA, USA
- University of Pittsburgh School of Medicine, Department of Pediatrics, Division of Pediatric Infectious Disease, Pittsburgh, PA, USA
| | - Amy L. Hartman
- University of Pittsburgh, Center for Vaccine Research, Pittsburgh, PA, USA
- University of Pittsburgh, Department of Infectious Diseases and Microbiology, School of Public Health, Pittsburgh, PA, USA
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Hcini N, Lambert V, Picone O, Carod JF, Carles G, Pomar L, Epelboin L, Nacher M. Arboviruses and pregnancy: are the threats visible or hidden? Trop Dis Travel Med Vaccines 2024; 10:4. [PMID: 38355934 PMCID: PMC10868105 DOI: 10.1186/s40794-023-00213-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 11/22/2023] [Indexed: 02/16/2024] Open
Abstract
Mosquito-borne arboviral diseases are a global concern and can have severe consequences on maternal, neonatal, and child health. Their impact on pregnancy tends to be neglected in developing countries. Despite hundreds of millions of infections, 90% pregnancies being exposed, scientific data on pregnant women is poor and sometimes non-existent. Recently and since the 2016 Zika virus outbreak, there has been a newfound interest in these diseases. Through various neuropathogenic, visceral, placental, and teratogenic mechanisms, these arbovirus infections can lead to fetal losses, obstetrical complications, and a wide range of congenital abnormalities, resulting in long-term neurological and sensory impairments. Climate change, growing urbanization, worldwide interconnectivity, and ease of mobility allow arboviruses to spread to other territories and impact populations that had never been in contact with these emerging agents before. Pregnant travelers are also at risk of infection with potential subsequent complications. Beyond that, these pathologies show the inequalities of access to care on a global scale in a context of demographic growth and increasing urbanization. It is essential to promote research, diagnostic tools, treatments, and vaccine development to address this emerging threat.Background The vulnerability of pregnant women and fetuses to emergent and re-emergent pathogens has been notably illustrated by the outbreaks of Zika virus. Our comprehension of the complete scope and consequences of these infections during pregnancy remains limited, particularly among those involved in perinatal healthcare, such as obstetricians and midwives. This review aims to provide the latest information and recommendations regarding the various risks, management, and prevention for pregnant women exposed to arboviral infections.
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Affiliation(s)
- Najeh Hcini
- Department of Obstetrics and Gynecology, West French Guiana Hospital Center, Saint-Laurent-du-Maroni, French Guiana.
- CIC Inserm 1424 and DFR Santé Université Guyane, Cayenne, French Guiana, France.
| | - Véronique Lambert
- Department of Obstetrics and Gynecology, West French Guiana Hospital Center, Saint-Laurent-du-Maroni, French Guiana
| | - Olivier Picone
- Department of Obstetrics and Gynecology, Hôpital Louis Mourier, Hôpitaux Universitaires Paris Nord Val de Seine, Assistance Publique : Hôpitaux de Paris, Université Paris Diderot, CEDEX, Colombes, France
| | - Jean-Francois Carod
- Department of Biology, West French Guiana Hospital Center, Saint-Laurent-du-Maroni, French Guiana
| | - Gabriel Carles
- Department of Obstetrics and Gynecology, West French Guiana Hospital Center, Saint-Laurent-du-Maroni, French Guiana
| | - Léo Pomar
- Materno-Fetal and Obstetrics Research Unit, Department "Woman-Mother-Child", Lausanne University Hospital, Lausanne, Switzerland
| | - Loïc Epelboin
- Department of Infectious and Tropical Diseases, Cayenne General Hospital, Cayenne, French Guiana, France
| | - Mathieu Nacher
- Centre d'Investigation Clinique Antilles Guyane, Inserm CIC1424, Centre Hospitalier de Cayenne, 97300, Cayenne, French Guiana
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Bron GM, Wichgers Schreur PJ, de Jong MCM, van Keulen L, Vloet RPM, Koenraadt CJM, Kortekaas J, ten Bosch QA. Quantifying Rift Valley fever virus transmission efficiency in a lamb-mosquito-lamb model. Front Cell Infect Microbiol 2023; 13:1206089. [PMID: 38170150 PMCID: PMC10759236 DOI: 10.3389/fcimb.2023.1206089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 10/30/2023] [Indexed: 01/05/2024] Open
Abstract
Rift Valley fever virus (RVFV) is a (re)emerging mosquito-borne pathogen impacting human and animal health. How RVFV spreads through a population depends on population-level and individual-level interactions between vector, host and pathogen. Here, we estimated the probability for RVFV to transmit to naive animals by experimentally exposing lambs to a bite of an infectious mosquito, and assessed if and how RVFV infection subsequently developed in the exposed animal. Aedes aegypti mosquitoes, previously infected via feeding on a viremic lamb, were used to expose naive lambs to the virus. Aedes aegypti colony mosquitoes were used as they are easy to maintain and readily feed in captivity. Other mosquito spp. could be examined with similar methodology. Lambs were exposed to either 1-3 (low exposure) or 7-9 (high exposure) infectious mosquitoes. All lambs in the high exposure group became viremic and showed characteristic signs of Rift Valley fever within 2-4 days post exposure. In contrast, 3 out of 12 lambs in the low exposure group developed viremia and disease, with similar peak-levels of viremia as the high exposure group but with some heterogeneity in the onset of viremia. These results suggest that the likelihood for successful infection of a ruminant host is affected by the number of infectious mosquitoes biting, but also highlights that a single bite of an infectious mosquito can result in disease. The per bite mosquito-to-host transmission efficiency was estimated at 28% (95% confidence interval: 15 - 47%). We subsequently combined this transmission efficiency with estimates for life traits of Aedes aegypti or related mosquitoes into a Ross-McDonald mathematical model to illustrate scenarios under which major RVFV outbreaks could occur in naïve populations (i.e., R0 >1). The model revealed that relatively high vector-to-host ratios as well as mosquitoes feeding preferably on competent hosts are required for R0 to exceed 1. Altogether, this study highlights the importance of experiments that mimic natural exposure to RVFV. The experiments facilitate a better understanding of the natural progression of disease and a direct way to obtain epidemiological parameters for mathematical models.
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Affiliation(s)
- Gebbiena M. Bron
- Quantitative Veterinary Epidemiology, Wageningen University and Research, Wageningen, Netherlands
| | | | - Mart C. M. de Jong
- Quantitative Veterinary Epidemiology, Wageningen University and Research, Wageningen, Netherlands
| | - Lucien van Keulen
- Wageningen Bioveterinary Research, Wageningen University and Research, Lelystad, Netherlands
| | - Rianka P. M. Vloet
- Wageningen Bioveterinary Research, Wageningen University and Research, Lelystad, Netherlands
| | | | - Jeroen Kortekaas
- Wageningen Bioveterinary Research, Wageningen University and Research, Lelystad, Netherlands
| | - Quirine A. ten Bosch
- Quantitative Veterinary Epidemiology, Wageningen University and Research, Wageningen, Netherlands
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Tinto B, Quellec J, Cêtre-Sossah C, Dicko A, Salinas S, Simonin Y. Rift Valley fever in West Africa: A zoonotic disease with multiple socio-economic consequences. One Health 2023; 17:100583. [PMID: 37664171 PMCID: PMC10474305 DOI: 10.1016/j.onehlt.2023.100583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 06/12/2023] [Accepted: 06/12/2023] [Indexed: 09/05/2023] Open
Abstract
Rift Valley fever virus (RVFV) is an arbovirus that causes Rift Valley fever (RVF), a zoonotic disease that mainly affects domestic and wildlife ruminants and humans. The first epidemic in North-Western and West Africa occurred in Senegal and Mauritania in 1987, two countries where RVF is now endemic. Slaughterhouse workers, farmers, herders and veterinarians are at high risk of exposure to RVF. Beyond the health threat, RVF is considered to cause major socio-economic problems, specifically in developing countries where livestock farming and trade are important economic activities. Indeed, the mortality rate linked to RVF infection can reach 95-100% in newborns and young animals. In West Africa, livestock production is a key factor for food production and for national economics. Epizootics caused by RVF can therefore have serious socio-economic consequences by impacting multisectoral economics, the psycho-social health of pastoral communities, and food security. Improving prevention strategies against RVF, including vaccination, enhancing knowledge of RVF and correcting any inappropriate behaviors by populations of endemics areas, as well as better monitoring of RVF ecological factors are effective ways to better foresee and control outbreaks of RVF and its socio-economical side-effects in countries at high risk of occurrence of the disease.
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Affiliation(s)
- Bachirou Tinto
- Pathogenesis and Control of Chronic and Emerging Infections, University of Montpellier, INSERM, Etablissement Français du Sang, Montpellier, France
- Laboratoire National de Référence des Fièvres Hémorragiques Virale, Centre MURAZ, Institut National de Santé Publique (INSP), Bobo-Dioulasso, Burkina Faso
| | - Jordan Quellec
- Pathogenesis and Control of Chronic and Emerging Infections, University of Montpellier, INSERM, Etablissement Français du Sang, Montpellier, France
- ASTRE, University of Montpellier, CIRAD, INRAe, Montpellier, France
| | | | - Amadou Dicko
- Laboratoire central de référence, Institut National de Santé Publique (INSP), Ouagadougou, Burkina Faso
- Ministère de l'Agriculture, des ressources animales et halieutiques du Burkina Faso, Ouagadougou, Burkina Faso
| | - Sara Salinas
- Pathogenesis and Control of Chronic and Emerging Infections, University of Montpellier, INSERM, Etablissement Français du Sang, Montpellier, France
| | - Yannick Simonin
- Pathogenesis and Control of Chronic and Emerging Infections, University of Montpellier, INSERM, Etablissement Français du Sang, Montpellier, France
- ASTRE, University of Montpellier, CIRAD, INRAe, Montpellier, France
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5
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Smith CB, Hodges NF, Kading RC, Campbell CL. Dishevelled Has Anti-Viral Activity in Rift Valley Fever Virus Infected Aedes aegypti. Viruses 2023; 15:2140. [PMID: 38005818 PMCID: PMC10675198 DOI: 10.3390/v15112140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 10/17/2023] [Accepted: 10/19/2023] [Indexed: 11/26/2023] Open
Abstract
Mosquitoes in the genera Aedes and Culex are vectors of Rift Valley fever virus (RVFV), which emerges in periodic epidemics in Africa and Saudi Arabia. Factors that influence the transmission dynamics of RVFV are not well characterized. To address this, we interrogated mosquito host-signaling responses through analysis of differentially expressed genes (DEGs) in two mosquito species with marked differences in RVFV vector competence: Aedes aegypti (Aae, low competence) and Culex tarsalis (Cxt, high competence). Mosquito-host transcripts related to three different signaling pathways were investigated. Selected genes from the Wingless (Wg, WNT-beta-catenin) pathway, which is a conserved regulator of cell proliferation and differentiation, were assessed. One of these, dishevelled (DSH), differentially regulates progression/inhibition of the WNT and JNK (c-Jun N-terminal Kinase) pathways. A negative regulator of the JNK-signaling pathway, puckered, was also assessed. Lastly, Janus kinase/signal transducers and activators of transcription (JAK-STAT) are important for innate immunity; in this context, we tested domeless levels. Here, individual Aae and Cxt were exposed to RVFV MP-12 via oral bloodmeals and held for 14 days. Robust decreases in DEGs in both Aae and Cxt were observed. In particular, Aae DSH expression, but not Cxt DSH, was correlated to the presence/absence of viral RNA at 14 days post-challenge (dpc). Moreover, there was an inverse relationship between the viral copy number and aaeDSH expression. DSH silencing resulted in increased viral copy numbers compared to controls at 3 dpc, consistent with a role for aaeDSH in antiviral immunity. Analysis of cis-regulatory regions for the genes of interest revealed clues to upstream regulation of these pathways.
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Affiliation(s)
| | | | | | - Corey L. Campbell
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (C.B.S.); (R.C.K.)
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6
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Matsiela MS, Naicker L, Khoza T, Mokoena N. Safety and immunogenicity of inactivated Rift Valley Fever Smithburn viral vaccine in sheep. Virol J 2023; 20:221. [PMID: 37789354 PMCID: PMC10548704 DOI: 10.1186/s12985-023-02180-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 09/07/2023] [Indexed: 10/05/2023] Open
Abstract
BACKGROUND The live-attenuated Rift Valley Fever Smithburn (SB) vaccine is one of the oldest products widely used in ruminants for control of RVF infections. Vaccinations with RVF Smithburn result in residual pathogenic effect and is limited for use in non-pregnant animals. Commercially available RVFV inactivated vaccines are considered safer options to control the disease. These products are prepared from virulent RVFV isolates and present occupational safety concerns. This research study evaluates the ability of an inactivated SB vaccine strain to elicit neutralising antibody response in sheep. METHODS The RVF Smithburn vaccine was inactivated with binary ethylenimine at 37 °C. Inactivated RVFV cultures were adjuvanted with Montande™ Gel-01 and aluminium hydroxide (Al (OH)3) gel for immunogenicity and safety determination in sheep. The commercial RVF inactivated vaccine and a placebo were included as positive and negative control groups, respectively. RESULTS Inactivated RVFV vaccine formulations were safe with all animals showing no clinical signs of RVFV infection and temperature reactions following prime-boost injections. The aluminium hydroxide formulated vaccine induced an immune response as early as 14 days post primary vaccination with neutralising antibody titre of 1:20 and a peak antibody titre of 1:83 was reached on day 56. A similar trend was observed in the animal group vaccinated with the commercial inactivated RVF vaccine obtaining the highest antibody titre of 1:128 on day 56. The neutralizing antibody levels remained within a threshold for the duration of the study. Merino sheep vaccinated with Montanide™ Gel-01-Smithburn were characterised with overall lower immune response when compared to aluminium hydroxide vaccine emulsions. CONCLUSIONS These finding suggests that the inactivated RVF Smithburn vaccine strain adjuvanted with aluminium-hydroxide can be used an alternative to the products prepared from virulent RVFV isolates for protection of ruminants against the disease. The vaccine can further be evaluated for safety in pregnant ewes.
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Affiliation(s)
- Matome Selina Matsiela
- Onderstepoort Biological Products (Pty. Ltd), 100 Old Soutpan Road, Onderstepoort, Pretoria, 0110, South Africa
- Department of Biochemistry, School of Life Sciences, University of KwaZulu-Natal (Pietermaritzburg Campus), Scottsville, 3209, KwaZulu-Natal, South Africa
| | - Leeann Naicker
- Onderstepoort Biological Products (Pty. Ltd), 100 Old Soutpan Road, Onderstepoort, Pretoria, 0110, South Africa
| | - Thandeka Khoza
- Department of Biochemistry, School of Life Sciences, University of KwaZulu-Natal (Pietermaritzburg Campus), Scottsville, 3209, KwaZulu-Natal, South Africa.
| | - Nobalanda Mokoena
- Onderstepoort Biological Products (Pty. Ltd), 100 Old Soutpan Road, Onderstepoort, Pretoria, 0110, South Africa.
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Coler B, Cervantes O, Li M, Coler C, Li A, Shivakumar M, Every E, Schwartz D, Adams Waldorf KM. Common pathways targeted by viral hemorrhagic fever viruses to infect the placenta and increase the risk of stillbirth. Placenta 2023; 141:2-9. [PMID: 36939178 PMCID: PMC10102255 DOI: 10.1016/j.placenta.2022.10.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 09/19/2022] [Accepted: 10/02/2022] [Indexed: 01/06/2023]
Abstract
Viral hemorrhagic fevers (VHF) are endemic to Africa, South America and Asia and contribute to significant maternal and fetal morbidity and mortality. Viruses causing VHFs are typically zoonotic, spreading to humans through livestock, wildlife, or mosquito vectors. Some of the most lethal VHF viruses also impart a high-risk of stillbirth including ebolaviruses, Marburg virus (MARV), Lassa virus (LASV), and Rift Valley Fever Virus (RVFV). Large outbreaks and epidemics are common, though the impact on the mother, fetus and placenta is understudied from a public health, clinical and basic science perspective. Notably, these viruses utilize ubiquitous cellular surface entry receptors critical for normal placental function to enable viral invasion into multiple key cell types of the placenta and set the stage for maternal-fetal transmission and stillbirth. We employ insights from molecular virology and viral immunology to discuss how trophoblast expression of viral entry receptors for VHF viruses may increase the risk for viral transmission to the fetus and stillbirth. As the frequency of VHF outbreaks is expected to increase with worsening climate change, understanding the pathogenesis of VHF-related diseases in the placenta is paramount to predicting the impact of emerging viruses on the placenta and perinatal outcomes.
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Affiliation(s)
- Brahm Coler
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA, USA; Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, USA
| | - Orlando Cervantes
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA, USA; Department of Global Health, University of Washington, Seattle, WA, USA
| | - Miranda Li
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA, USA; Department of Biological Sciences, Columbia University, New York City, NY, USA
| | | | - Amanda Li
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA, USA; Case Western Reserve, Cleveland, OH, USA
| | - Megana Shivakumar
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA, USA
| | - Emma Every
- School of Medicine, University of Washington, Seattle, WA, USA
| | | | - Kristina M Adams Waldorf
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA, USA; Department of Global Health, University of Washington, Seattle, WA, USA.
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Nair N, Osterhaus ADME, Rimmelzwaan GF, Prajeeth CK. Rift Valley Fever Virus-Infection, Pathogenesis and Host Immune Responses. Pathogens 2023; 12:1174. [PMID: 37764982 PMCID: PMC10535968 DOI: 10.3390/pathogens12091174] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 09/09/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023] Open
Abstract
Rift Valley Fever Virus is a mosquito-borne phlebovirus causing febrile or haemorrhagic illness in ruminants and humans. The virus can prevent the induction of the antiviral interferon response through its NSs proteins. Mutations in the NSs gene may allow the induction of innate proinflammatory immune responses and lead to attenuation of the virus. Upon infection, virus-specific antibodies and T cells are induced that may afford protection against subsequent infections. Thus, all arms of the adaptive immune system contribute to prevention of disease progression. These findings will aid the design of vaccines using the currently available platforms. Vaccine candidates have shown promise in safety and efficacy trials in susceptible animal species and these may contribute to the control of RVFV infections and prevention of disease progression in humans and ruminants.
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Bermúdez-Méndez E, Angelino P, van Keulen L, van de Water S, Rockx B, Pijlman GP, Ciuffi A, Kortekaas J, Wichgers Schreur PJ. Transcriptomic Profiling Reveals Intense Host-Pathogen Dispute Compromising Homeostasis during Acute Rift Valley Fever Virus Infection. J Virol 2023; 97:e0041523. [PMID: 37306574 PMCID: PMC10308945 DOI: 10.1128/jvi.00415-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 05/13/2023] [Indexed: 06/13/2023] Open
Abstract
Rift Valley fever virus (RVFV) (family Phenuiviridae) can cause severe disease, and outbreaks of this mosquito-borne pathogen pose a significant threat to public and animal health. Yet many molecular aspects of RVFV pathogenesis remain incompletely understood. Natural RVFV infections are acute, characterized by a rapid onset of peak viremia during the first days post-infection, followed by a rapid decline. Although in vitro studies identified a major role of interferon (IFN) responses in counteracting the infection, a comprehensive overview of the specific host factors that play a role in RVFV pathogenesis in vivo is still lacking. Here, the host in vivo transcriptional profiles in the liver and spleen tissues of lambs exposed to RVFV are studied using RNA sequencing (RNA-seq) technology. We validate that IFN-mediated pathways are robustly activated in response to infection. We also link the observed hepatocellular necrosis with severely compromised organ function, which is reflected as a marked downregulation of multiple metabolic enzymes essential for homeostasis. Furthermore, we associate the elevated basal expression of LRP1 in the liver with RVFV tissue tropism. Collectively, the results of this study deepen the knowledge of the in vivo host response during RVFV infection and reveal new insights into the gene regulation networks underlying pathogenesis in a natural host. IMPORTANCE Rift Valley fever virus (RVFV) is a mosquito-transmitted pathogen capable of causing severe disease in animals and humans. Outbreaks of RVFV pose a significant threat to public health and can result in substantial economic losses. Little is known about the molecular basis of RVFV pathogenesis in vivo, particularly in its natural hosts. We employed RNA-seq technology to investigate genome-wide host responses in the liver and spleen of lambs during acute RVFV infection. We show that RVFV infection drastically decreases the expression of metabolic enzymes, which impairs normal liver function. Moreover, we highlight that basal expression levels of the host factor LRP1 may be a determinant of RVFV tissue tropism. This study links the typical pathological phenotype induced by RVFV infection with tissue-specific gene expression profiles, thereby improving our understanding of RVFV pathogenesis.
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Affiliation(s)
- Erick Bermúdez-Méndez
- Department of Virology and Molecular Biology, Wageningen Bioveterinary Research, Lelystad, The Netherlands
- Laboratory of Virology, Wageningen University & Research, Wageningen, The Netherlands
- Institute of Microbiology, Lausanne University Hospital, Lausanne, Switzerland
- Institute of Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Paolo Angelino
- Institute of Microbiology, Lausanne University Hospital, Lausanne, Switzerland
- Institute of Microbiology, University of Lausanne, Lausanne, Switzerland
- Bioinformatics Core Facility, Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Lucien van Keulen
- Department of Bacteriology, Host-Pathogen Interaction and Diagnostics Development, Wageningen Bioveterinary Research, Lelystad, The Netherlands
| | - Sandra van de Water
- Department of Virology and Molecular Biology, Wageningen Bioveterinary Research, Lelystad, The Netherlands
| | - Barry Rockx
- Department of Virology and Molecular Biology, Wageningen Bioveterinary Research, Lelystad, The Netherlands
| | - Gorben P. Pijlman
- Laboratory of Virology, Wageningen University & Research, Wageningen, The Netherlands
| | - Angela Ciuffi
- Institute of Microbiology, Lausanne University Hospital, Lausanne, Switzerland
- Institute of Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Jeroen Kortekaas
- Department of Virology and Molecular Biology, Wageningen Bioveterinary Research, Lelystad, The Netherlands
- Laboratory of Virology, Wageningen University & Research, Wageningen, The Netherlands
| | - Paul J. Wichgers Schreur
- Department of Virology and Molecular Biology, Wageningen Bioveterinary Research, Lelystad, The Netherlands
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10
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Comparison of RT-qPCR and RT-ddPCR with Rift valley fever virus (RVFV) RNA. Sci Rep 2023; 13:3085. [PMID: 36813787 PMCID: PMC9944419 DOI: 10.1038/s41598-023-29023-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 01/30/2023] [Indexed: 02/24/2023] Open
Abstract
Rift valley fever (RVF) is an important zoonotic disease caused by the Rift valley fever virus (RVFV) which can affect ruminants and humans. In this study, a comparison was done of the reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and reverse transcription-droplet digital PCR (RT-ddPCR) assays with synthesized RVFV RNA, cultured viral RNA, and mock clinical RVFV RNA samples. The genomic segments (L, M, and S) of three RVFV strains (BIME01, Kenya56, and ZH548) were synthesized and used as templates for in vitro transcription (IVT). Both the RT-qPCR and RT-ddPCR assays for RVFV did not react with any of the negative reference viral genomes. Thus, both the RT-qPCR and RT-ddPCR assays are specific to RVFV. The comparison of both the RT-qPCR and RT-ddPCR assays with serially diluted templates showed that the LoD of both assays are similar, and a concordant of the results was observed. The LoD of both assays reached the practical measurable minimum concentration. Taken altogether, the sensitivity of the RT-qPCR and RT-ddPCR assays is similar, and the material measured by RT-ddPCR can be used as a reference material for RT-qPCR.
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11
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Hao M, Bian T, Fu G, Chen Y, Fang T, Zhao C, Liu S, Yu C, Li J, Chen W. An adenovirus-vectored RVF vaccine confers complete protection against lethal RVFV challenge in A129 mice. Front Microbiol 2023; 14:1114226. [PMID: 36925463 PMCID: PMC10011166 DOI: 10.3389/fmicb.2023.1114226] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 02/10/2023] [Indexed: 03/08/2023] Open
Abstract
Instruction: Rift valley fever virus (RVFV) is a mosquito-transmitted bunyavirus that causes severe disease in animals and humans. Nevertheless, there are no vaccines applied to prevent RVFV infection for human at present. Therefore, it is necessary to develop a safe and effective RVFV vaccine. Methods: We generated Ad5-GnGcopt, a replication-deficient recombinant Ad5 vector (human adenovirus serotype 5) expressing codon-optimized RVFV glycoproteins Gn and Gc, and evaluated its immunogenicity and protective efficacy in mice. Results and Discussion: Intramuscular immunization of Ad5-GnGcopt in mice induces strong and durable antibody production and robust cellular immune responses. Additionally, a single vaccination with Ad5-GnGcopt vaccination can completely protect interferon-α/β receptor-deficient A129 mice from lethal RVFV infection. Our work indicates that Ad5-GnGcopt might represent a potential vaccine candidate against RVFV. However, further research is needed, first to confirm its efficacy in a natural animal host, and ultimately escalate as a potential vaccine candidate for humans.
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Affiliation(s)
- Meng Hao
- Vaccine and Antibody Engineer Laboratory, Beijing Institute of Biotechnology, Beijing, China
| | - Ting Bian
- Vaccine and Antibody Engineer Laboratory, Beijing Institute of Biotechnology, Beijing, China
| | - Guangcheng Fu
- Vaccine and Antibody Engineer Laboratory, Beijing Institute of Biotechnology, Beijing, China
| | - Yi Chen
- Vaccine and Antibody Engineer Laboratory, Beijing Institute of Biotechnology, Beijing, China
| | - Ting Fang
- Vaccine and Antibody Engineer Laboratory, Beijing Institute of Biotechnology, Beijing, China
| | - Chuanyi Zhao
- Vaccine and Antibody Engineer Laboratory, Beijing Institute of Biotechnology, Beijing, China
| | - Shuling Liu
- Vaccine and Antibody Engineer Laboratory, Beijing Institute of Biotechnology, Beijing, China
| | - Changming Yu
- Vaccine and Antibody Engineer Laboratory, Beijing Institute of Biotechnology, Beijing, China
| | - Jianmin Li
- Vaccine and Antibody Engineer Laboratory, Beijing Institute of Biotechnology, Beijing, China.,Frontier Biotechnology Laboratory, Zhejiang University-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou, China
| | - Wei Chen
- Vaccine and Antibody Engineer Laboratory, Beijing Institute of Biotechnology, Beijing, China
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12
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Rift Valley Fever Virus Non-Structural Protein S Is Associated with Nuclear Translocation of Active Caspase-3 and Inclusion Body Formation. Viruses 2022; 14:v14112487. [PMID: 36366585 PMCID: PMC9698985 DOI: 10.3390/v14112487] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 11/06/2022] [Accepted: 11/06/2022] [Indexed: 11/12/2022] Open
Abstract
Rift Valley fever phlebovirus (RVFV) causes Rift Valley fever (RVF), an emerging zoonotic disease that causes abortion storms and high mortality rates in young ruminants as well as severe or even lethal complications in a subset of human patients. This study investigates the pathomechanism of intranuclear inclusion body formation in severe RVF in a mouse model. Liver samples from immunocompetent mice infected with virulent RVFV 35/74, and immunodeficient knockout mice that lack interferon type I receptor expression and were infected with attenuated RVFV MP12 were compared to livers from uninfected controls using histopathology and immunohistochemistry for RVFV nucleoprotein, non-structural protein S (NSs) and pro-apoptotic active caspase-3. Histopathology of the livers showed virus-induced, severe hepatic necrosis in both mouse strains. However, immunohistochemistry and immunofluorescence revealed eosinophilic, comma-shaped, intranuclear inclusions and an intranuclear (co-)localization of RVFV NSs and active caspase-3 only in 35/74-infected immunocompetent mice, but not in MP12-infected immunodeficient mice. These results suggest that intranuclear accumulation of RVFV 35/74 NSs is involved in nuclear translocation of active caspase-3, and that nuclear NSs and active caspase-3 are involved in the formation of the light microscopically visible inclusion bodies.
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13
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McMillen CM, Boyles DA, Kostadinov SG, Hoehl RM, Schwarz MM, Albe JR, Demers MJ, Hartman AL. Congenital Rift Valley fever in Sprague Dawley rats is associated with diffuse infection and pathology of the placenta. PLoS Negl Trop Dis 2022; 16:e0010898. [PMID: 36315601 PMCID: PMC9648853 DOI: 10.1371/journal.pntd.0010898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 11/10/2022] [Accepted: 10/17/2022] [Indexed: 11/12/2022] Open
Abstract
Rift Valley fever (RVF) is a disease of animals and humans associated with abortions in ruminants and late-gestation miscarriages in women. Here, we use a rat model of congenital RVF to identify tropisms, pathologies, and immune responses in the placenta during vertical transmission. Infection of late-gestation pregnant rats resulted in vertical transmission to the placenta and widespread infection throughout the decidua, basal zone, and labyrinth zone. Some pups from infected dams appeared normal while others had gross signs of teratogenicity including death. Histopathological lesions were detected in placenta from pups regardless of teratogenicity, while teratogenic pups had widespread hemorrhage throughout multiple placenta layers. Teratogenic events were associated with significant increases in placental pro-inflammatory cytokines, type I interferons, and chemokines. RVFV displays a high degree of tropism for all placental tissue layers and the degree of hemorrhage and inflammatory mediator production is highest in placenta from pups with adverse outcomes. Given the potential for RVFV to emerge in new locations and the recent evidence of emerging viruses, like Zika and SARS-CoV-2, to undergo vertical transmission, this study provides essential understanding regarding the mechanisms by which RVFV crosses the placenta barrier. Rift Valley fever virus (RVFV) infections cause human health and economical burdens given its ability to induce high rates of abortions in ruminants and possible contributions towards late-term miscarriages in women. In this study, we have identified important structures in the placenta targeted by this emerging bunyavirus. Inflammation was associated with more severe fetal outcomes such as death and fetal deformities. The striking similarities between the pathologies of the placenta in the rat model of congenital RVF and those observed in naturally infected ruminants highlight the utility of this rodent model. These findings may be further translated towards understanding the mechanisms involved in vertical transmission of RVFV in humans.
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Affiliation(s)
- Cynthia M. McMillen
- Center for Vaccine Research, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Department of Infectious Diseases and Microbiology, University of Pittsburgh School of Public Health, Pittsburgh, Pennsylvania, United States of America
| | - Devin A. Boyles
- Center for Vaccine Research, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Stefan G. Kostadinov
- Department of Pathology, Magee Women’s Hospital of the University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Ryan M. Hoehl
- Center for Vaccine Research, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Madeline M. Schwarz
- Center for Vaccine Research, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Department of Infectious Diseases and Microbiology, University of Pittsburgh School of Public Health, Pittsburgh, Pennsylvania, United States of America
| | - Joseph R. Albe
- Center for Vaccine Research, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Department of Infectious Diseases and Microbiology, University of Pittsburgh School of Public Health, Pittsburgh, Pennsylvania, United States of America
| | - Matthew J. Demers
- Center for Vaccine Research, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Amy L. Hartman
- Center for Vaccine Research, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Department of Infectious Diseases and Microbiology, University of Pittsburgh School of Public Health, Pittsburgh, Pennsylvania, United States of America
- * E-mail:
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14
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Campbell CL, Snell TK, Bennett S, Wyckoff JH, Heaslip D, Flatt J, Harris EK, Hartman DA, Lian E, Bird BH, Stenglein MD, Bowen RA, Kading RC. Safety study of Rift Valley Fever human vaccine candidate (DDVax) in mosquitoes. Transbound Emerg Dis 2022; 69:2621-2633. [PMID: 34890118 PMCID: PMC9788258 DOI: 10.1111/tbed.14415] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 11/20/2021] [Accepted: 11/30/2021] [Indexed: 12/30/2022]
Abstract
Rift Valley fever virus (RVFV) is a mosquito-borne pathogen with significant human and veterinary health consequences that periodically emerges in epizootics. RVFV causes fetal loss and death in ruminants and in humans can lead to liver and renal disease, delayed-onset encephalitis, retinitis, and in some cases severe haemorrhagic fever. A live attenuated vaccine candidate (DDVax), was developed by the deletion of the virulence factors NSs and NSm from a clinical isolate, ZH501, and has proven safe and immunogenic in rodents, pregnant sheep and non-human primates. Deletion of NSm also severely restricted mosquito midgut infection and inhibited vector-borne transmission. To demonstrate environmental safety, this study investigated the replication, dissemination and transmission efficiency of DDVax in mosquitoes following oral exposure compared to RVFV strains MP-12 and ZH501. Infection and dissemination profiles were also measured in mosquitoes 7 days after they fed on goats inoculated with DDvax or MP-12. We hypothesized that DDVax would infect mosquitoes at significantly lower rates than other RVFV strains and, due to lack of NSm, be transmission incompetent. Exposure of Ae. aegypti and Cx. tarsalis to 8 log10 plaque forming units (PFU)/ml DDVax by artificial bloodmeal resulted in significantly reduced DDVax infection rates in mosquito bodies compared to controls. Plaque assays indicated negligible transmission of infectious DDVax in Cx. tarsalis saliva (1/140 sampled) and none in Ae. aegypti saliva (0/120). Serum from goats inoculated with DDVax or MP-12 did not harbour detectable infectious virus by plaque assay at 1, 2 or 3 days post-inoculation. Infectious virus was, however, recovered from Aedes and Culex bodies that fed on goats vaccinated with MP-12 (13.8% and 4.6%, respectively), but strikingly, DDvax-positive mosquito bodies were greatly reduced (4%, and 0%, respectively). Furthermore, DDVax did not disseminate to legs/wings in any of the goat-fed mosquitoes. Collectively, these results are consistent with a beneficial environmental safety profile.
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Affiliation(s)
- Corey L. Campbell
- Department of MicrobiologyImmunology, and PathologyCenter for Vector‐Borne Infectious DiseasesColorado State UniversityFort CollinsColorado
| | - Trey K. Snell
- Department of MicrobiologyImmunology, and PathologyCenter for Vector‐Borne Infectious DiseasesColorado State UniversityFort CollinsColorado
| | - Susi Bennett
- Department of MicrobiologyImmunology, and PathologyCenter for Vector‐Borne Infectious DiseasesColorado State UniversityFort CollinsColorado
| | - John H. Wyckoff
- BioMARC, Infectious Diseases Research Center, Colorado State UniversityFort CollinsColorado
| | - Darragh Heaslip
- BioMARC, Infectious Diseases Research Center, Colorado State UniversityFort CollinsColorado
| | - Jordan Flatt
- BioMARC, Infectious Diseases Research Center, Colorado State UniversityFort CollinsColorado
| | - Emma K. Harris
- Department of MicrobiologyImmunology, and PathologyCenter for Vector‐Borne Infectious DiseasesColorado State UniversityFort CollinsColorado
| | - Daniel A. Hartman
- Department of MicrobiologyImmunology, and PathologyCenter for Vector‐Borne Infectious DiseasesColorado State UniversityFort CollinsColorado
| | - Elena Lian
- Department of MicrobiologyImmunology, and PathologyCenter for Vector‐Borne Infectious DiseasesColorado State UniversityFort CollinsColorado
| | - Brian H. Bird
- School of Veterinary MedicineOne Health InstituteUniversity of CaliforniaDavisCalifornia
| | - Mark D. Stenglein
- Department of MicrobiologyImmunology, and PathologyCenter for Vector‐Borne Infectious DiseasesColorado State UniversityFort CollinsColorado
| | - Richard A. Bowen
- Department of MicrobiologyImmunology, and PathologyCenter for Vector‐Borne Infectious DiseasesColorado State UniversityFort CollinsColorado
| | - Rebekah C. Kading
- Department of MicrobiologyImmunology, and PathologyCenter for Vector‐Borne Infectious DiseasesColorado State UniversityFort CollinsColorado
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15
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Safety and immunogenicity of four-segmented Rift Valley fever virus in the common marmoset. NPJ Vaccines 2022; 7:54. [PMID: 35585071 PMCID: PMC9117246 DOI: 10.1038/s41541-022-00476-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 04/05/2022] [Indexed: 11/08/2022] Open
Abstract
Rift Valley fever virus (RVFV) is an emerging mosquito-borne bunyavirus that is highly pathogenic to wild and domesticated ruminants, camelids, and humans. While animals are exclusively infected via mosquito bites, humans can also be infected via contact with contaminated tissues or blood. No human vaccine is available and commercialized veterinary vaccines do not optimally combine efficacy with safety. We previously reported the development of two novel live-attenuated RVF vaccines, created by splitting the M genome segment and deleting the major virulence determinant NSs. The vaccine candidates, referred to as the veterinary vaccine vRVFV-4s and the human vaccine hRVFV-4s, were shown to induce protective immunity in multiple species after a single vaccination. Anticipating accidental exposure of humans to the veterinary vaccine and the application of hRVFV-4s to humans, the safety of each vaccine was evaluated in the most susceptible nonhuman primate model, the common marmoset (Callithrix jacchus). Marmosets were inoculated with high doses of each vaccine and were monitored for clinical signs as well as for vaccine virus dissemination, shedding, and spreading to the environment. To accurately assess the attenuation of both vaccine viruses, separate groups of marmosets were inoculated with the parent wild-type RVFV strains. Both wild-type strains induced high viremia and disseminated to primary target organs, associated with mild-to-severe morbidity. In contrast, both vaccines were well tolerated with no evidence of dissemination and shedding while inducing potent neutralizing antibody responses. The results of the studies support the unprecedented safety profile of both vaccines for animals and humans.
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16
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Anywaine Z, Lule SA, Hansen C, Warimwe G, Elliott A. Clinical manifestations of Rift Valley fever in humans: Systematic review and meta-analysis. PLoS Negl Trop Dis 2022; 16:e0010233. [PMID: 35333856 PMCID: PMC8986116 DOI: 10.1371/journal.pntd.0010233] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 04/06/2022] [Accepted: 02/03/2022] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Rift Valley fever (RVF) is an emerging, neglected, mosquito-borne viral zoonosis associated with significant morbidity, mortality and expanding geographical scope. The clinical signs and symptoms in humans are non-specific and case definitions vary. We reviewed and analysed the clinical manifestations of RVF in humans. METHODS In this systematic review and meta-analysis we searched on different dates, the Embase (from 1947 to 13th October 2019), Medline (1946 to 14th October 2019), Global Health (1910 to 15th October 2019), and Web of Science (1970 to 15th October 2019) databases. Studies published in English, reporting frequency of symptoms in humans, and laboratory confirmed RVF were included. Animal studies, studies among asymptomatic volunteers, and single case reports for which a proportion could not be estimated, were excluded. Quality assessment was done using a modified Hoy and Brooks et al tool, data was extracted, and pooled frequency estimates calculated using random effects meta-analysis. RESULTS Of the 3765 articles retrieved, less than 1% (32 articles) were included in the systematic review and meta-analysis. Nine RVF clinical syndromes were reported including the general febrile, renal, gastrointestinal, hepatic, haemorrhagic, visual, neurological, cardio-pulmonary, and obstetric syndromes. The most common clinical manifestations included fever (81%; 95% Confidence Interval (CI) 69-91; [26 studies, 1286 patients]), renal failure (41%; 23-59; [4, 327]), nausea (38%; 12-67; [6, 325]), jaundice (26%; 16-36; [15, 393]), haemorrhagic disease (26%; 17-36; [16, 277]), partial blindness (24%; 7-45; [11, 225]), encephalitis (21%; 11-33; [4, 327]), cough (4%; 0-17; [4, 11]), and miscarriage (54%) respectively. Death occurred in 21% (95% CI 14-29; [16 studies, 328 patients]) of cases, most of whom were hospitalised. DISCUSSION This study delineates the complex symptomatology of human RVF disease into syndromes. This approach is likely to improve case definitions and detection rates, impact outbreak control, increase public awareness about RVF, and subsequently inform 'one-health' policies. This study provides a pooled estimate of the proportion of RVF clinical manifestations alongside a narrative description of clinical syndromes. However, most studies reviewed were case series with small sample sizes and enrolled mostly in-patients and out-patients, and captured symptoms either sparsely or using broad category terms.
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Affiliation(s)
- Zacchaeus Anywaine
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda
- * E-mail:
| | - Swaib Abubaker Lule
- Institute for Global Health, University College London, London, United Kingdom
| | - Christian Hansen
- Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda
- MRC International Statistics & Epidemiology Group, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - George Warimwe
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
- KEMRI WellcomeTrust Research Programme, Kilifi, Kenya
| | - Alison Elliott
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda
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17
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Semmes EC, Coyne CB. Innate immune defenses at the maternal-fetal interface. Curr Opin Immunol 2022; 74:60-67. [PMID: 34768027 PMCID: PMC11063961 DOI: 10.1016/j.coi.2021.10.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 10/12/2021] [Accepted: 10/20/2021] [Indexed: 12/19/2022]
Abstract
The human maternal-fetal interface is an immunologically complex environment that must balance the divergent demands of tolerance towards the developing fetus with anti-pathogen defense. The innate immune responses at the maternal-fetal interface that function in anti-microbial defense have been understudied to-date and how 'TORCH' pathogens evade maternal innate immunity to infect the fetus remains poorly understood. Herein, we discuss how newly described decidual innate lymphoid cells and maternal placenta-associated macrophage subsets may be involved in anti-pathogen defense. Moreover, we outline recent advances in our understanding of how placental trophoblasts and fetal-derived macrophages (Hofbauer cells) function in anti-microbial defense. In summary, we highlight current gaps in knowledge and describe novel experimental models of the human decidua and placenta that are poised to advance our knowledge of innate immune defenses at the maternal-fetal interface.
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Affiliation(s)
- Eleanor C Semmes
- Medical Scientist Training Program, Duke University, Durham, NC, USA; Molecular Genetics and Microbiology Department, Duke University, Durham, NC, USA; Duke Human Vaccine Institute, Duke University, Durham, NC, USA
| | - Carolyn B Coyne
- Molecular Genetics and Microbiology Department, Duke University, Durham, NC, USA; Duke Human Vaccine Institute, Duke University, Durham, NC, USA.
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18
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Uwishema O, Chalhoub E, Torbati T, David SC, Khoury C, Ribeiro LLPA, Nasrallah Y, Bekele BK, Onyeaka H. Rift Valley fever during the COVID-19 pandemic in Africa: A double burden for Africa's healthcare system. Health Sci Rep 2022; 5:e468. [PMID: 35024458 PMCID: PMC8733828 DOI: 10.1002/hsr2.468] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 10/21/2021] [Accepted: 11/09/2021] [Indexed: 02/06/2023] Open
Abstract
A new rising incidence of Rift Valley fever (RVF) among livestock and humans in the African continent during the COVID‐19 pandemic has become of increasing concern. We analyzed the different ways COVID‐19 has contributed to the increase in RVF cases and how it has impacted the interventions allocated to the disease by comparing it with the status of the disease before the pandemic. There is enough evidence to conclude that the COVID‐19 pandemic has impacted the efforts being taken to prevent outbreaks of RVF. Therefore, with no definitive treatment in place and inadequate preventive measures and disease control, RVF may potentially lead to a future epidemic unless addressed urgently.
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Affiliation(s)
- Olivier Uwishema
- Oli Health Magazine Organization Research and Education Kigali Rwanda.,Clinton Global Initiative University Research and Education New York New York USA.,Faculty of Medicine Karadeniz Technical University Trabzon Turkey
| | - Elie Chalhoub
- Oli Health Magazine Organization Research and Education Kigali Rwanda.,Faculty of Medicine University of Saint Joseph of Beirut Beirut Lebanon
| | - Tania Torbati
- Department of Osteopathic Medicine of the Pacific Western University of Health Sciences Pomona California USA
| | - Success Chekwube David
- Oli Health Magazine Organization Research and Education Kigali Rwanda.,Faculty of pharmaceutical Sciences University of Nigeria Enugu Nigeria
| | - Carlo Khoury
- Oli Health Magazine Organization Research and Education Kigali Rwanda.,Faculty of Medicine University of Saint Joseph of Beirut Beirut Lebanon
| | | | - Yves Nasrallah
- Oli Health Magazine Organization Research and Education Kigali Rwanda.,School of Medicine & Medical Sciences Holy Spirit University of Kaslik Beirut Lebanon
| | - Bezawit Kassahun Bekele
- Oli Health Magazine Organization Research and Education Kigali Rwanda.,Addis Ababa University College of Health Science, School of Medicine Addis Ababa Ethiopia
| | - Helen Onyeaka
- School of Chemical Engineering University of Birmingham Birmingham UK
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19
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Viral Infections During Pregnancy: The Big Challenge Threatening Maternal and Fetal Health. MATERNAL-FETAL MEDICINE 2022; 4:72-86. [PMID: 35187500 PMCID: PMC8843053 DOI: 10.1097/fm9.0000000000000133] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 11/11/2021] [Indexed: 12/18/2022] Open
Abstract
Viral infections during pregnancy are associated with adverse pregnancy outcomes, including maternal and fetal mortality, pregnancy loss, premature labor, and congenital anomalies. Mammalian gestation encounters an immunological paradox wherein the placenta balances the tolerance of an allogeneic fetus with protection against pathogens. Viruses cannot easily transmit from mother to fetus due to physical and immunological barriers at the maternal-fetal interface posing a restricted threat to the fetus and newborns. Despite this, the unknown strategies utilized by certain viruses could weaken the placental barrier to trigger severe maternal and fetal health issues especially through vertical transmission, which was not fully understood until now. In this review, we summarize diverse aspects of the major viral infections relevant to pregnancy, including the characteristics of pathogenesis, related maternal-fetal complications, and the underlying molecular and cellular mechanisms of vertical transmission. We highlight the fundamental signatures of complex placental defense mechanisms, which will prepare us to fight the next emerging and re-emerging infectious disease in the pregnancy population.
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20
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Hayashi M, Schultz EP, Lanchy JM, Lodmell JS. Time-Resolved Analysis of N-RNA Interactions during RVFV Infection Shows Qualitative and Quantitative Shifts in RNA Encapsidation and Packaging. Viruses 2021; 13:2417. [PMID: 34960686 PMCID: PMC8704896 DOI: 10.3390/v13122417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/28/2021] [Accepted: 11/29/2021] [Indexed: 11/16/2022] Open
Abstract
Rift Valley fever virus (RVFV) is a negative-sense, tripartite RNA virus that is endemic to Africa and the Arabian Peninsula. It can cause severe disease and mortality in humans and domestic livestock and is a concern for its potential to spread more globally. RVFV's nucleocapsid protein (N) is an RNA-binding protein that is necessary for viral transcription, replication, and the production of nascent viral particles. We have conducted crosslinking, immunoprecipitation, and sequencing (CLIP-seq) to characterize N interactions with host and viral RNAs during infection. In parallel, to precisely measure intracellular N levels, we employed multiple reaction monitoring mass spectrometry (MRM-MS). Our results show that N binds mostly to host RNAs at early stages of infection, yielding nascent virus particles of reduced infectivity. The expression of N plateaus 10 h post-infection, whereas the intracellular viral RNA concentration continues to increase. Moreover, the virions produced later in infection have higher infectivity. Taken together, the detailed examination of these N-RNA interactions provides insight into how the regulated expression of N and viral RNA produces both infectious and incomplete, noninfectious particles.
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Affiliation(s)
- Miyuki Hayashi
- Department of Chemistry and Biochemistry, University of Montana, Missoula, MT 59812, USA;
- Center for Biomolecular Structure and Dynamics, Missoula, MT 59812, USA;
| | - Eric P. Schultz
- Center for Biomolecular Structure and Dynamics, Missoula, MT 59812, USA;
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA;
| | - Jean-Marc Lanchy
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA;
| | - J. Stephen Lodmell
- Center for Biomolecular Structure and Dynamics, Missoula, MT 59812, USA;
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA;
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21
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Rift Valley Fever Virus Propagates in Human Villous Trophoblast Cell Lines and Induces Cytokine mRNA Responses Known to Provoke Miscarriage. Viruses 2021; 13:v13112265. [PMID: 34835071 PMCID: PMC8625252 DOI: 10.3390/v13112265] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/08/2021] [Accepted: 11/10/2021] [Indexed: 02/05/2023] Open
Abstract
The mosquito-borne Rift Valley fever (RVF) is a prioritised disease that has been listed by the World Health Organization for urgent research and development of counteraction. Rift Valley fever virus (RVFV) can cause a cytopathogenic effect in the infected cell and induce hyperimmune responses that contribute to pathogenesis. In livestock, the consequences of RVFV infection vary from mild symptoms to abortion. In humans, 1–3% of patients with RVFV infection develop severe disease, manifested as, for example, haemorrhagic fever, encephalitis or blindness. RVFV infection has also been associated with miscarriage in humans. During pregnancy, there should be a balance between pro-inflammatory and anti-inflammatory mediators to create a protective environment for the placenta and foetus. Many viruses are capable of penetrating that protective environment and infecting the foetal–maternal unit, possibly via the trophoblasts in the placenta, with potentially severe consequences. Whether it is the viral infection per se, the immune response, or both that contribute to the pathogenesis of miscarriage remains unknown. To investigate how RVFV could contribute to pathogenesis during pregnancy, we infected two human trophoblast cell lines, A3 and Jar, representing normal and transformed human villous trophoblasts, respectively. They were infected with two RVFV variants (wild-type RVFV and RVFV with a deleted NSs protein), and the infection kinetics and 15 different cytokines were analysed. The trophoblast cell lines were infected by both RVFV variants and infection caused upregulation of messenger RNA (mRNA) expression for interferon (IFN) types I–III and inflammatory cytokines, combined with cell line-specific mRNA expression of transforming growth factor (TGF)-β1 and interleukin (IL)-10. When comparing the two RVFV variants, we found that infection with RVFV lacking NSs function caused a hyper-IFN response and inflammatory response, while the wild-type RVFV suppressed the IFN I and inflammatory response. The induction of certain cytokines by RVFV infection could potentially lead to teratogenic effects that disrupt foetal and placental developmental pathways, leading to birth defects and other pregnancy complications, such as miscarriage.
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22
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Terasaki K, Kalveram B, Johnson KN, Juelich T, Smith JK, Zhang L, Freiberg AN, Makino S. Rift Valley fever virus 78kDa envelope protein attenuates virus replication in macrophage-derived cell lines and viral virulence in mice. PLoS Negl Trop Dis 2021; 15:e0009785. [PMID: 34516560 PMCID: PMC8460012 DOI: 10.1371/journal.pntd.0009785] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 09/23/2021] [Accepted: 09/02/2021] [Indexed: 12/27/2022] Open
Abstract
Rift Valley fever virus (RVFV) is a mosquito-borne bunyavirus with a wide host range including ruminants and humans. RVFV outbreaks have had devastating effects on public health and the livestock industry in African countries. However, there is no approved RVFV vaccine for human use in non-endemic countries and no FDA-approved antiviral drug for RVFV treatment. The RVFV 78kDa protein (P78), which is a membrane glycoprotein, plays a role in virus dissemination in the mosquito host, but its biological role in mammalian hosts remains unknown. We generated an attenuated RVFV MP-12 strain-derived P78-High virus and a virulent ZH501 strain-derived ZH501-P78-High virus, both of which expressed a higher level of P78 and carried higher levels of P78 in the virion compared to their parental viruses. We also generated another MP-12-derived mutant virus (P78-KO virus) that does not express P78. MP-12 and P78-KO virus replicated to similar levels in fibroblast cell lines and Huh7 cells, while P78-High virus replicated better than MP-12 in Vero E6 cells, fibroblast cell lines, and Huh7 cells. Notably, P78-High virus and P78-KO virus replicated less efficiently and more efficiently, respectively, than MP-12 in macrophage cell lines. ZH501-P78-High virus also replicated poorly in macrophage cell lines. Our data further suggest that inefficient binding of P78-High virus to the cells led to inefficient virus internalization, low virus infectivity and reduced virus replication in a macrophage cell line. P78-High virus and P78-KO virus showed lower and higher virulence than MP-12, respectively, in young mice. ZH501-P78-High virus also exhibited lower virulence than ZH501 in mice. These data suggest that high levels of P78 expression attenuate RVFV virulence by preventing efficient virus replication in macrophages. Genetic alteration leading to increased P78 expression may serve as a novel strategy for the attenuation of RVFV virulence and generation of safe RVFV vaccines.
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Affiliation(s)
- Kaori Terasaki
- Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, Texas, United States of America
- Institute of Human Infection and Immunity, The University of Texas Medical Branch, Galveston, Texas, United States of America
- * E-mail: (KT); (SM)
| | - Birte Kalveram
- Department of Pathology, The University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Kendra N. Johnson
- Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Terry Juelich
- Department of Pathology, The University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Jennifer K. Smith
- Department of Pathology, The University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Lihong Zhang
- Department of Pathology, The University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Alexander N. Freiberg
- Institute of Human Infection and Immunity, The University of Texas Medical Branch, Galveston, Texas, United States of America
- Department of Pathology, The University of Texas Medical Branch, Galveston, Texas, United States of America
- Center for Biodefense and Emerging Infectious Diseases, the University of Texas Medical Branch, Galveston, Texas, United States of America
- Center for Tropical Diseases, The University of Texas Medical Branch, Galveston, Texas, United States of America
- Sealy Institute for Vaccine Sciences, The University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Shinji Makino
- Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, Texas, United States of America
- Institute of Human Infection and Immunity, The University of Texas Medical Branch, Galveston, Texas, United States of America
- Center for Biodefense and Emerging Infectious Diseases, the University of Texas Medical Branch, Galveston, Texas, United States of America
- Center for Tropical Diseases, The University of Texas Medical Branch, Galveston, Texas, United States of America
- Sealy Institute for Vaccine Sciences, The University of Texas Medical Branch, Galveston, Texas, United States of America
- * E-mail: (KT); (SM)
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23
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Megli CJ, Coyne CB. Infections at the maternal-fetal interface: an overview of pathogenesis and defence. Nat Rev Microbiol 2021; 20:67-82. [PMID: 34433930 PMCID: PMC8386341 DOI: 10.1038/s41579-021-00610-y] [Citation(s) in RCA: 142] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/15/2021] [Indexed: 02/08/2023]
Abstract
Infections are a major threat to human reproductive health, and infections in pregnancy can cause prematurity or stillbirth, or can be vertically transmitted to the fetus leading to congenital infection and severe disease. The acronym ‘TORCH’ (Toxoplasma gondii, other, rubella virus, cytomegalovirus, herpes simplex virus) refers to pathogens directly associated with the development of congenital disease and includes diverse bacteria, viruses and parasites. The placenta restricts vertical transmission during pregnancy and has evolved robust mechanisms of microbial defence. However, microorganisms that cause congenital disease have likely evolved diverse mechanisms to bypass these defences. In this Review, we discuss how TORCH pathogens access the intra-amniotic space and overcome the placental defences that protect against microbial vertical transmission. Infections during pregnancy can be associated with devastating outcomes for the pregnant mother and developing fetus. In this Review, Megli and Coyne discuss placental defences and provide an overview of how various viral, bacterial and parasitic pathogens traverse the maternal–fetal interface and cause disease.
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Affiliation(s)
- Christina J Megli
- Division of Maternal-Fetal Medicine, Division of Reproductive Infectious Disease, Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine and the Magee Womens Research Institute, Pittsburgh, PA, USA.
| | - Carolyn B Coyne
- Department of Molecular Genetics and Microbiology and the Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA.
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24
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Odendaal L, Davis AS, Venter EH. Insights into the Pathogenesis of Viral Haemorrhagic Fever Based on Virus Tropism and Tissue Lesions of Natural Rift Valley Fever. Viruses 2021; 13:v13040709. [PMID: 33923863 PMCID: PMC8073615 DOI: 10.3390/v13040709] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 03/26/2021] [Accepted: 04/02/2021] [Indexed: 12/20/2022] Open
Abstract
Rift Valley fever phlebovirus (RVFV) infects humans and a wide range of ungulates and historically has caused devastating epidemics in Africa and the Arabian Peninsula. Lesions of naturally infected cases of Rift Valley fever (RVF) have only been described in detail in sheep with a few reports concerning cattle and humans. The most frequently observed lesion in both ruminants and humans is randomly distributed necrosis, particularly in the liver. Lesions supportive of vascular endothelial injury are also present and include mild hydropericardium, hydrothorax and ascites; marked pulmonary congestion and oedema; lymph node congestion and oedema; and haemorrhages in many tissues. Although a complete understanding of RVF pathogenesis is still lacking, antigen-presenting cells in the skin are likely the early targets of the virus. Following suppression of type I IFN production and necrosis of dermal cells, RVFV spreads systemically, resulting in infection and necrosis of other cells in a variety of organs. Failure of both the innate and adaptive immune responses to control infection is exacerbated by apoptosis of lymphocytes. An excessive pro-inflammatory cytokine and chemokine response leads to microcirculatory dysfunction. Additionally, impairment of the coagulation system results in widespread haemorrhages. Fatal outcomes result from multiorgan failure, oedema in many organs (including the lungs and brain), hypotension, and circulatory shock. Here, we summarize current understanding of RVF cellular tropism as informed by lesions caused by natural infections. We specifically examine how extant knowledge informs current understanding regarding pathogenesis of the haemorrhagic fever form of RVF, identifying opportunities for future research.
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Affiliation(s)
- Lieza Odendaal
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria 0002, South Africa
- Correspondence: (L.O.); (A.S.D.)
| | - A Sally Davis
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria 0002, South Africa
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
- Correspondence: (L.O.); (A.S.D.)
| | - Estelle H Venter
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Pretoria 0002, South Africa;
- College of Public Health Medical and Veterinary Sciences, Discipline Veterinary Science, James Cook University, Townsville, QLD 4811, Australia
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25
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Rift Valley Fever: a Threat to Pregnant Women Hiding in Plain Sight? J Virol 2021; 95:JVI.01394-19. [PMID: 33597209 DOI: 10.1128/jvi.01394-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 01/30/2021] [Indexed: 12/18/2022] Open
Abstract
The potential for emerging mosquito-borne viruses to cause fetal infection in pregnant women was overlooked until the Zika fever outbreak several years ago. Rift Valley fever virus (RVFV) is an emerging arbovirus with a long history of fetal infection and death in pregnant livestock. The effect of RVFV infection on pregnant women is not well understood. This Gem examines the effects that this important emerging pathogen has during pregnancy, its potential impact on pregnant women, and the current research efforts designed to understand and mitigate adverse effects of RVFV infection during pregnancy.
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26
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Wichgers Schreur PJ, Vloet RPM, Kant J, van Keulen L, Gonzales JL, Visser TM, Koenraadt CJM, Vogels CBF, Kortekaas J. Reproducing the Rift Valley fever virus mosquito-lamb-mosquito transmission cycle. Sci Rep 2021; 11:1477. [PMID: 33446733 PMCID: PMC7809480 DOI: 10.1038/s41598-020-79267-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 11/30/2020] [Indexed: 01/25/2023] Open
Abstract
Rift Valley fever virus (RVFV) is a mosquito-borne bunyavirus that is pathogenic to ruminants and humans. The virus is endemic to Africa and the Arabian Peninsula where outbreaks are characterized by abortion storms and mortality of newborns, particularly in sheep herds. Vector competence experiments in laboratory settings have suggested that over 50 mosquito species are capable of transmitting RVFV. Transmission of mosquito-borne viruses in the field is however influenced by numerous factors, including population densities, blood feeding behavior, extrinsic incubation period, longevity of vectors, and viremia levels in vertebrate hosts. Animal models to study these important aspects of RVFV transmission are currently lacking. In the present work, RVFV was transmitted to European (Texel-swifter cross-breed) lambs by laboratory-reared Aedes aegypti mosquitoes that were infected either by membrane feeding on a virus-spiked blood meal or by feeding on lambs that developed viremia after intravenous inoculation of RVFV. Feeding of mosquitoes on viremic lambs resulted in strikingly higher infection rates as compared to membrane feeding. Subsequent transmission of RVFV from lamb to lamb by infected mosquitoes was highly efficient in both models. The animal models described here can be used to study mosquito-mediated transmission of RVFV among the major natural target species and to evaluate the efficacy of vaccines against mosquito-mediated RVFV infection.
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Affiliation(s)
| | | | - Jet Kant
- Wageningen Bioveterinary Research, Lelystad, The Netherlands
| | | | - Jose L Gonzales
- Wageningen Bioveterinary Research, Lelystad, The Netherlands
| | - Tessa M Visser
- Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands
| | | | - Chantal B F Vogels
- Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands.,Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA
| | - Jeroen Kortekaas
- Wageningen Bioveterinary Research, Lelystad, The Netherlands. .,Laboratory of Virology, Wageningen University & Research, Wageningen, The Netherlands.
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A single vaccination with four-segmented rift valley fever virus prevents vertical transmission of the wild-type virus in pregnant ewes. NPJ Vaccines 2021; 6:8. [PMID: 33420095 PMCID: PMC7794363 DOI: 10.1038/s41541-020-00271-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 12/07/2020] [Indexed: 11/24/2022] Open
Abstract
Rift Valley fever virus (RVFV) is a mosquito-transmitted bunyavirus that causes severe outbreaks among wild and domesticated ruminants, of which sheep are the most susceptible. Outbreaks are characterised by high mortality rates among new-born lambs and abortion storms, in which all pregnant ewes in a flock may abort their foetuses. In endemic areas, Rift Valley fever (RVF) can be controlled by vaccination with either inactivated or live-attenuated vaccines. Inactivated vaccines are safe for animals during all physiological stages, including pregnancy. However, optimal efficacy of these vaccines depends on multiple vaccinations and yearly re-vaccination. Live-attenuated vaccines are generally highly efficacious after a single vaccination, but currently available live-attenuated vaccines may transmit to the ovine foetus, resulting in stillbirths, congenital malformations or abortion. We have previously reported the development of a novel live-attenuated RVFV vaccine, named RVFV-4s. This vaccine virus was created by splitting the M genome segment and deleting the major virulence determinant NSs, and was shown to be safe even for the most susceptible species, including pregnant ewes. The demonstrated efficacy and safety profile suggests that RVFV-4s holds promise for veterinary and human application. The RVFV-4s vaccine for veterinary application, here referred to as vRVFV-4s, was shown to provide complete protection after a single vaccination of lambs, goats and cattle. In this work, we evaluated the efficacy of the vRVFV-4s vaccine in pregnant ewes. Anticipating on the extremely high susceptibility of pregnant ewes for RVFV, both a single vaccination and double vaccination were evaluated in two independent experiments. The combined results suggest that a single vaccination with vRVFV-4s is sufficient to protect pregnant ewes and to prevent transmission to the ovine foetus.
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28
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Oymans J, van Keulen L, Vermeulen GM, Wichgers Schreur PJ, Kortekaas J. Shuni Virus Replicates at the Maternal-Fetal Interface of the Ovine and Human Placenta. Pathogens 2020; 10:pathogens10010017. [PMID: 33383649 PMCID: PMC7823754 DOI: 10.3390/pathogens10010017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Revised: 12/18/2020] [Accepted: 12/24/2020] [Indexed: 11/30/2022] Open
Abstract
Shuni virus (SHUV) is a neglected teratogenic and neurotropic orthobunyavirus that was discovered in the 1960s in Nigeria and was subsequently detected in South Africa, Zimbabwe, and Israel. The virus was isolated from field-collected biting midges and mosquitoes and shown to disseminate efficiently in laboratory-reared biting midges, suggesting that members of the families Culicidae and Ceratopogonidae may function as vectors. SHUV infections have been associated with severe neurological disease in horses, a variety of wildlife species, and domesticated ruminants. SHUV infection of ruminants is additionally associated with abortion, stillbirth, and congenital malformations. The detection of antibodies in human sera also suggests that the virus may have zoonotic potential. To understand how SHUV crosses the ruminant placenta, we here infected pregnant ewes and subsequently performed detailed clinical- and histopathological examination of placental tissue. We found that SHUV targets both maternal epithelial cells and fetal trophoblasts, that together form the maternal-fetal interface of the ovine placenta. Experiments with human placental explants, furthermore, revealed replication of SHUV in syncytiotrophoblasts, which are generally highly resistant to virus infections. Our findings provide novel insights into vertical transmission of SHUV in sheep and call for research on the potential risk of SHUV infection during human pregnancies.
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Affiliation(s)
- Judith Oymans
- Department of Virology, Wageningen Bioveterinary Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (J.O.); (L.v.K.); (P.J.W.S.)
- Laboratory of Virology, Wageningen University & Research, P.O. Box 16, 6700 AA Wageningen, The Netherlands
| | - Lucien van Keulen
- Department of Virology, Wageningen Bioveterinary Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (J.O.); (L.v.K.); (P.J.W.S.)
| | - Guus M. Vermeulen
- Department of Gynaecology, Isala Hospital, 8025 AB Zwolle, The Netherlands;
| | - Paul J. Wichgers Schreur
- Department of Virology, Wageningen Bioveterinary Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (J.O.); (L.v.K.); (P.J.W.S.)
| | - Jeroen Kortekaas
- Department of Virology, Wageningen Bioveterinary Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (J.O.); (L.v.K.); (P.J.W.S.)
- Laboratory of Virology, Wageningen University & Research, P.O. Box 16, 6700 AA Wageningen, The Netherlands
- Correspondence:
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Boumart Z, Bamouh Z, Hamdi J, Safini N, Tadlaoui K, Bettinger G, Watts D, Elharrak M. Safety and immunogenicity of the Rift Valley fever arMP-12 ΔNSm21/384 candidate vaccine in pregnant ewes. Vaccine X 2020; 6:100070. [PMID: 32793877 PMCID: PMC7415414 DOI: 10.1016/j.jvacx.2020.100070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/24/2020] [Accepted: 07/26/2020] [Indexed: 11/18/2022] Open
Abstract
Rift Valley fever virus causes abortion, teratogenicity and mortality in domestic ruminants. Safety and immunogenicity RVFV arMP-12ΔNSm21/384 vaccine was determined in pregnant ewes. Vaccine was safe and immunogenic last stages of pregnancy, but may caused malformed lambs early stage. Pregnant sheep should not be vaccinated with the RVFV vaccine during the first month of gestation.
Rift Valley fever (RVF) poses a threat to human and animal health as well as economic losses due to abortion, new-born teratogenic effect and mortality. Safe and effective vaccines are critically needed to prevent the disease in humans and livestock. The objective of this study was to assess safety and immunogenicity of the Rift Valley fever virus (RVFV) arMP-12DNSm21/384 attenuated vaccine in 32 pregnant ewes at different stages of pregnancy including 17 ewes vaccinated during the early stage (G1) of pregnancy (<35 days) and 15 ewes vaccinated during the last two stages (G2) of pregnancy (>35 days). Ewes were monitored for clinical observations, rectal temperature and abortions and lambs were monitored for general health and rectal temperature. Vaccinated ewes and lambs were periodically sampled for their neutralizing antibody response to RVFV vaccination. All ewes were positive for antibody two weeks post-vaccination and 79% of ewes were positive at delivery. None of the 32 ewes aborted during pregnancy and all ewes vaccinated during the G2 stages of pregnancy gave birth to healthy lambs. However, among the 17 ewes vaccinated during the G1 stage of pregnancy, 2 ewes gave birth to 2 lambs with fore limb malformations that died at 1-day of age. One ewe gave birth to 2 punny twins that died at 2 days of age. Another ewe, gave birth to one lamb with a deformed tail that died at 20 days of age. At post-mortem, tissues of dead lambs (spleen, lung, brain and long bone) were negative for RVFV by PCR assay. While the findings did not link the malformed lambs directly to infection by the vaccine virus, these results indicated that pregnant sheep should not be vaccinated with the RVFV arMP-12DNSm21/384 vaccine during the first month of gestation.
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Affiliation(s)
- Z. Boumart
- Research and Development Dept., Multi-Chemical Industry, Lot. 157, Z I, Sud-Ouest (ERAC) B.P.: 278, Mohammedia 28810, Morocco
| | - Z. Bamouh
- Research and Development Dept., Multi-Chemical Industry, Lot. 157, Z I, Sud-Ouest (ERAC) B.P.: 278, Mohammedia 28810, Morocco
| | - J. Hamdi
- Research and Development Dept., Multi-Chemical Industry, Lot. 157, Z I, Sud-Ouest (ERAC) B.P.: 278, Mohammedia 28810, Morocco
| | - N. Safini
- Research and Development Dept., Multi-Chemical Industry, Lot. 157, Z I, Sud-Ouest (ERAC) B.P.: 278, Mohammedia 28810, Morocco
| | - K.O. Tadlaoui
- Research and Development Dept., Multi-Chemical Industry, Lot. 157, Z I, Sud-Ouest (ERAC) B.P.: 278, Mohammedia 28810, Morocco
| | - G. Bettinger
- Department of Biological Sciences, University of Texas at El Paso, El Paso, TX 79968, United States
| | - D.M. Watts
- Department of Biological Sciences, University of Texas at El Paso, El Paso, TX 79968, United States
- Corresponding author.
| | - M. Elharrak
- Research and Development Dept., Multi-Chemical Industry, Lot. 157, Z I, Sud-Ouest (ERAC) B.P.: 278, Mohammedia 28810, Morocco
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30
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Odendaal L, Clift SJ, Fosgate GT, Davis AS. Ovine Fetal and Placental Lesions and Cellular Tropism in Natural Rift Valley Fever Virus Infections. Vet Pathol 2020; 57:791-806. [PMID: 32885745 DOI: 10.1177/0300985820954549] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Infection with Rift Valley fever phlebovirus (RVFV) causes abortion storms and a wide variety of outcomes for both ewes and fetuses. Sheep fetuses and placenta specimens were examined during the 2010-2011 River Valley fever (RVF) outbreak in South Africa. A total of 72 fetuses were studied of which 58 were confirmed positive for RVF. Placenta specimens were available for 35 cases. Macroscopic lesions in fetuses were nonspecific and included marked edema and occasional hemorrhages in visceral organs. Microscopically, multifocal hepatic necrosis was present in 48 of 58 cases, and apoptotic bodies, foci of liquefactive hepatic necrosis (primary foci), and eosinophilic intranuclear inclusions in hepatocytes were useful diagnostic features. Lymphocytolysis was present in all lymphoid organs examined with the exception of thymus and Peyer's patches, and pyknosis or karyorrhexis was often present in renal glomeruli. The most significant histologic lesion in the placenta was necrosis of trophoblasts and endothelial cells in the cotyledonary and intercotyledonary chorioallantois. Immunolabeling for RVFV was most consistent in trophoblasts of the cotyledon or caruncle. Other antigen-positive cells included hepatocytes, renal tubular epithelial, juxtaglomerular and extraglomerular mesangial cells, vascular smooth muscle, endothelial and adrenocortical cells, cardiomyocytes, Purkinje fibers, and macrophages. Fetal organ samples for diagnosis must minimally include liver, kidney, and spleen. From the placenta, the minimum recommended specimens for histopathology include the cotyledonary units and caruncles from the endometrium, if available. The diagnostic investigation of abortion in endemic areas should always include routine testing for RVFV, and a diagnosis during interepidemic periods might be missed if only limited specimens are available for examination.
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Affiliation(s)
- Lieza Odendaal
- 56410University of Pretoria, Onderstepoort, Pretoria, South Africa
| | - Sarah J Clift
- 56410University of Pretoria, Onderstepoort, Pretoria, South Africa
| | | | - A Sally Davis
- 56410University of Pretoria, Onderstepoort, Pretoria, South Africa.,5308Kansas State University, Manhattan, KS, USA
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31
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Kroeker AL, Babiuk S, Pickering BS, Richt JA, Wilson WC. Livestock Challenge Models of Rift Valley Fever for Agricultural Vaccine Testing. Front Vet Sci 2020; 7:238. [PMID: 32528981 PMCID: PMC7266933 DOI: 10.3389/fvets.2020.00238] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 04/07/2020] [Indexed: 11/13/2022] Open
Abstract
Since the discovery of Rift Valley Fever virus (RVFV) in Kenya in 1930, the virus has become widespread throughout most of Africa and is characterized by sporadic outbreaks. A mosquito-borne pathogen, RVFV is poised to move beyond the African continent and the Middle East and emerge in Europe and Asia. There is a risk that RVFV could also appear in the Americas, similar to the West Nile virus. In light of this potential threat, multiple studies have been undertaken to establish international surveillance programs and diagnostic tools, develop models of transmission dynamics and risk factors for infection, and to develop a variety of vaccines as countermeasures. Furthermore, considerable efforts to establish reliable challenge models of Rift Valley fever virus have been made and platforms for testing potential vaccines and therapeutics in target species have been established. This review emphasizes the progress and insights from a North American perspective to establish challenge models in target livestock such as cattle, sheep, and goats in comparisons to other researchers' reports. A brief summary of the potential role of wildlife, such as buffalo and white-tailed deer as reservoir species will also be discussed.
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Affiliation(s)
- Andrea Louise Kroeker
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB, Canada
| | - Shawn Babiuk
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB, Canada.,Department of Immunology, University of Manitoba, Winnipeg, MB, Canada
| | - Bradley S Pickering
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB, Canada.,Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada
| | - Juergen A Richt
- Center of Excellence for Emerging and Zoonotic Animal Diseases (CEEZAD), Manhattan, KS, United States
| | - William C Wilson
- USDA, Arthropod-Borne Animal Diseases Research Unit (ABADRU), Manhattan, KS, United States
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32
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Grossi-Soyster EN, LaBeaud AD. Rift Valley Fever: Important Considerations for Risk Mitigation and Future Outbreaks. Trop Med Infect Dis 2020; 5:tropicalmed5020089. [PMID: 32498264 PMCID: PMC7345646 DOI: 10.3390/tropicalmed5020089] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 05/22/2020] [Accepted: 05/28/2020] [Indexed: 12/02/2022] Open
Abstract
Rift Valley fever virus (RVFV) is a zoonotic phlebovirus of the Phenuiviridae family with great opportunity for emergence in previously unaffected regions, despite its current geographical limits. Outbreaks of RVFV often infect humans or domesticated animals, such as livestock, concurrently and occur sporadically, ranging from localized outbreaks in villages to multi-country events that spread rapidly. The true burden of Rift Valley fever (RVF) is not well defined due to underreporting, misdiagnosis caused by the broad spectrum of disease presentation, and minimal access for rapid and accurate laboratory confirmation. Severe symptoms may include hemorrhagic fever, loss of vision, psychological impairment or disturbances, and organ failure. Those living in endemic areas and travelers should be aware of the potential for exposure to ongoing outbreaks or interepidemic transmission, and engage in behaviors to minimize exposure risks, as vaccinations in humans are currently unavailable and animal vaccinations are not used routinely or ubiquitously. The lack of vaccines approved for use in humans is concerning, as RVFV has proven to be highly pathogenic in naïve populations, causing severe disease in a large percent of confirmed cases, which could have considerable impact on human health.
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33
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Oymans J, van Keulen L, Wichgers Schreur PJ, Kortekaas J. Early Pathogenesis of Wesselsbron Disease in Pregnant Ewes. Pathogens 2020; 9:pathogens9050373. [PMID: 32414152 PMCID: PMC7281025 DOI: 10.3390/pathogens9050373] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/24/2020] [Accepted: 05/09/2020] [Indexed: 12/11/2022] Open
Abstract
Wesselsbron virus (WSLV) is a neglected, mosquito-borne flavivirus that is endemic to the African continent. The virus is teratogenic to ruminants and causes a self-limiting febrile illness in humans. Wesselsbron disease manifests with similar clinical signs and occurs in the same areas under the same climatic conditions as Rift Valley fever, which is therefore included in the differential diagnosis. Although the gross pathology of WSLV infection in pregnant ewes is reported in literature, the pathogenesis that leads to stillbirths, congenital malformations and abortion has remained undescribed. In the present study, pregnant ewes were inoculated with WSLV and subjected to detailed clinical- and histopathology 8 days later. The virus was mainly detected in foetal trophoblasts of the placenta and in neural progenitor cells, differentiated neurons, oligodendrocytes, microglia and astrocytes. Our study demonstrates that WSLV efficiently crosses the maternal-foetal interface and is highly neuroinvasive in the ovine foetus.
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Affiliation(s)
- Judith Oymans
- Department of Virology, Wageningen Bioveterinary Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (J.O.); (L.v.K.); (P.J.W.S.)
- Laboratory of Virology, Wageningen University & Research, P.O. Box 16, 6700 AA Wageningen, The Netherlands
| | - Lucien van Keulen
- Department of Virology, Wageningen Bioveterinary Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (J.O.); (L.v.K.); (P.J.W.S.)
| | - Paul J. Wichgers Schreur
- Department of Virology, Wageningen Bioveterinary Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (J.O.); (L.v.K.); (P.J.W.S.)
| | - Jeroen Kortekaas
- Department of Virology, Wageningen Bioveterinary Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (J.O.); (L.v.K.); (P.J.W.S.)
- Laboratory of Virology, Wageningen University & Research, P.O. Box 16, 6700 AA Wageningen, The Netherlands
- Correspondence: ; Tel.: +31-6-20919110
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Oymans J, Wichgers Schreur PJ, van Oort S, Vloet R, Venter M, Pijlman GP, van Oers MM, Kortekaas J. Reverse Genetics System for Shuni Virus, an Emerging Orthobunyavirus with Zoonotic Potential. Viruses 2020; 12:E455. [PMID: 32316542 PMCID: PMC7232226 DOI: 10.3390/v12040455] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/14/2020] [Accepted: 04/15/2020] [Indexed: 01/10/2023] Open
Abstract
The genus Orthobunyavirus (family Peribunyaviridae, order Bunyavirales) comprises over 170 named mosquito- and midge-borne viruses, several of which cause severe disease in animals or humans. Their three-segmented genomes enable reassortment with related viruses, which may result in novel viruses with altered host or tissue tropism and virulence. One such reassortant, Schmallenberg virus (SBV), emerged in north-western Europe in 2011. Shuni virus (SHUV) is an orthobunyavirus related to SBV that is associated with neurological disease in horses in southern Africa and recently caused an outbreak manifesting with neurological disease and birth defects among ruminants in Israel. The zoonotic potential of SHUV was recently underscored by its association with neurological disease in humans. We here report a reverse genetics system for SHUV and provide first evidence that the non-structural (NSs) protein of SHUV functions as an antagonist of host innate immune responses. We furthermore report the rescue of a reassortant containing the L and S segments of SBV and the M segment of SHUV. This novel reverse genetics system can now be used to study SHUV virulence and tropism, and to elucidate the molecular mechanisms that drive reassortment events.
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Affiliation(s)
- Judith Oymans
- Department of Virology, Wageningen Bioveterinary Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (J.O.); (P.J.W.S.); (S.v.O.); (R.V.)
- Laboratory of Virology, Wageningen University & Research, P.O. Box 16, 6700 AA Wageningen, The Netherlands; (G.P.P.); (M.M.v.O.)
| | - Paul J. Wichgers Schreur
- Department of Virology, Wageningen Bioveterinary Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (J.O.); (P.J.W.S.); (S.v.O.); (R.V.)
| | - Sophie van Oort
- Department of Virology, Wageningen Bioveterinary Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (J.O.); (P.J.W.S.); (S.v.O.); (R.V.)
| | - Rianka Vloet
- Department of Virology, Wageningen Bioveterinary Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (J.O.); (P.J.W.S.); (S.v.O.); (R.V.)
| | - Marietjie Venter
- Department Medical Virology, Faculty of Health Science, Centre for Viral Zoonoses, University of Pretoria, Pretoria 0028, South Africa;
| | - Gorben P. Pijlman
- Laboratory of Virology, Wageningen University & Research, P.O. Box 16, 6700 AA Wageningen, The Netherlands; (G.P.P.); (M.M.v.O.)
| | - Monique M. van Oers
- Laboratory of Virology, Wageningen University & Research, P.O. Box 16, 6700 AA Wageningen, The Netherlands; (G.P.P.); (M.M.v.O.)
| | - Jeroen Kortekaas
- Department of Virology, Wageningen Bioveterinary Research, Houtribweg 39, 8221 RA Lelystad, The Netherlands; (J.O.); (P.J.W.S.); (S.v.O.); (R.V.)
- Laboratory of Virology, Wageningen University & Research, P.O. Box 16, 6700 AA Wageningen, The Netherlands; (G.P.P.); (M.M.v.O.)
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Abstract
Rift Valley fever (RVF) is a mosquito-borne viral disease, principally of ruminants, that is endemic to Africa. The causative Phlebovirus, Rift Valley fever virus (RVFV), has a broad host range and, as such, also infects humans to cause primarily a self-limiting febrile illness. A small number of human cases will also develop severe complications, including haemorrhagic fever, encephalitis and visual impairment. In parts of Africa, it is a major disease of domestic ruminants, causing epidemics of abortion and mortality. It infects and can be transmitted by a broad range of mosquitos, with those of the genus Aedes and Culex thought to be the major vectors. Therefore, the virus has the potential to become established beyond Africa, including in Australia, where competent vector hosts are endemic. Vaccines for humans have not yet been developed to the commercial stage. This review examines the threat of this virus, with particular reference to Australia, and assesses gaps in our knowledge that may benefit from research focus.
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