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Chemison A, Ramstein G, Jones A, Morse A, Caminade C. Ability of a dynamical climate sensitive disease model to reproduce historical Rift Valley Fever outbreaks over Africa. Sci Rep 2024; 14:3904. [PMID: 38365824 PMCID: PMC10873308 DOI: 10.1038/s41598-024-53774-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 02/05/2024] [Indexed: 02/18/2024] Open
Abstract
Rift Valley Fever (RVF) is a zoonosis transmitted by Aedes and Culex mosquitoes, and is considered a priority pathogen by the WHO. RVF epidemics mostly occur in Africa and can decimate livestock herds, causing significant economic losses and posing health risks for humans. RVF transmission is associated with the occurrence of El Niño events that cause floods in eastern Africa and favour the emergence of mosquitoes in wetlands. Different risk models have been developed to forecast RVF transmission risk but very few studies have validated models at pan-African scale. This study aims to validate the skill of the Liverpool Rift Valley Fever model (LRVF) in reproducing RVF epidemics over Africa and to explore the relationship between simulated climatic suitability for RVF transmission and large-scale climate modes of variability such as the El Niño Southern Oscillation (ENSO) and the Dipole Mode Index (DMI). Our results show that the LRVF model correctly simulates RVF transmission hotspots and reproduces large epidemics that affected African countries. LRVF was able to correctly reproduce major RVF epidemics in Somalia, Kenya, Zambia and to a lesser extent for Mauritania and Senegal. The positive phases of ENSO and DMI are associated with an increased risk of RVF over the Horn of Africa, with important time lags. Following research activities should focus on the development of predictive modelling systems at different time scales.
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Affiliation(s)
- Alizée Chemison
- Laboratoire des Sciences du Climat et de l'Environnement (LSCE), CEA, CNRS, UVSQ, 91190, Gif-sur-Yvette, France
| | - Gilles Ramstein
- Laboratoire des Sciences du Climat et de l'Environnement (LSCE), CEA, CNRS, UVSQ, 91190, Gif-sur-Yvette, France
| | - Anne Jones
- IBM Research Laboratory, Daresbury, WA4 4AD, UK
| | - Andy Morse
- Department of Geography and Planning, School of Environmental Sciences, University of Liverpool, Liverpool, L69 7ZT, UK
| | - Cyril Caminade
- Earth System Physics, Abdus Salam International Centre for Theoretical Physics, 34151, Trieste, Italy.
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2
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El Ghassem A, Abdoullah B, Deida J, Ould Lemrabott MA, Ouldabdallahi Moukah M, Ould Ahmedou Salem MS, Briolant S, Basco LK, Ould Brahim K, Ould Mohamed Salem Boukhary A. Arthropod-Borne Viruses in Mauritania: A Literature Review. Pathogens 2023; 12:1370. [PMID: 38003834 PMCID: PMC10675338 DOI: 10.3390/pathogens12111370] [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: 10/20/2023] [Revised: 11/13/2023] [Accepted: 11/16/2023] [Indexed: 11/26/2023] Open
Abstract
During the past four decades, recurrent outbreaks of various arthropod-borne viruses have been reported in Mauritania. This review aims to consolidate the current knowledge on the epidemiology of the major arboviruses circulating in Mauritania. Online databases including PubMed and Web of Science were used to retrieve relevant published studies. The results showed that numerous arboviral outbreaks of variable magnitude occurred in almost all 13 regions of Mauritania, with Rift Valley fever (RVF), Crimean-Congo hemorrhagic fever (CCHF), and dengue (DEN) being the most common infections. Other arboviruses causing yellow fever (YF), chikungunya (CHIK), o'nyong-nyong (ONN), Semliki Forest (SF), West Nile fever (WNF), Bagaza (BAG), Wesselsbron (WSL), and Ngari (NRI) diseases have also been found circulating in humans and/or livestock in Mauritania. The average case fatality rates of CCHF and RVF were 28.7% and 21.1%, respectively. RVF outbreaks have often occurred after unusually heavy rainfalls, while CCHF epidemics have mostly been reported during the dry season. The central and southeastern regions of the country have carried the highest burden of RVF and CCHF. Sheep, cattle, and camels are the main animal reservoirs for the RVF and CCHF viruses. Culex antennatus and Cx. poicilipes mosquitoes and Hyalomma dromedarii, H. rufipes, and Rhipicephalus everesti ticks are the main vectors of these viruses. DEN outbreaks occurred mainly in the urban settings, including in Nouakchott, the capital city, and Aedes aegypti is likely the main mosquito vector. Therefore, there is a need to implement an integrated management strategy for the prevention and control of arboviral diseases based on sensitizing the high-risk occupational groups, such as slaughterhouse workers, shepherds, and butchers for zoonotic diseases, reinforcing vector surveillance and control, introducing rapid point-of-care diagnosis of arboviruses in high-risk areas, and improving the capacities to respond rapidly when the first signs of disease outbreak are identified.
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Affiliation(s)
- Abdallahi El Ghassem
- Unité de Recherche Génomes et Milieux, Faculté des Sciences et Techniques, Université de Nouakchott, Nouakchott BP 880, Mauritania; (A.E.G.); (B.A.); (J.D.); (M.A.O.L.); (M.O.M.); (M.S.O.A.S.); (K.O.B.)
| | - Bedia Abdoullah
- Unité de Recherche Génomes et Milieux, Faculté des Sciences et Techniques, Université de Nouakchott, Nouakchott BP 880, Mauritania; (A.E.G.); (B.A.); (J.D.); (M.A.O.L.); (M.O.M.); (M.S.O.A.S.); (K.O.B.)
| | - Jemila Deida
- Unité de Recherche Génomes et Milieux, Faculté des Sciences et Techniques, Université de Nouakchott, Nouakchott BP 880, Mauritania; (A.E.G.); (B.A.); (J.D.); (M.A.O.L.); (M.O.M.); (M.S.O.A.S.); (K.O.B.)
| | - Mohamed Aly Ould Lemrabott
- Unité de Recherche Génomes et Milieux, Faculté des Sciences et Techniques, Université de Nouakchott, Nouakchott BP 880, Mauritania; (A.E.G.); (B.A.); (J.D.); (M.A.O.L.); (M.O.M.); (M.S.O.A.S.); (K.O.B.)
| | - Mohamed Ouldabdallahi Moukah
- Unité de Recherche Génomes et Milieux, Faculté des Sciences et Techniques, Université de Nouakchott, Nouakchott BP 880, Mauritania; (A.E.G.); (B.A.); (J.D.); (M.A.O.L.); (M.O.M.); (M.S.O.A.S.); (K.O.B.)
| | - Mohamed Salem Ould Ahmedou Salem
- Unité de Recherche Génomes et Milieux, Faculté des Sciences et Techniques, Université de Nouakchott, Nouakchott BP 880, Mauritania; (A.E.G.); (B.A.); (J.D.); (M.A.O.L.); (M.O.M.); (M.S.O.A.S.); (K.O.B.)
| | - Sébastien Briolant
- Unité de Parasitologie Entomologie, Département de Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées (IRBA), 13005 Marseille, France;
- Institut de Recherche pour le Développement (IRD), Assistance Publique-Hôpitaux de Marseille (AP-HM), Service de Santé des Armées (SSA), Vecteurs—Infections Tropicales et Méditerranéennes (VITROME), Aix Marseille Université, 13005 Marseille, France;
- Institut Hospitalo-Universitaire (IHU)-Méditerranée Infection, 13005 Marseille, France
| | - Leonardo K. Basco
- Institut de Recherche pour le Développement (IRD), Assistance Publique-Hôpitaux de Marseille (AP-HM), Service de Santé des Armées (SSA), Vecteurs—Infections Tropicales et Méditerranéennes (VITROME), Aix Marseille Université, 13005 Marseille, France;
- Institut Hospitalo-Universitaire (IHU)-Méditerranée Infection, 13005 Marseille, France
| | - Khyarhoum Ould Brahim
- Unité de Recherche Génomes et Milieux, Faculté des Sciences et Techniques, Université de Nouakchott, Nouakchott BP 880, Mauritania; (A.E.G.); (B.A.); (J.D.); (M.A.O.L.); (M.O.M.); (M.S.O.A.S.); (K.O.B.)
| | - Ali Ould Mohamed Salem Boukhary
- Unité de Recherche Génomes et Milieux, Faculté des Sciences et Techniques, Université de Nouakchott, Nouakchott BP 880, Mauritania; (A.E.G.); (B.A.); (J.D.); (M.A.O.L.); (M.O.M.); (M.S.O.A.S.); (K.O.B.)
- Institut de Recherche pour le Développement (IRD), Assistance Publique-Hôpitaux de Marseille (AP-HM), Service de Santé des Armées (SSA), Vecteurs—Infections Tropicales et Méditerranéennes (VITROME), Aix Marseille Université, 13005 Marseille, France;
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3
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Ganaie SS, Leung DW, Hartman AL, Amarasinghe GK. Host entry factors of Rift Valley Fever Virus infection. Adv Virus Res 2023; 117:121-136. [PMID: 37832991 DOI: 10.1016/bs.aivir.2023.09.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2023]
Abstract
Rift Valley Fever Virus (RVFV) is a negative sense segmented RNA virus that can cause severe hemorrhagic fever. The tri-segmented virus genome encodes for six (6) multifunctional proteins that engage host factors at a variety of different stages in the replication cycle. The S segment encodes nucleoprotein (N) and nonstructural protein S (NSs), the M segment encodes viral glycoproteins Gn and Gc as well as nonstructural protein M (NSm) and the L segment encodes the viral polymerase (L). Viral glycoproteins Gn and Gc are responsible for entry by binding to a number of host factors. Our recent studies identified a scavenger receptor, LDL receptor related protein 1 (Lrp1), as a potential pro-viral host factor for RVFV and related viruses, including Oropouche virus (OROV) infection. Coincidentally, several recent studies identified other LDL family proteins as viral entry factors and receptors for other viral families. Collectively, these observations suggest that highly conserved LDL family proteins may play a significant role in facilitating entry of viruses from several distinct families. Given the significant roles of viral and host factors during infection, characterization of these interactions is critical for therapeutic targeting with neutralizing antibodies and vaccines.
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Affiliation(s)
- Safder S Ganaie
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO, United States
| | - Daisy W Leung
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO, United States; Department of Medicine, Washington University School of Medicine, St Louis, MO, United States
| | - Amy L Hartman
- Center for Vaccine Research, University of Pittsburgh, Pittsburgh, PA, United States; Department of Infectious Diseases and Microbiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, United States
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO, United States.
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4
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Abdoullah B, Durand GA, Basco LK, El Bara A, Bollahi MA, Bosio L, Geulen M, Briolant S, Boukhary AOMS. Seroprevalence of Alphaviruses ( Togaviridae) among Urban Population in Nouakchott, Mauritania, West Africa. Viruses 2023; 15:1588. [PMID: 37515274 PMCID: PMC10385508 DOI: 10.3390/v15071588] [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: 06/22/2023] [Revised: 07/13/2023] [Accepted: 07/17/2023] [Indexed: 07/30/2023] Open
Abstract
The presence of alphaviruses, such as chikungunya virus (CHIKV), has never been reported in Mauritania. We assessed the seroprevalence of CHIKV among Nouakchott residents. A cross-sectional study involving 1300 non-febrile patients consulting at the Nouakchott hospital center was conducted between January and June 2021. The presence of anti-CHIKV IgG and neutralizing antibodies against CHIKV, O'nyong-nyong virus (ONNV), and Semliki Forest virus (SFV) was determined by an enzyme-linked immunosorbent assay (ELISA) and a serum neutralization test, respectively, and the associated risk factors were investigated. Of the 1300 study participants, serological evidence of previous exposure to CHIKV was observed in 37 individuals (2.8%). Sex, age, reported use of repellants, and bed net ownership and usage were not associated with CHIKV seropositivity. Our results showed the co-circulation of two other alphaviruses, ONNV and SFV, in Nouakchott in 30 (2.3%) individuals. This is the first study that documents the co-circulation of CHIKV, ONNV, and SFV in Mauritania, albeit at low prevalence. Surveillance and routine testing for alphaviruses and other arboviruses in symptomatic patients should be implemented in health facilities to assess the health burden associated with these viruses. Efforts should also be made to strengthen the vector control measures.
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Affiliation(s)
- Bedia Abdoullah
- Unité de Recherche Génomes et Milieux (GEMI), Université de Nouakchott, Nouveau Campus Universitaire, Nouakchott BP 5026, Mauritania
| | - Guillaume André Durand
- National Reference Center for Arboviruses, National Institute of Health and Medical Research (Inserm) and French Armed Forces Biomedical Research Institute (IRBA), 13005 Marseille, France
- Unité des Virus Émergents (UVE: Aix-Marseille Univ-IRD 190-Inserm 1207), 13005 Marseille, France
| | - Leonardo K Basco
- Aix Marseille Univ, IRD, AP-HM, SSA, VITROME, 13005 Marseille, France
- IHU-Méditerranée Infection, 13005 Marseille, France
| | - Ahmed El Bara
- Institut National de Recherche en Santé Publique, Nouakchott BP 695, Mauritania
| | | | - Laurent Bosio
- National Reference Center for Arboviruses, National Institute of Health and Medical Research (Inserm) and French Armed Forces Biomedical Research Institute (IRBA), 13005 Marseille, France
- Unité des Virus Émergents (UVE: Aix-Marseille Univ-IRD 190-Inserm 1207), 13005 Marseille, France
| | - Manon Geulen
- National Reference Center for Arboviruses, National Institute of Health and Medical Research (Inserm) and French Armed Forces Biomedical Research Institute (IRBA), 13005 Marseille, France
- Unité des Virus Émergents (UVE: Aix-Marseille Univ-IRD 190-Inserm 1207), 13005 Marseille, France
| | - Sébastien Briolant
- Aix Marseille Univ, IRD, AP-HM, SSA, VITROME, 13005 Marseille, France
- IHU-Méditerranée Infection, 13005 Marseille, France
- Unité de Parasitologie Entomologie, Département de Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées (IRBA), 13005 Marseille, France
| | - Ali Ould Mohamed Salem Boukhary
- Unité de Recherche Génomes et Milieux (GEMI), Université de Nouakchott, Nouveau Campus Universitaire, Nouakchott BP 5026, Mauritania
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Mohapatra RK, Kutikuppala LVS, Kandi V, Mishra S, Rabaan AA, Costa S, Al‐qaim ZH, Padhi BK, Sah R. Rift valley fever (RVF) viral zoonotic disease steadily circulates in the Mauritanian animals and humans: A narrative review. Health Sci Rep 2023; 6:e1384. [PMID: 37404448 PMCID: PMC10315559 DOI: 10.1002/hsr2.1384] [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: 01/19/2023] [Revised: 04/14/2023] [Accepted: 04/16/2023] [Indexed: 07/06/2023] Open
Abstract
Background and Aim Rift valley fever (RVF) virus (RVFV) is reportedly steadily circulating in Mauritania being repeated in 1987, 2010, 2012, 2015, and 2020. Mauritania seems a preferred niche for RVF virus due to its persistent outbreak there. Lately, nine Mauritanian wilayas confirmed 47 (23 fatalities with 49% CFR) human cases between August 30 and October 17, 2022. Most of the cases were largely among livestock breeders associated with animal husbandry activities. The review aimed at understanding the origin, cause, and measures to counter the virus. Methods The facts and figures from the various published articles sourced from databases including Pubmed, Web of Science, and the Scopus as also some primary data from health agencies like WHO, CDC, and so forth were evaluated and the efficacy of countermeasures reviewed. Results Among the reported confirmed cases, it was found that 3-70 year age-group males outnumbered the females. Deaths after fever occurred primarily due to acute hemorrhagic thrombocytopenia. Human infections often occurred through zoonotic transmission mainly through mosquitoes in the population contiguous to cattle outbreak, a conducive site for local RVFV transmission. Many transmission cases were through direct or indirect contact with blood or organs of the infected animal. Conclusion RVFV infection was predominant in the Mauritanian regions bordering Mali, Senegal, and Algeria. High human and domesticated animal density as also the existing zoonotic vectors further contributed to RVF virus circulation. Mauritanian RVF infection data confirmed that RVFV was zoonotic that included small ruminants, cattle, and camel. This observation hints at the role of transborder animal mobility in RVFV transmission. In light of this, preventive approaches with effective surveillance and monitoring system following the One Health model is extremely beneficial for a free and fair healthy world for all.
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Affiliation(s)
| | | | - Venkataramana Kandi
- Department of MicrobiologyPrathima Institute of Medical SciencesKarimnagarTelanganaIndia
| | - Snehasish Mishra
- School of Biotechnology, Campus‐11, KIIT Deemed‐to‐be‐UniversityBhubaneswarOdishaIndia
| | - Ali A. Rabaan
- Molecular Diagnostic Laboratory, Johns Hopkins Aramco HealthcareDhahranSaudi Arabia
- College of MedicineAlfaisal UniversityRiyadhSaudi Arabia
- Department of Public Health and NutritionThe University of HaripurHaripurPakistan
| | - Sharo Costa
- College of Osteopathic MedicineMichigan State UniversityEast LansingMichiganUSA
| | | | - Bijaya K. Padhi
- Department of Community MedicineSchool of Public Health, Postgraduate Institute of Medical Education and ResearchChandigarhIndia
| | - Ranjit Sah
- Institute of Medicine, Tribhuvan University Teaching HospitalKathmanduNepal
- Dr. D. Y. Patil Medical College, Hospital and Research Centre, Dr. D. Y. Patil VidyapeethPuneMaharashtraIndia
- Department of Public Health DentistryDr. D. Y. Patil Dental College and Hospital, Dr. D. Y. Patil VidyapeethPuneMaharashtraIndia
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Tabassum S, Naeem F, Azhar M, Naeem A, Oduoye MO, Dave T. Rift Valley fever virus outbreak in Mauritania yet again in 2022: No room for complacency. Health Sci Rep 2023; 6:e1278. [PMID: 37216056 PMCID: PMC10196093 DOI: 10.1002/hsr2.1278] [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: 03/15/2023] [Revised: 05/05/2023] [Accepted: 05/08/2023] [Indexed: 05/24/2023] Open
Abstract
Rift Valley fever is an important yet ignored viral hemorrhagic fever claiming many lives of African and Arabian countries over the past decade. Unfortunately, a recent outbreak of Rift Valley fever is currently ravaging in Mauritania. Death toll is rising continuously with 23 deaths reported in the month of October, 2022. Our article aims to shed light on the ongoing Rift Valley fever outbreak and recommendations to eradicate this potential threat to public health. Online databases including PubMed, the Lancet, and Science Direct as well as conferences, news, and press releases were used to for data collection. All the available medical literature related to Rift Valley fever in Mauritania were taken into consideration while writing the manuscript. As of October 17, 2022, 47 cases have been documented out of which 23 are dead. Case fatality rate has been reached to 49% which has given a wakeup call to the authorities. Efforts are being made by the concerned authorities and World Health Organization to halt the progression of this outbreak. Further investigations are required to completely eradicate the recurrent outbreaks in Mauritania especially in the area of vaccine development. Active involvement of public with the government authorities is of extreme significance in combating this disease.
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Affiliation(s)
- Shehroze Tabassum
- Department of Internal MedicineKing Edward Medical UniversityLahorePakistan
| | - Farhan Naeem
- Department of Internal MedicineKing Edward Medical UniversityLahorePakistan
| | - Masood Azhar
- Department of Internal MedicineKing Edward Medical UniversityLahorePakistan
| | - Aroma Naeem
- Department of Internal MedicineKing Edward Medical UniversityLahorePakistan
| | - Malik O. Oduoye
- College of Medical SciencesAhmadu Bello University Teaching Hospital (ABUTH)ShikaKaduna StateNigeria
| | - Tirth Dave
- Department of Internal MedicineBukovinian State Medical UniversityChernivtsiUkraine
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7
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Mechanistic models of Rift Valley fever virus transmission: A systematic review. PLoS Negl Trop Dis 2022; 16:e0010339. [PMID: 36399500 PMCID: PMC9718419 DOI: 10.1371/journal.pntd.0010339] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 12/02/2022] [Accepted: 10/31/2022] [Indexed: 11/19/2022] Open
Abstract
Rift Valley fever (RVF) is a zoonotic arbovirosis which has been reported across Africa including the northernmost edge, South West Indian Ocean islands, and the Arabian Peninsula. The virus is responsible for high abortion rates and mortality in young ruminants, with economic impacts in affected countries. To date, RVF epidemiological mechanisms are not fully understood, due to the multiplicity of implicated vertebrate hosts, vectors, and ecosystems. In this context, mathematical models are useful tools to develop our understanding of complex systems, and mechanistic models are particularly suited to data-scarce settings. Here, we performed a systematic review of mechanistic models studying RVF, to explore their diversity and their contribution to the understanding of this disease epidemiology. Researching Pubmed and Scopus databases (October 2021), we eventually selected 48 papers, presenting overall 49 different models with numerical application to RVF. We categorized models as theoretical, applied, or grey, depending on whether they represented a specific geographical context or not, and whether they relied on an extensive use of data. We discussed their contributions to the understanding of RVF epidemiology, and highlighted that theoretical and applied models are used differently yet meet common objectives. Through the examination of model features, we identified research questions left unexplored across scales, such as the role of animal mobility, as well as the relative contributions of host and vector species to transmission. Importantly, we noted a substantial lack of justification when choosing a functional form for the force of infection. Overall, we showed a great diversity in RVF models, leading to important progress in our comprehension of epidemiological mechanisms. To go further, data gaps must be filled, and modelers need to improve their code accessibility.
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8
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Seck I, Lo MM, Fall AG, Diop M, Ciss M, Cêtre-Sossah CB, Faye C, Lo M, Gaye AM, Coste C, Squarzoni-Diaw C, Alambedji RB, Sall B, Apolloni A, Lancelot R. Identification of drivers of Rift Valley fever after the 2013–14 outbreak in Senegal using serological data in small ruminants. PLoS Negl Trop Dis 2022; 16:e0010024. [PMID: 35108284 PMCID: PMC8843136 DOI: 10.1371/journal.pntd.0010024] [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: 02/17/2021] [Revised: 02/14/2022] [Accepted: 11/24/2021] [Indexed: 11/18/2022] Open
Abstract
Rift Valley fever (RVF) is a mosquito-borne disease mostly affecting wild and domestic ruminants. It is widespread in Africa, with spillovers in the Arab Peninsula and the southwestern Indian Ocean. Although RVF has been circulating in West Africa for more than 30 years, its epidemiology is still not clearly understood. In 2013, an RVF outbreak hit Senegal in new areas that weren’t ever affected before. To assess the extent of the spread of RVF virus, a national serological survey was implemented in young small ruminants (6–18 months old), between November 2014 and January 2015 (after the rainy season) in 139 villages. Additionally, the drivers of this spread were identified. For this purpose, we used a beta-binomial ( BB) logistic regression model. An Integrated Nested Laplace Approximation (INLA) approach was used to fit the spatial model. Lower cumulative rainfall, and higher accessibility were both associated with a higher RVFV seroprevalence. The spatial patterns of fitted RVFV seroprevalence pointed densely populated areas of western Senegal as being at higher risk of RVFV infection in small ruminants than rural or southeastern areas. Thus, because slaughtering infected animals and processing their fresh meat is an important RVFV transmission route for humans, more human populations might have been exposed to RVFV during the 2013–2014 outbreak than in previous outbreaks in Senegal. An outbreak of Rift Valley fever (RVF)–a zoonotic mosquito-borne viral infection widespread in Africa, was reported in 2013–14 in Senegal. After its end in late 2014, its spatial distribution and drivers were assessed using a national serological survey in small ruminants, thus highlighting the high exposition of humans to RVF virus in urban areas.
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Affiliation(s)
- Ismaila Seck
- Food and Agriculture Organization of the United Nations (FAO), Regional Office for Africa (RAF), Accra, Ghana
- Direction des Services vétérinaires (DSV), Dakar, Sénégal
- * E-mail:
| | - Modou Moustapha Lo
- Institut Sénégalais de Recherches Agricoles (ISRA), Laboratoire National de l’Élevage et de Recherches Vétérinaires (LNERV), Dakar-Hann, Sénégal
| | - Assane Gueye Fall
- Institut Sénégalais de Recherches Agricoles (ISRA), Laboratoire National de l’Élevage et de Recherches Vétérinaires (LNERV), Dakar-Hann, Sénégal
| | - Mariane Diop
- Institut Sénégalais de Recherches Agricoles (ISRA), Laboratoire National de l’Élevage et de Recherches Vétérinaires (LNERV), Dakar-Hann, Sénégal
| | - Mamadou Ciss
- Institut Sénégalais de Recherches Agricoles (ISRA), Laboratoire National de l’Élevage et de Recherches Vétérinaires (LNERV), Dakar-Hann, Sénégal
| | - Catherine Béatrice Cêtre-Sossah
- ASTRE, Univ. Montpellier, CIRAD, INRAE, Montpellier, France
- Centre de cooperation internationale en recherche agronomique pour le développement (CIRAD), UMR ASTRESainte Clotilde, la Réunion, France
| | - Coumba Faye
- Direction des Services vétérinaires (DSV), Dakar, Sénégal
| | - Mbargou Lo
- Direction des Services vétérinaires (DSV), Dakar, Sénégal
| | | | - Caroline Coste
- ASTRE, Univ. Montpellier, CIRAD, INRAE, Montpellier, France
- Centre de cooperation internationale en recherche agronomique pour le développement (CIRAD), UMR ASTRE, Montpellier, France
| | - Cécile Squarzoni-Diaw
- ASTRE, Univ. Montpellier, CIRAD, INRAE, Montpellier, France
- Centre de cooperation internationale en recherche agronomique pour le développement (CIRAD), UMR ASTRESainte Clotilde, la Réunion, France
| | | | - Baba Sall
- Direction des Services vétérinaires (DSV), Dakar, Sénégal
| | - Andrea Apolloni
- Institut Sénégalais de Recherches Agricoles (ISRA), Laboratoire National de l’Élevage et de Recherches Vétérinaires (LNERV), Dakar-Hann, Sénégal
- ASTRE, Univ. Montpellier, CIRAD, INRAE, Montpellier, France
- Centre de cooperation internationale en recherche agronomique pour le développement (CIRAD), UMR ASTRE, Montpellier, France
| | - Renaud Lancelot
- Centre de cooperation internationale en recherche agronomique pour le développement (CIRAD), UMR ASTRESainte Clotilde, la Réunion, France
- Centre de cooperation internationale en recherche agronomique pour le développement (CIRAD), UMR ASTRE, Montpellier, France
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Bob NS, Barry MA, Diagne MM, Faye M, Ndione MHD, Diallo A, Diop M, Diop B, Faye O, Loucoubar C, Fall G, Faye O. Detection of Rift Valley Fever Virus Lineage H from South Africa through Syndromic Sentinel Surveillance Network in Senegal. Open Forum Infect Dis 2021; 9:ofab655. [PMID: 35198642 PMCID: PMC8860161 DOI: 10.1093/ofid/ofab655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 12/27/2021] [Indexed: 11/23/2022] Open
Abstract
Background Rift Valley fever virus (RVFV) is an arbovirus that causes epizootics and epidemics among livestock population and humans. Our surveillance system has revealed multiple emergences and re-emergences of RVFV in West Africa over the last decade. Methods The Sentinel Syndromic Surveillance Network in Senegal (4S) has been implemented since 2011. Samples from human suspected arbovirus infection in 4S sentinel sites were sent to Institut Pasteur de Dakar (IPD), where arbovirus diagnosis by enzyme-linked immunosorbent assay (ELISA), real-time reverse transcription polymerase chain reaction (RT-PCR), and virus isolation was performed. Overall, IPD has received a total of 1149 samples from arboviral suspected patients through the 4S network from January to December 2020. These samples were screened for 7 arboviruses including RVFV. Whole-genome sequencing of positive RVFV samples by RT-PCR was performed using the Illumina Miseq platform followed by genome assembly. Phylogenetic analyses were performed using MEGA X. Results Out of the 1149 arbovirus suspected cases, 4 RVFV-positive samples were detected with RT-PCR while 5 RVFV-positive samples were detected by ELISA. Complete genome sequences were obtained for 3 strains among the 4 positive samples by RT-PCR. Phylogenetic analyses indicated an emergence of a virus first described in South Africa during a major outbreak. Conclusions This strong surveillance system allowed the detection of an RVFV outbreak in Senegal in 2020. The obtained genomes clustered with strains from South Africa belonging to lineage H. This calls for implementation of a strong surveillance system for wild animals, humans, and livestock simultaneously in all African countries.
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Affiliation(s)
| | | | | | - Martin Faye
- Pole of virology, Institut Pasteur of Dakar, Senegal
| | | | - Amadou Diallo
- Epidemiological unit, Institut Pasteur of Dakar,Senegal
| | - Mamadou Diop
- Epidemiological unit, Institut Pasteur of Dakar,Senegal
| | | | - Oumar Faye
- Pole of virology, Institut Pasteur of Dakar, Senegal
| | | | - Gamou Fall
- Pole of virology, Institut Pasteur of Dakar, Senegal
| | - Ousmane Faye
- Pole of virology, Institut Pasteur of Dakar, Senegal
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Tajudeen YA, Oladunjoye IO, Mustapha MO, Mustapha ST, Ajide-Bamigboye NT. Tackling the global health threat of arboviruses: An appraisal of the three holistic approaches to health. Health Promot Perspect 2021; 11:371-381. [PMID: 35079581 PMCID: PMC8767080 DOI: 10.34172/hpp.2021.48] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 09/03/2021] [Indexed: 12/20/2022] Open
Abstract
Background: The rapid circulation of arboviruses in the human population has been linked with changes in climatic, environmental, and socio-economic conditions. These changes are known to alter the transmission cycles of arboviruses involving the anthropophilic vectors and thus facilitate an extensive geographical distribution of medically important arboviral diseases, thereby posing a significant health threat. Using our current understanding and assessment of relevant literature, this review aimed to understand the underlying factors promoting the spread of arboviruses and how the three most renowned interdisciplinary and holistic approaches to health such as One Health, Eco-Health, and Planetary Health can be a panacea for control of arboviruses. Methods: A comprehensive structured search of relevant databases such as Medline, PubMed, WHO, Scopus, Science Direct, DOAJ, AJOL, and Google Scholar was conducted to identify recent articles on arboviruses and holistic approaches to health using the keywords including "arboviral diseases", "arbovirus vectors", "arboviral infections", "epidemiology of arboviruses", "holistic approaches", "One Health", "Eco-Health", and "Planetary Health". Results: Changes in climatic factors like temperature, humidity, and precipitation support the growth, breeding, and fecundity of arthropod vectors transmitting the arboviral diseases. Increased human migration and urbanization due to socio-economic factors play an important role in population increase leading to the rapid geographical distribution of arthropod vectors and transmission of arboviral diseases. Medical factors like misdiagnosis and misclassification also contribute to the spread of arboviruses. Conclusion: This review highlights two important findings: First, climatic, environmental, socio-economic, and medical factors influence the constant distributions of arthropod vectors. Second, either of the three holistic approaches or a combination of any two can be adopted on arboviral disease control. Our findings underline the need for holistic approaches as the best strategy to mitigating and controlling the emerging and reemerging arboviruses.
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11
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Coalson JE, Anderson EJ, Santos EM, Madera Garcia V, Romine JK, Luzingu JK, Dominguez B, Richard DM, Little AC, Hayden MH, Ernst KC. The Complex Epidemiological Relationship between Flooding Events and Human Outbreaks of Mosquito-Borne Diseases: A Scoping Review. ENVIRONMENTAL HEALTH PERSPECTIVES 2021; 129:96002. [PMID: 34582261 PMCID: PMC8478154 DOI: 10.1289/ehp8887] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 08/10/2021] [Accepted: 08/19/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Climate change is expected to increase the frequency of flooding events. Although rainfall is highly correlated with mosquito-borne diseases (MBD) in humans, less research focuses on understanding the impact of flooding events on disease incidence. This lack of research presents a significant gap in climate change-driven disease forecasting. OBJECTIVES We conducted a scoping review to assess the strength of evidence regarding the potential relationship between flooding and MBD and to determine knowledge gaps. METHODS PubMed, Embase, and Web of Science were searched through 31 December 2020 and supplemented with review of citations in relevant publications. Studies on rainfall were included only if the operationalization allowed for distinction of unusually heavy rainfall events. Data were abstracted by disease (dengue, malaria, or other) and stratified by post-event timing of disease assessment. Studies that conducted statistical testing were summarized in detail. RESULTS From 3,008 initial results, we included 131 relevant studies (dengue n = 45 , malaria n = 61 , other MBD n = 49 ). Dengue studies indicated short-term (< 1 month ) decreases and subsequent (1-4 month) increases in incidence. Malaria studies indicated post-event incidence increases, but the results were mixed, and the temporal pattern was less clear. Statistical evidence was limited for other MBD, though findings suggest that human outbreaks of Murray Valley encephalitis, Ross River virus, Barmah Forest virus, Rift Valley fever, and Japanese encephalitis may follow flooding. DISCUSSION Flooding is generally associated with increased incidence of MBD, potentially following a brief decrease in incidence for some diseases. Methodological inconsistencies significantly limit direct comparison and generalizability of study results. Regions with established MBD and weather surveillance should be leveraged to conduct multisite research to a) standardize the quantification of relevant flooding, b) study nonlinear relationships between rainfall and disease, c) report outcomes at multiple lag periods, and d) investigate interacting factors that modify the likelihood and severity of outbreaks across different settings. https://doi.org/10.1289/EHP8887.
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Affiliation(s)
- Jenna E. Coalson
- Center for Insect Science, University of Arizona, Tucson, Arizona, USA
| | | | - Ellen M. Santos
- Department of Epidemiology and Biostatistics, University of Arizona Mel and Enid Zuckerman College of Public Health, Tucson, Arizona, USA
| | - Valerie Madera Garcia
- Department of Epidemiology and Biostatistics, University of Arizona Mel and Enid Zuckerman College of Public Health, Tucson, Arizona, USA
| | - James K. Romine
- Department of Epidemiology and Biostatistics, University of Arizona Mel and Enid Zuckerman College of Public Health, Tucson, Arizona, USA
| | - Joy K. Luzingu
- Department of Epidemiology and Biostatistics, University of Arizona Mel and Enid Zuckerman College of Public Health, Tucson, Arizona, USA
| | - Brian Dominguez
- Department of Epidemiology and Biostatistics, University of Arizona Mel and Enid Zuckerman College of Public Health, Tucson, Arizona, USA
| | - Danielle M. Richard
- Department of Epidemiology and Biostatistics, University of Arizona Mel and Enid Zuckerman College of Public Health, Tucson, Arizona, USA
| | - Ashley C. Little
- Department of Epidemiology and Biostatistics, University of Arizona Mel and Enid Zuckerman College of Public Health, Tucson, Arizona, USA
| | - Mary H. Hayden
- National Institute for Human Resilience, University of Colorado Colorado Springs, Colorado Springs, Colorado, USA
| | - Kacey C. Ernst
- Department of Epidemiology and Biostatistics, University of Arizona Mel and Enid Zuckerman College of Public Health, Tucson, Arizona, USA
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12
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Filippitzi ME, Saegerman C. Quantitative Assessment of the Entry through Mechanical Transport in Aircraft of Rift Valley Fever Virus-Infected Mosquitoes into Previously Unaffected Areas. Pathogens 2021; 10:pathogens10050541. [PMID: 33946215 PMCID: PMC8145873 DOI: 10.3390/pathogens10050541] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/14/2021] [Accepted: 04/28/2021] [Indexed: 11/16/2022] Open
Abstract
(1): Rift Valley Fever (RVF) is a zoonotic disease of significant international health concern and considered as an emerging risk to Europe, where no RVF outbreaks in humans or animals have been reported so far. (2): Using a stochastic approach, we estimated the risk of RVF virus (RVFV) introduction during the period of May to October (the period when mosquito populations, including RVFV potential vectors, are present in European countries), into previously unaffected areas (e.g., United Kingdom, UK) via virus-carrying vectors traveling in commercial aircraft from RVF-affected countries (e.g., East Africa); (3): On average N = 68 (95% CI: 0-337), RVF-virus-infected mosquitoes are estimated to be mechanically transported by planes (with N = 0 as most likely), in direct flights from RVF-affected East African countries to the UK, between May and October. This estimate is considered as low but not negligible. The model developed should be easily scaled up to other European countries by amending appropriately country-specific variables (e.g., number of flights between countries) in order to map the areas/airports of higher risk and inform risk management per country accordingly and to adopt risk-mitigation measures.
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Affiliation(s)
- Maria-Eleni Filippitzi
- Veterinary Epidemiology Unit, Department of Epidemiology and Public Health, Sciensano, 1050 Brussels, Belgium
- Correspondence:
| | - Claude Saegerman
- Research Unit of Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR-ULiège), Fundamental and Applied Research for Animals and Health (FARAH) Center, Faculty of Veterinary Medicine, University of Liege, 4000 Liège, Belgium;
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Outammassine A, Zouhair S, Loqman S. Rift Valley Fever and West Nile virus vectors in Morocco: Current situation and future anticipated scenarios. Transbound Emerg Dis 2021; 69:1466-1478. [PMID: 33876581 DOI: 10.1111/tbed.14113] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 04/07/2021] [Accepted: 04/14/2021] [Indexed: 11/29/2022]
Abstract
Rift Valley Fever (RVF) and West Nile virus (WNV) are two important emerging Arboviruses transmitted by Aedes and Culex mosquitoes, typically Ae. caspius, Ae. detritus and Cx. pipiens in temperate regions. In Morocco, several outbreaks of WNV (1996, 2003 and 2010), affecting horses mostly, have been reported in north-western regions resulting in the death of 55 horses and one person cumulatively. Serological evidence of WNV local circulation, performed one year after the latest outbreak, revealed WNV neutralizing bodies in 59 out of 499 tested participants (El Rhaffouli et al., 2012). The country also shares common borders with northern Mauritania, where RVF is often documented. Human movement, livestock trade, climate changes and the availability of susceptible mosquito vectors are expected to increase the spread of these diseases in the country. Thus, in this study, we gathered a data set summarizing occurrences of Ae. caspius, Ae. detritus and Cx. pipiens in the country, and generated model prediction for their potential distribution under both current and future (2050) climate conditions, as a proxy to identify regions at-risk of RVF and WNV probable expansion. We found that the north-western regions (where the population is most concentrated), specifically along the Atlantic coastline, are highly suitable for Ae. caspius, Ae. detritus and Cx. pipiens, under present-day conditions. Future model scenarios anticipated possible range changes for the three mosquitoes under all climatic assumptions. All of the studied species are prospected to gain new areas that are currently not suitable, even under the most optimist scenario, thus placing additional human populations at risk. Our maps and predictions offer an opportunity to strategically target surveillance and control programmes. Public health officials, entomological surveillance and control delegation must augment efforts and continuously monitor these areas to reduce and minimize human infection risk.
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Affiliation(s)
- Abdelkrim Outammassine
- Laboratoire de Lutte contre les Maladies Infectieuses, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakech, Morocco
| | - Said Zouhair
- Laboratoire de Lutte contre les Maladies Infectieuses, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakech, Morocco.,Laboratory of Bacteriology-Virology, Avicienne Hospital Military, Marrakech, Morocco
| | - Souad Loqman
- Laboratoire de Lutte contre les Maladies Infectieuses, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakech, Morocco
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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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15
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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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16
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Cecilia H, Métras R, Fall AG, Lo MM, Lancelot R, Ezanno P. It's risky to wander in September: Modelling the epidemic potential of Rift Valley fever in a Sahelian setting. Epidemics 2020; 33:100409. [PMID: 33137548 DOI: 10.1016/j.epidem.2020.100409] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 08/27/2020] [Accepted: 09/16/2020] [Indexed: 11/15/2022] Open
Abstract
Estimating the epidemic potential of vector-borne diseases, along with the relative contribution of underlying mechanisms, is crucial for animal and human health worldwide. In West African Sahel, several outbreaks of Rift Valley fever (RVF) have occurred over the last decades, but uncertainty remains about the conditions necessary to trigger these outbreaks. We use the basic reproduction number (R0) as a measure of RVF epidemic potential in northern Senegal, and map its value in two distinct ecosystems, namely the Ferlo and the Senegal River delta and valley. We consider three consecutive rainy seasons (July-November 2014, 2015 and 2016) and account for several vector and animal species. We parametrize our model with estimates of Aedes vexans arabiensis, Culex poicilipes, Culex tritaeniorhynchus, cattle, sheep and goat abundances. The impact of RVF virus introduction is assessed every week over northern Senegal. We highlight September as the period of highest epidemic potential in northern Senegal, resulting from distinct dynamics in the two study areas. Spatially, in the seasonal environment of the Ferlo, we observe that high-risk locations vary between years. We show that decreased vector densities do not greatly reduce R0 and that cattle immunity has a greater impact on reducing transmission than small ruminant immunity. The host preferences of vectors and the temperature-dependent time interval between their blood meals are crucial parameters needing further biological investigations.
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Affiliation(s)
- Hélène Cecilia
- INRAE, Oniris, BIOEPAR, 44300, Nantes, France; UMR ASTRE, CIRAD, Montpellier, France; ASTRE, Montpellier University, CIRAD, INRAE, Montpellier, France.
| | - Raphaëlle Métras
- Inserm, Sorbonne Université, Institut Pierre Louis d'Epidémiologie et de Santé Publique (IPLESP), F-75012, Paris, France.
| | - Assane Gueye Fall
- Institut Sénégalais de Recherches Agricoles/Laboratoire National de l'Elevage et de Recherches Vétérinaires, BP 2057, Dakar-Hann, Senegal.
| | - Modou Moustapha Lo
- Institut Sénégalais de Recherches Agricoles/Laboratoire National de l'Elevage et de Recherches Vétérinaires, BP 2057, Dakar-Hann, Senegal.
| | - Renaud Lancelot
- UMR ASTRE, CIRAD, Montpellier, France; ASTRE, Montpellier University, CIRAD, INRAE, Montpellier, France.
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17
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Hardcastle AN, Osborne JCP, Ramshaw RE, Hulland EN, Morgan JD, Miller-Petrie MK, Hon J, Earl L, Rabinowitz P, Wasserheit JN, Gilbert M, Robinson TP, Wint GRW, Shirude S, Hay SI, Pigott DM. Informing Rift Valley Fever preparedness by mapping seasonally varying environmental suitability. Int J Infect Dis 2020; 99:362-372. [PMID: 32738486 PMCID: PMC7562817 DOI: 10.1016/j.ijid.2020.07.043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 07/09/2020] [Accepted: 07/24/2020] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Rift Valley Fever (RVF) poses a threat to human and animal health throughout much of Africa and the Middle East and has been recognized as a global health security priority and a key preparedness target. METHODS We combined RVF occurrence data from a systematic literature review with animal notification data from an online database. Using boosted regression trees, we made monthly environmental suitability predictions from January 1995 to December 2016 at a 5 × 5-km resolution throughout regions of Africa, Europe, and the Middle East. We calculated the average number of months per year suitable for transmission, the mean suitability for each calendar month, and the "spillover potential," a measure incorporating suitability with human and livestock populations. RESULTS Several countries where cases have not yet been reported are suitable for RVF. Areas across the region of interest are suitable for transmission at different times of the year, and some areas are suitable for multiple seasons each year. Spillover potential results show areas within countries where high populations of humans and livestock are at risk for much of the year. CONCLUSIONS The widespread environmental suitability of RVF highlights the need for increased preparedness, even in countries that have not previously experienced cases. These maps can aid in prioritizing long-term RVF preparedness activities and determining optimal times for recurring preparedness activities. Given an outbreak, our results can highlight areas often at risk for subsequent transmission that month, enabling decision-makers to target responses effectively.
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Affiliation(s)
- Austin N Hardcastle
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA
| | - Joshua C P Osborne
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA
| | - Rebecca E Ramshaw
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA
| | - Erin N Hulland
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA
| | - Julia D Morgan
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA
| | - Molly K Miller-Petrie
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA
| | - Julia Hon
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA
| | - Lucas Earl
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA
| | - Peter Rabinowitz
- Department of Global Health, University of Washington, Seattle, WA, USA
| | | | - Marius Gilbert
- Spatial Epidemiology Lab (SpELL), Université Libre de Bruxelles, Brussels, Belgium; Fonds National de la Recherche Scientifique (FNRS), Brussels, Belgium
| | - Timothy P Robinson
- Animal Production and Health Division (AGA), Food and Agriculture Organization of the United Nations, Italy
| | - G R William Wint
- Environmental Research Group Oxford (ERGO), c/o Department of Zoology, Oxford, UK
| | - Shreya Shirude
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA
| | - Simon I Hay
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA; Department of Health Metrics Sciences, School of Medicine, University of Washington, Seattle, WA, USA
| | - David M Pigott
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA; Department of Health Metrics Sciences, School of Medicine, University of Washington, Seattle, WA, USA.
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Rissmann M, Stoek F, Pickin MJ, Groschup MH. Mechanisms of inter-epidemic maintenance of Rift Valley fever phlebovirus. Antiviral Res 2019; 174:104692. [PMID: 31870761 DOI: 10.1016/j.antiviral.2019.104692] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 09/26/2019] [Accepted: 12/11/2019] [Indexed: 12/31/2022]
Abstract
Rift Valley fever phlebovirus (RVFV) is an arthropod-borne virus that has caused substantial epidemics throughout Africa and in the Arabian Peninsula. The virus can cause severe disease in livestock and humans and therefore the control and prevention of viral outbreaks is of utmost importance. The epidemiology of RVFV has some particular characteristics. Unexpected and significant epidemics have been observed in spatially and temporally divergent patterns across the African continent. Sudden epidemics in previously unaffected areas are followed by periods of long-term apparent absence of virus and sudden, unpredictable reoccurrence in disparate regions. Therefore, the elucidation of underlying mechanisms of viral maintenance is one of the largest gaps in the knowledge of RVFV ecology. It remains unknown whether the virus needs to be reintroduced before RVF outbreaks can occur, or if unperceived viral circulation in local vertebrates or mosquitoes is sufficient for maintenance of the virus. To gain insight into these knowledge gaps, we here review existing data that describe potential mechanisms of RVFV maintenance, as well as molecular and serological studies in endemic and non-endemic areas that provide evidence of an inter- or pre-epidemic virus presence. Basic and country-specific mechanisms of RVFV introduction into non-endemic countries are summarized and an overview of studies using mathematical modeling of RVFV persistence is given.
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Affiliation(s)
- Melanie Rissmann
- Friedrich-Loeffler-Institut, Institute of Novel and Emerging Infectious Diseases, Suedufer 10, 17489, Greifswald-Insel Riems, Germany
| | - Franziska Stoek
- Friedrich-Loeffler-Institut, Institute of Novel and Emerging Infectious Diseases, Suedufer 10, 17489, Greifswald-Insel Riems, Germany
| | - Matthew J Pickin
- Friedrich-Loeffler-Institut, Institute of Novel and Emerging Infectious Diseases, Suedufer 10, 17489, Greifswald-Insel Riems, Germany
| | - Martin H Groschup
- Friedrich-Loeffler-Institut, Institute of Novel and Emerging Infectious Diseases, Suedufer 10, 17489, Greifswald-Insel Riems, Germany.
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Ippoliti C, Candeloro L, Gilbert M, Goffredo M, Mancini G, Curci G, Falasca S, Tora S, Di Lorenzo A, Quaglia M, Conte A. Defining ecological regions in Italy based on a multivariate clustering approach: A first step towards a targeted vector borne disease surveillance. PLoS One 2019; 14:e0219072. [PMID: 31269045 PMCID: PMC6608978 DOI: 10.1371/journal.pone.0219072] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 06/14/2019] [Indexed: 01/21/2023] Open
Abstract
Ecoregionalization is the process by which a territory is classified in similar areas according to specific environmental and climatic factors. The climate and the environment strongly influence the presence and distribution of vectors responsible for significant human and animal diseases worldwide. In this paper, we developed a map of the eco-climatic regions of Italy adopting a data-driven spatial clustering approach using recent and detailed spatial data on climatic and environmental factors. We selected seven variables, relevant for a broad set of human and animal vector-borne diseases (VBDs): standard deviation of altitude, mean daytime land surface temperature, mean amplitude and peak timing of the annual cycle of land surface temperature, mean and amplitude of the annual cycle of greenness value, and daily mean amount of rainfall. Principal Component Analysis followed by multivariate geographic clustering using the k-medoids technique were used to group the pixels with similar characteristics into different ecoregions, and at different spatial resolutions (250 m, 1 km and 2 km). We showed that the spatial structure of ecoregions is generally maintained at different spatial resolutions and we compared the resulting ecoregion maps with two datasets related to Bluetongue vectors and West Nile Disease (WND) outbreaks in Italy. The known characteristics of Culicoides imicola habitat were well captured by 2/22 specific ecoregions (at 250 m resolution). Culicoides obsoletus/scoticus occupy all sampled ecoregions, according to its known widespread distribution across the peninsula. WND outbreak locations strongly cluster in 4/22 ecoregions, dominated by human influenced landscape, with intense cultivations and complex irrigation network. This approach could be a supportive tool in case of VBDs, defining pixel-based areas that are conducive environment for VBD spread, indicating where surveillance and prevention measures could be prioritized in Italy. Also, ecoregions suitable to specific VBDs vectors could inform entomological surveillance strategies.
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Affiliation(s)
- Carla Ippoliti
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise G. Caporale, Campo Boario, Teramo, Italy
| | - Luca Candeloro
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise G. Caporale, Campo Boario, Teramo, Italy
| | - Marius Gilbert
- Spatial Epidemiology Lab (SpELL), Université Libre de Bruxelles, Brussels, Belgium
| | - Maria Goffredo
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise G. Caporale, Campo Boario, Teramo, Italy
| | - Giuseppe Mancini
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise G. Caporale, Campo Boario, Teramo, Italy
| | - Gabriele Curci
- Department of Physical and Chemical Sciences, University of L’Aquila, L’Aquila, Italy
- Center of Excellence in Telesensing of Environment and Model Prediction of Severe Events (CETEMPS), University of L’Aquila, L’Aquila, Italy
| | - Serena Falasca
- Department of Physical and Chemical Sciences, University of L’Aquila, L’Aquila, Italy
- Center of Excellence in Telesensing of Environment and Model Prediction of Severe Events (CETEMPS), University of L’Aquila, L’Aquila, Italy
| | - Susanna Tora
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise G. Caporale, Campo Boario, Teramo, Italy
| | - Alessio Di Lorenzo
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise G. Caporale, Campo Boario, Teramo, Italy
| | - Michela Quaglia
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise G. Caporale, Campo Boario, Teramo, Italy
| | - Annamaria Conte
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise G. Caporale, Campo Boario, Teramo, Italy
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20
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Esser HJ, Mögling R, Cleton NB, van der Jeugd H, Sprong H, Stroo A, Koopmans MPG, de Boer WF, Reusken CBEM. Risk factors associated with sustained circulation of six zoonotic arboviruses: a systematic review for selection of surveillance sites in non-endemic areas. Parasit Vectors 2019; 12:265. [PMID: 31133059 PMCID: PMC6537422 DOI: 10.1186/s13071-019-3515-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 05/19/2019] [Indexed: 12/30/2022] Open
Abstract
Arboviruses represent a significant burden to public health and local economies due to their ability to cause unpredictable and widespread epidemics. To maximize early detection of arbovirus emergence in non-endemic areas, surveillance efforts should target areas where circulation is most likely. However, identifying such hotspots of potential emergence is a major challenge. The ecological conditions leading to arbovirus outbreaks are shaped by complex interactions between the virus, its vertebrate hosts, arthropod vector, and abiotic environment that are often poorly understood. Here, we systematically review the ecological risk factors associated with the circulation of six arboviruses that are of considerable concern to northwestern Europe. These include three mosquito-borne viruses (Japanese encephalitis virus, West Nile virus, Rift Valley fever virus) and three tick-borne viruses (Crimean-Congo hemorrhagic fever virus, tick-borne encephalitis virus, and louping-ill virus). We consider both intrinsic (e.g. vector and reservoir host competence) and extrinsic (e.g. temperature, precipitation, host densities, land use) risk factors, identify current knowledge gaps, and discuss future directions. Our systematic review provides baseline information for the identification of regions and habitats that have suitable ecological conditions for endemic circulation, and therefore may be used to target early warning surveillance programs aimed at detecting multi-virus and/or arbovirus emergence.
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Affiliation(s)
- Helen J Esser
- Resource Ecology Group, Wageningen University & Research, Wageningen, The Netherlands. .,Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands.
| | - Ramona Mögling
- Department of Viroscience, WHO CC for arbovirus and viral hemorrhagic fever reference and research, Erasmus University Medical Centre, Rotterdam, The Netherlands
| | - Natalie B Cleton
- Department of Viroscience, WHO CC for arbovirus and viral hemorrhagic fever reference and research, Erasmus University Medical Centre, Rotterdam, The Netherlands.,Centre for Infectious Disease Control, National Institute for Public Health and Environment (RIVM), Bilthoven, The Netherlands
| | - Henk van der Jeugd
- Vogeltrekstation-Dutch Centre for Avian Migration and Demography, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
| | - Hein Sprong
- Centre for Infectious Disease Control, National Institute for Public Health and Environment (RIVM), Bilthoven, The Netherlands
| | - Arjan Stroo
- Centre for Monitoring of Vectors (CMV), National Reference Centre (NRC), Netherlands Food and Consumer Product Safety Authority (NVWA), Ministry of Economic Affairs, Wageningen, The Netherlands
| | - Marion P G Koopmans
- Department of Viroscience, WHO CC for arbovirus and viral hemorrhagic fever reference and research, Erasmus University Medical Centre, Rotterdam, The Netherlands
| | - Willem F de Boer
- Resource Ecology Group, Wageningen University & Research, Wageningen, The Netherlands
| | - Chantal B E M Reusken
- Department of Viroscience, WHO CC for arbovirus and viral hemorrhagic fever reference and research, Erasmus University Medical Centre, Rotterdam, The Netherlands.,Centre for Infectious Disease Control, National Institute for Public Health and Environment (RIVM), Bilthoven, The Netherlands
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21
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Ndiaye EH, Diallo D, Fall G, Ba Y, Faye O, Dia I, Diallo M. Arboviruses isolated from the Barkedji mosquito-based surveillance system, 2012-2013. BMC Infect Dis 2018; 18:642. [PMID: 30541472 PMCID: PMC6292156 DOI: 10.1186/s12879-018-3538-2] [Citation(s) in RCA: 16] [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: 05/04/2018] [Accepted: 11/20/2018] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND A mosquito-based arbovirus surveillance system was set up at Barkedji, Senegal after the first outbreak of Rift valley fever in West Africa in 1988. This system was recently updated using more sampling methods and collecting in greater number of ponds and villages sites. METHODS For the current study, mosquitoes were sampled biweekly between July and December 2012 and 2013 using CDC+CO2 light traps set at ground and canopy level, mosquito nets baited with goat, sheep, human or chicken, light traps baited with goat, sheep and chicken; bird-baited traps using pigeons or chickens placed either at the ground or canopy level. Collected mosquitoes were identified, pooled and screened for arboviruses. RESULTS A total of 42,969 mosquitoes in 4,429 pools were processed for virus isolation. Ten virus species were identified among 103 virus isolates. West Nile virus (WNV; 31 isolates), Barkedji virus (BARV; 18), Sindbis virus (SINV; 13), Usutu virus (USUV; 12), Acado virus (ACAV; 8), Ndumu virus (NDUV; 9), Sanar virus (SANV; 7), Bagaza virus (BAGV; 3), Rift valley fever virus (RVFV; 1), and Yaounde virus (YAOV; 1) were isolated from 9 ponds (91 strains) and 7 villages (12 strains). Only 3 virus species (WNV, NDU and SINV) were isolated from villages. The largest numbers of isolates were collected in October (29.1% of total isolates) and November (50.5%). Viruses were isolated from 14 mosquito species including Cx. neavei (69.9% of the strains), Cx. antennatus (9.7%), and Ma. uniformis (4.8%). NDUV, ACAV, and SINV are herein reported for the first time in the Barkedji area. Isolation of ACAV and SANV from a pool of male Ma. uniformis and USUV and BARV from a pool of male Cx. neavei, are reported for the first time to our knowledge. CONCLUSION Our data indicate that the Barkedji area is characterized by a high diversity of viruses of medical, veterinary and unknown importance. Arboviruses were first detected in July at the beginning of the rainy season and peaked in abundance in October and November. The Barkedji area, an enzootic focus of several potentially emerging arboviruses, should be surveilled annually to be prepared to deal with future disease emergence events.
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Affiliation(s)
- El Hadji Ndiaye
- Unité d’Entomologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220 Dakar, Senegal
| | - Diawo Diallo
- Unité d’Entomologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220 Dakar, Senegal
| | - Gamou Fall
- Unité des Arbovirus et Virus de Fièvres Hémorragiques, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220 Dakar, Senegal
| | - Yamar Ba
- Unité d’Entomologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220 Dakar, Senegal
| | - Ousmane Faye
- Unité des Arbovirus et Virus de Fièvres Hémorragiques, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220 Dakar, Senegal
| | - Ibrahima Dia
- Unité d’Entomologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220 Dakar, Senegal
| | - Mawlouth Diallo
- Unité d’Entomologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220 Dakar, Senegal
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22
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Lo Iacono G, Cunningham AA, Bett B, Grace D, Redding DW, Wood JLN. Environmental limits of Rift Valley fever revealed using ecoepidemiological mechanistic models. Proc Natl Acad Sci U S A 2018; 115:E7448-E7456. [PMID: 30021855 PMCID: PMC6077718 DOI: 10.1073/pnas.1803264115] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Vector-borne diseases (VBDs) of humans and domestic animals are a significant component of the global burden of disease and a key driver of poverty. The transmission cycles of VBDs are often strongly mediated by the ecological requirements of the vectors, resulting in complex transmission dynamics, including intermittent epidemics and an unclear link between environmental conditions and disease persistence. An important broader concern is the extent to which theoretical models are reliable at forecasting VBDs; infection dynamics can be complex, and the resulting systems are highly unstable. Here, we examine these problems in detail using a case study of Rift Valley fever (RVF), a high-burden disease endemic to Africa. We develop an ecoepidemiological, compartmental, mathematical model coupled to the dynamics of ambient temperature and water availability and apply it to a realistic setting using empirical environmental data from Kenya. Importantly, we identify the range of seasonally varying ambient temperatures and water-body availability that leads to either the extinction of mosquito populations and/or RVF (nonpersistent regimens) or the establishment of long-term mosquito populations and consequently, the endemicity of the RVF infection (persistent regimens). Instabilities arise when the range of the environmental variables overlaps with the threshold of persistence. The model captures the intermittent nature of RVF occurrence, which is explained as low-level circulation under the threshold of detection, with intermittent emergence sometimes after long periods. Using the approach developed here opens up the ability to improve predictions of the emergence and behaviors of epidemics of many other important VBDs.
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Affiliation(s)
- Giovanni Lo Iacono
- Department of Veterinary Medicine, Disease Dynamics Unit, University of Cambridge, Cambridge CB3 0ES, United Kingdom;
- Public Health England, Didcot, Oxford OX11 0RQ, United Kingdom
- School of Veterinary Medicine, University of Surrey, Guildford GU2 7AL, United Kingdom
| | - Andrew A Cunningham
- Institute of Zoology, Zoological Society of London, London NW1 4RY, United Kingdom
| | - Bernard Bett
- Animal and Human Health Program, International Livestock Research Institute, Nairobi, 00100 Kenya
| | - Delia Grace
- Animal and Human Health Program, International Livestock Research Institute, Nairobi, 00100 Kenya
| | - David W Redding
- Centre for Biodiversity and Environment Research, Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
| | - James L N Wood
- Department of Veterinary Medicine, Disease Dynamics Unit, University of Cambridge, Cambridge CB3 0ES, United Kingdom
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23
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Mahmoud AS, Di Sabatino D, Danzetta ML, Iapaolo F, Tolari F, Forzan M, Mazzei M, Dayhum A, De Massis F, Monaco F. Rift Valley fever virus: a serological survey in Libyan ruminants. Open Vet J 2018; 8:204-207. [PMID: 30425953 PMCID: PMC6202668 DOI: 10.4314/ovj.v8i2.15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Accepted: 05/28/2018] [Indexed: 12/26/2022] Open
Abstract
A serological survey was carried out in Libya to investigate the circulation of Rift Valley fever virus (RVFV) among domestic ruminants. A total of 857 serum samples were collected from year 2015 to 2016 in eleven provinces of Libya belonging to five branches of the country. Samples were tested for RVFV antibodies using a competitive Enzyme-Linked Immunosorbent Assay (c-ELISA). Antibodies specific for RVFV were not detected in any of the 857 samples. However, a statistical analysis was carried out to assess the maximum expected number of infected animals and the maximum expected prevalence of RVFV among Libyan ruminants' populations according to the sampled population. The overall maximum expected prevalence was estimated to be 1.8% for cattle and 0.4% for small ruminants. Results seem to exclude the circulation of RVFV, however, a surveillance plan should be implemented in areas at risk of RVFV introduction.
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Affiliation(s)
- Abdusalam Sharef Mahmoud
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", (IZSAM), Teramo, Italy.,Department of Preventive Medicine, Faculty of Veterinary Medicine, University of Tripoli, Tripoli, Libya.,Department of Veterinary Science, University of Pisa, Pisa, Italy
| | - Daria Di Sabatino
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", (IZSAM), Teramo, Italy
| | - Maria Luisa Danzetta
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", (IZSAM), Teramo, Italy
| | - Federica Iapaolo
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", (IZSAM), Teramo, Italy
| | - Francesco Tolari
- Department of Veterinary Science, University of Pisa, Pisa, Italy
| | - Mario Forzan
- Department of Veterinary Science, University of Pisa, Pisa, Italy
| | - Maurizio Mazzei
- Department of Veterinary Science, University of Pisa, Pisa, Italy
| | - Abdunaser Dayhum
- Department of Preventive Medicine, Faculty of Veterinary Medicine, University of Tripoli, Tripoli, Libya.,National Center of Animal Health, Tripoli, Libya
| | - Fabrizio De Massis
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", (IZSAM), Teramo, Italy
| | - Federica Monaco
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", (IZSAM), Teramo, Italy
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24
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Ahmed A, Makame J, Robert F, Julius K, Mecky M. Sero-prevalence and spatial distribution of Rift Valley fever infection among agro-pastoral and pastoral communities during Interepidemic period in the Serengeti ecosystem, northern Tanzania. BMC Infect Dis 2018; 18:276. [PMID: 29898686 PMCID: PMC6001121 DOI: 10.1186/s12879-018-3183-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 06/03/2018] [Indexed: 11/30/2022] Open
Abstract
Background In the past two decades, Rift Valley Fever (RVF) outbreaks have been reported twice in Tanzania, with the most recent outbreak occurring in 2006/07. Given the ecology and climatic factors that support mosquito vectors in the Serengeti ecosystem, we hypothesized a continued transmission of RVF virus (RVFV) during interepidemic periods. This study was carried out to determine sero-prevalence, spatial distribution and factors associated with RVF in at-risk agro-pastoral and pastoral communities in the Serengeti Ecosystem in northern Tanzania. Methods A cross sectional study was carried out to establish the general exposure to RVFV by detecting anti–RVFV IgG and anti–RVFV IgM using ELISA techniques. The health facilities where human subjects were blood sampled concurrent with interviews included Bunda District Designated Hospital, Wasso DDH, Endulen hospital, Arash, Malambo, Olbabal, and Piyaya dispenaries (Ngorongoro district) and Nyerere DDH (Serengeti district) respectively. In addition, human subjects from Lamadi ward (Busega district) were recruited while receiving medical service at Bunda DDH. We conducted logistic regression to assess independent risk factor and mapped the hotspot areas for exposure to RVFV. Results A total of 751 subjects (males = 41.5%; females = 58.5%) with a median age of 35.5 years were enrolled at out-patient clinics. Of them, 34 (4.5, 95%CI 3.3–6.3%) tested positive for anti–RVFV IgG. Of the 34 that tested positive for anti–RVFV IgG, six (17.6%) tested positive for anti–RVFV IgM. Odds of exposure were higher among pastoral communities (aOR 2.9, 95% C.I: 1.21–6.89, p < 0.01), and agro-pastoral communities residing in Ngorongoro District (aOR 1.8, 95% C.I 1.14–3.39, p = 0.03). Hotspot areas for exposure to RVFV were Malambo, Olbalbal and Piyaya wards in Ngorongoro district, and Lamadi ward in Busega district. Conclusions The study found both previous and recent exposure of RVFV in humans residing in the Serengeti ecosystem as antibodies against both IgG and IgM were detected. Detection of anti-RVF IgM suggests an ongoing transmission of RVFV in humans during inter-epidemic periods. Residents of Ngorongoro district were most exposed to RVFV compared to Bunda and Serengeti districts. Therefore, the risk of exposure to RVFV was higher among pastoral communities compared to farming communities.
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Affiliation(s)
- Abade Ahmed
- Tanzania Field Epidemiology and Laboratory Training Program, Ministry of Health, Community Development, Gender, Elderly and Children, P.O Box 71286, Ocean Road, Dar es Salaam, Tanzania.
| | - Jabir Makame
- Tanzania Field Epidemiology and Laboratory Training Program, Ministry of Health, Community Development, Gender, Elderly and Children, P.O Box 71286, Ocean Road, Dar es Salaam, Tanzania.,Department of Microbiology and Immunology, Muhimbili University of Health and Allied Science, Dar es Salaam, Tanzania
| | | | - Keyyu Julius
- Tanzania Wildlife Research Institute, Arusha, Tanzania
| | - Matee Mecky
- Department of Microbiology and Immunology, Muhimbili University of Health and Allied Science, Dar es Salaam, Tanzania
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25
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Rift Valley fever in animals and humans: Current perspectives. Antiviral Res 2018; 156:29-37. [PMID: 29857007 DOI: 10.1016/j.antiviral.2018.05.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 05/21/2018] [Accepted: 05/24/2018] [Indexed: 02/03/2023]
Abstract
Rift Valley fever (RVF) is an ecologically complex emerging arboviral disease that causes significant illness in both livestock and people. This review article is designed to assist the reader in understanding the varied aspects of RVF disease in animals and humans. The historical facets of RVF disease, including the evolution of human outbreaks, are presented and discussed. The different clinical presentations of human RVF disease and the underlying causes are then addressed. We explore the exposure and transmission potential of RVF in animals and people. In the concluding section, we discuss the historical role of RVF as a biological weapon. We conclude with an outline of the important unanswered questions for ongoing research into this important zoonotic disease.
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26
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Kanouté YB, Gragnon BG, Schindler C, Bonfoh B, Schelling E. Reprint of "Epidemiology of brucellosis, Q Fever and Rift Valley Fever at the human and livestock interface in northern Côte d'Ivoire". Acta Trop 2017; 175:121-129. [PMID: 28867393 DOI: 10.1016/j.actatropica.2017.08.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Northern Côte d'Ivoire is the main livestock breeding zone and has the highest livestock cross-border movements in Côte d'Ivoire. The aim of this study was to provide updated epidemiological data on three neglected zoonotic diseases, namely brucellosis, Q Fever and Rift Valley Fever (RVF). We conducted three-stage cross-sectional cluster surveys in livestock and humans between 2012 and 2014 in a random selection of 63 villages and a sample of 633 cattle, 622 small ruminants and 88 people. We administered questionnaires to capture risk factors and performed serological tests including the Rose Bengal Plate Test (RBPT), Brucella spp. indirect and competitive ELISAs, Coxiella burnetii indirect ELISA and RVF competitive ELISA. The human seroprevalence for Brucella spp. was 5.3%. RBPT-positive small ruminants tested negative by the indirect ELISA. The seroprevalence of Brucella spp. in cattle adjusted for clustering was 4.6%. Cattle aged 5-8 years had higher odds of seropositivity (OR=3.5) than those aged ≤4years. The seropositivity in cattle was associated with having joint hygromas (OR=9), sharing the pastures with small ruminants (OR=5.8) and contact with pastoralist herds (OR=11.3). The seroprevalence of Q Fever was 13.9% in cattle, 9.4% in sheep and 12.4% in goats. The seroprevalence of RVF was 3.9% in cattle, 2.4% in sheep and 0% in goats. Seropositive ewes had greater odds (OR=4.7) of abortion than seronegative ones. In cattle, a shorter distance between the night pens and nearest permanent water bodies was a protective factor (OR=0.1). The study showed that the exposure to the three zoonoses is rather low in northern Côte d'Ivoire. Within a One Health approach, cost-benefit and cost-effectiveness of control measures should be assessed for an integrated control.
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Affiliation(s)
- Youssouf B Kanouté
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland.
| | - Biégo G Gragnon
- Laboratoire National d'Appui au Développement Agricole, Lanada, Korhogo, Côte d'Ivoire, Côte d'Ivoire
| | - Christian Schindler
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Bassirou Bonfoh
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire, Côte d'Ivoire
| | - Esther Schelling
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
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27
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Sallam MF, Fizer C, Pilant AN, Whung PY. Systematic Review: Land Cover, Meteorological, and Socioeconomic Determinants of Aedes Mosquito Habitat for Risk Mapping. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2017; 14:E1230. [PMID: 29035317 PMCID: PMC5664731 DOI: 10.3390/ijerph14101230] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 09/29/2017] [Accepted: 10/06/2017] [Indexed: 01/11/2023]
Abstract
Asian tiger and yellow fever mosquitoes (Aedes albopictus and Ae. aegypti) are global nuisances and are competent vectors for viruses such as Chikungunya (CHIKV), Dengue (DV), and Zika (ZIKV). This review aims to analyze available spatiotemporal distribution models of Aedes mosquitoes and their influential factors. A combination of five sets of 3-5 keywords were used to retrieve all relevant published models. Five electronic search databases were used: PubMed, MEDLINE, EMBASE, Scopus, and Google Scholar through 17 May 2017. We generated a hierarchical decision tree for article selection. We identified 21 relevant published studies that highlight different combinations of methodologies, models and influential factors. Only a few studies adopted a comprehensive approach highlighting the interaction between environmental, socioeconomic, meteorological and topographic systems. The selected articles showed inconsistent findings in terms of number and type of influential factors affecting the distribution of Aedes vectors, which is most likely attributed to: (i) limited availability of high-resolution data for physical variables, (ii) variation in sampling methods; Aedes feeding and oviposition behavior; (iii) data collinearity and statistical distribution of observed data. This review highlights the need and sets the stage for a rigorous multi-system modeling approach to improve our knowledge about Aedes presence/abundance within their flight range in response to the interaction between environmental, socioeconomic, and meteorological systems.
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Affiliation(s)
- Mohamed F Sallam
- Resilient Environment and Health, Agriculture and Water Solutions, National Exposure Research laboratory/System Exposure Division, Oak Ridge Institute for Science and Education, 109 T.W. Alexander Dr., Research Triangle Park, NC 27711, USA.
| | - Chelsea Fizer
- Oak Ridge Associated Universities, Contractor to US EPA, Office of Research and Development, National Exposure Research Laboratory, Environmental Protection Agency, 109 T.W. Alexander Drive, Research Triangle Park, NC 27711, USA.
| | - Andrew N Pilant
- Office of Research and Development, National Exposure Research Laboratory, Environmental Protection Agency, 109 T.W, Oak Ridge Associated Universities, Alexander Drive, Research Triangle Park, Oak Ridge, NC 27711, USA.
| | - Pai-Yei Whung
- Office of Research and Development, National Exposure Research Laboratory, Environmental Protection Agency, 109 T.W, Oak Ridge Associated Universities, Alexander Drive, Research Triangle Park, Oak Ridge, NC 27711, USA.
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28
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Métras R, Fournié G, Dommergues L, Camacho A, Cavalerie L, Mérot P, Keeling MJ, Cêtre-Sossah C, Cardinale E, Edmunds WJ. Drivers for Rift Valley fever emergence in Mayotte: A Bayesian modelling approach. PLoS Negl Trop Dis 2017; 11:e0005767. [PMID: 28732006 PMCID: PMC5540619 DOI: 10.1371/journal.pntd.0005767] [Citation(s) in RCA: 16] [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: 03/02/2017] [Revised: 08/02/2017] [Accepted: 06/30/2017] [Indexed: 11/28/2022] Open
Abstract
Rift Valley fever (RVF) is a major zoonotic and arboviral hemorrhagic fever. The conditions leading to RVF epidemics are still unclear, and the relative role of climatic and anthropogenic factors may vary between ecosystems. Here, we estimate the most likely scenario that led to RVF emergence on the island of Mayotte, following the 2006-2007 African epidemic. We developed the first mathematical model for RVF that accounts for climate, animal imports and livestock susceptibility, which is fitted to a 12-years dataset. RVF emergence was found to be triggered by the import of infectious animals, whilst transmissibility was approximated as a linear or exponential function of vegetation density. Model forecasts indicated a very low probability of virus endemicity in 2017, and therefore of re-emergence in a closed system (i.e. without import of infected animals). However, the very high proportion of naive animals reached in 2016 implies that the island remains vulnerable to the import of infectious animals. We recommend reinforcing surveillance in livestock, should RVF be reported is neighbouring territories. Our model should be tested elsewhere, with ecosystem-specific data.
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Affiliation(s)
- Raphaëlle Métras
- Centre for the Mathematical Modelling of Infectious Diseases, Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Guillaume Fournié
- Veterinary Epidemiology, Economics and Public Health group, Department of Pathobiology and Population Sciences, The Royal Veterinary College, Hatfield, United Kingdom
| | - Laure Dommergues
- GDS Mayotte-Coopérative Agricole des Eleveurs Mahorais, Coconi, Mayotte, France
| | - Anton Camacho
- Centre for the Mathematical Modelling of Infectious Diseases, Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Epicentre, Paris, France
| | - Lisa Cavalerie
- Centre de coopération internationale en recherche agronomique pour le développement (CIRAD) UMR ASTRE, Cyroi platform, Sainte Clotilde, La Réunion, France
- Institut National de Recherche Agronomique (INRA) UMR 1309 ASTRE, Montpellier, France
- Bureau de la Santé Animale, Direction Générale de l’Alimentation, Paris, France
- Université de La Réunion, Saint Denis, France
| | - Philippe Mérot
- Direction de l’Alimentation, de l’Agriculture et de la Forêt de Mayotte, Mamoudzou, France
| | - Matt J. Keeling
- WIDER, Warwick University, Coventry, United Kingdom
- Life Sciences, Warwick University, Coventry, United Kingdom
- Mathematics Institute, Warwick University, Coventry, United Kingdom
| | - Catherine Cêtre-Sossah
- Centre de coopération internationale en recherche agronomique pour le développement (CIRAD) UMR ASTRE, Cyroi platform, Sainte Clotilde, La Réunion, France
- Institut National de Recherche Agronomique (INRA) UMR 1309 ASTRE, Montpellier, France
| | - Eric Cardinale
- Centre de coopération internationale en recherche agronomique pour le développement (CIRAD) UMR ASTRE, Cyroi platform, Sainte Clotilde, La Réunion, France
- Institut National de Recherche Agronomique (INRA) UMR 1309 ASTRE, Montpellier, France
| | - W. John Edmunds
- Centre for the Mathematical Modelling of Infectious Diseases, Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
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Mint Mohamed Lemine A, Ould Lemrabott MA, Hasni Ebou M, Mint Lekweiry K, Ould Ahmedou Salem MS, Ould Brahim K, Ouldabdallahi Moukah M, Ould Bouraya IN, Brengues C, Trape JF, Basco L, Bogreau H, Simard F, Faye O, Ould Mohamed Salem Boukhary A. Mosquitoes (Diptera: Culicidae) in Mauritania: a review of their biodiversity, distribution and medical importance. Parasit Vectors 2017; 10:35. [PMID: 28103955 PMCID: PMC5248481 DOI: 10.1186/s13071-017-1978-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 01/10/2017] [Indexed: 11/30/2022] Open
Abstract
Although mosquitoes (Diptera: Culicidae) are important disease vectors, information on their biodiversity in Mauritania is scarce and very dispersed in the literature. Data from the scientific literature gathered in the country from 1948 to 2016 were collected and analyzed. Overall 51 culicid species comprising 17 Anopheles spp., 14 Aedes spp., 18 Culex spp. and two Mansonia spp. have been described in Mauritania among which Anopheles arabiensis, Aedes vexans, Culex poicilipes and Culex antennatus are of epidemiological significance. Anopheles arabiensis is widely distributed throughout the country and its geographic distribution has increased northwards in recent years, shifting its northern limit form 17°32′N in the 1960s to 18°47′N today. Its presence in the central region of Tagant highlights the great ecological plasticity of the species. Conversely, the distribution of Anopheles gambiae (s.s.) and Anopheles melas has shrunk compared to that of the 1960s. Anopheles rhodesiensis and An. d’thali are mainly confined in the mountainous areas (alt. 200–700 m), whereas Anopheles pharoensis is widely distributed in the Senegal River basin. Culex poicilipes and Cx. antenattus were naturally found infected with Rift valley fever virus in central and northern Mauritania following the Rift valley outbreaks of 1998 and 2012. Recently, Ae. aegypti emerged in Nouakchott and is probably responsible for dengue fever episodes of 2015. This paper provides a concise and up-to-date overview of the existing literature on mosquito species known to occur in Mauritania and highlights areas where future studies should fill a gap in knowledge about vector biodiversity. It aims to help ongoing and future research on mosquitoes particularly in the field of medical entomology to inform evidence-based decision-making for vector control and management strategies.
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Affiliation(s)
- Aichetou Mint Mohamed Lemine
- Unité de recherche Génomes et Milieux, Jeune Equipe Associée à l'IRD (RI3M), Université de Nouakchott Al-Aasriya, Faculté des Sciences et Techniques, Nouveau Campus Universitaire, Nouakchott, BP 5026, Mauritania.,Laboratoire d'Ecologie Vectorielle et Parasitaire, Faculté des Sciences et Techniques, Université Cheikh Anta Diop, Dakar, Senegal
| | - Mohamed Aly Ould Lemrabott
- Unité de recherche Génomes et Milieux, Jeune Equipe Associée à l'IRD (RI3M), Université de Nouakchott Al-Aasriya, Faculté des Sciences et Techniques, Nouveau Campus Universitaire, Nouakchott, BP 5026, Mauritania
| | - Moina Hasni Ebou
- Unité de recherche Génomes et Milieux, Jeune Equipe Associée à l'IRD (RI3M), Université de Nouakchott Al-Aasriya, Faculté des Sciences et Techniques, Nouveau Campus Universitaire, Nouakchott, BP 5026, Mauritania
| | - Khadijetou Mint Lekweiry
- Unité de recherche Génomes et Milieux, Jeune Equipe Associée à l'IRD (RI3M), Université de Nouakchott Al-Aasriya, Faculté des Sciences et Techniques, Nouveau Campus Universitaire, Nouakchott, BP 5026, Mauritania
| | - Mohamed Salem Ould Ahmedou Salem
- Unité de recherche Génomes et Milieux, Jeune Equipe Associée à l'IRD (RI3M), Université de Nouakchott Al-Aasriya, Faculté des Sciences et Techniques, Nouveau Campus Universitaire, Nouakchott, BP 5026, Mauritania
| | - Khyarhoum Ould Brahim
- Unité de recherche Génomes et Milieux, Jeune Equipe Associée à l'IRD (RI3M), Université de Nouakchott Al-Aasriya, Faculté des Sciences et Techniques, Nouveau Campus Universitaire, Nouakchott, BP 5026, Mauritania
| | - Mohamed Ouldabdallahi Moukah
- Unité de recherche Génomes et Milieux, Jeune Equipe Associée à l'IRD (RI3M), Université de Nouakchott Al-Aasriya, Faculté des Sciences et Techniques, Nouveau Campus Universitaire, Nouakchott, BP 5026, Mauritania
| | | | - Cecile Brengues
- Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Unité Mixte de Recherche IRD224-CNRS5290-Université de Montpellier, Institut de Recherche pour le Développement (IRD), Montpellier, France
| | - Jean-François Trape
- Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Unité Mixte de Recherche IRD224-CNRS5290-Université de Montpellier, Institut de Recherche pour le Développement (IRD), Montpellier, France
| | - Leonardo Basco
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes (URMITE), UM 63, CNRS 7278, IRD 198, Inserm 1095, Faculté de Médecine La Timone, Aix-Marseille Université, Marseille, 13385, France
| | - Hervé Bogreau
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes (URMITE), UM 63, CNRS 7278, IRD 198, Inserm 1095, Faculté de Médecine La Timone, Aix-Marseille Université, Marseille, 13385, France.,Unité Parasitologie et Entomologie, Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France
| | - Frédéric Simard
- Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Unité Mixte de Recherche IRD224-CNRS5290-Université de Montpellier, Institut de Recherche pour le Développement (IRD), Montpellier, France
| | - Ousmane Faye
- Laboratoire d'Ecologie Vectorielle et Parasitaire, Faculté des Sciences et Techniques, Université Cheikh Anta Diop, Dakar, Senegal
| | - Ali Ould Mohamed Salem Boukhary
- Unité de recherche Génomes et Milieux, Jeune Equipe Associée à l'IRD (RI3M), Université de Nouakchott Al-Aasriya, Faculté des Sciences et Techniques, Nouveau Campus Universitaire, Nouakchott, BP 5026, Mauritania.
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30
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Samy AM, Peterson AT, Hall M. Phylogeography of Rift Valley Fever Virus in Africa and the Arabian Peninsula. PLoS Negl Trop Dis 2017; 11:e0005226. [PMID: 28068340 PMCID: PMC5221768 DOI: 10.1371/journal.pntd.0005226] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 12/01/2016] [Indexed: 01/31/2023] Open
Abstract
Rift Valley Fever is an acute zoonotic viral disease caused by Rift Valley Fever virus (RVFV) that affects ruminants and humans in Sub-Saharan Africa and the Arabian Peninsula. We used phylogenetic analyses to understand the demographic history of RVFV populations, using sequence data from the three minigenomic segments of the virus. We used phylogeographic approaches to infer RVFV historical movement patterns across its geographic range, and to reconstruct transitions among host species. Results revealed broad circulation of the virus in East Africa, with many lineages originating in Kenya. Arrival of RVFV in Madagascar resulted from three major waves of virus introduction: the first from Zimbabwe, and the second and third from Kenya. The two major outbreaks in Egypt since 1977 possibly resulted from a long-distance introduction from Zimbabwe during the 1970s, and a single introduction took RVFV from Kenya to Saudi Arabia. Movement of the virus between Kenya and Sudan, and CAR and Zimbabwe, was in both directions. Viral populations in West Africa appear to have resulted from a single introduction from Central African Republic. The overall picture of RVFV history is thus one of considerable mobility, and dynamic evolution and biogeography, emphasizing its invasive potential, potentially more broadly than its current distributional limits. Rift Valley Fever is an acute zoonotic viral disease caused by Rift Valley Fever virus (RVFV) that affects ruminants and humans in Sub-Saharan Africa and the Arabian Peninsula. We used phylogenetic approaches that take sampling date into account to understand the demographic history of RVFV populations, using sequence data from the three minigenomic segments of the virus. We found evidence of broad circulation of the virus in East Africa, with many lineages originating in Kenya, with single and multiple introductions of RVFV among countries. The overall picture of RVFV history is thus one of considerable mobility, and dynamic evolution and biogeography, emphasizing its invasive potential, potentially more broadly than its current distributional limits.
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Affiliation(s)
- Abdallah M. Samy
- Biodiversity Institute, University of Kansas, Lawrence, Kansas, United States of America
- Entomology Department, Faculty of Science, Ain Shams University, Abbassia, Cairo, Egypt
- * E-mail: ,
| | - A. Townsend Peterson
- Biodiversity Institute, University of Kansas, Lawrence, Kansas, United States of America
| | - Matthew Hall
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Immunity, Infection and Evolution, University of Edinburgh, Edinburgh, United Kingdom
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
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31
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Kanouté YB, Gragnon BG, Schindler C, Bonfoh B, Schelling E. Epidemiology of brucellosis, Q Fever and Rift Valley Fever at the human and livestock interface in northern Côte d'Ivoire. Acta Trop 2017; 165:66-75. [PMID: 26899680 DOI: 10.1016/j.actatropica.2016.02.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 02/10/2016] [Accepted: 02/14/2016] [Indexed: 12/26/2022]
Abstract
Northern Côte d'Ivoire is the main livestock breeding zone and has the highest livestock cross-border movements in Côte d'Ivoire. The aim of this study was to provide updated epidemiological data on three neglected zoonotic diseases, namely brucellosis, Q Fever and Rift Valley Fever (RVF). We conducted three-stage cross-sectional cluster surveys in livestock and humans between 2012 and 2014 in a random selection of 63 villages and a sample of 633 cattle, 622 small ruminants and 88 people. We administered questionnaires to capture risk factors and performed serological tests including the Rose Bengal Plate Test (RBPT), Brucella spp. indirect and competitive ELISAs, Coxiella burnetii indirect ELISA and RVF competitive ELISA. The human seroprevalence for Brucella spp. was 5.3%. RBPT-positive small ruminants tested negative by the indirect ELISA. The seroprevalence of Brucella spp. in cattle adjusted for clustering was 4.6%. Cattle aged 5-8 years had higher odds of seropositivity (OR=3.5) than those aged ≤4years. The seropositivity in cattle was associated with having joint hygromas (OR=9), sharing the pastures with small ruminants (OR=5.8) and contact with pastoralist herds (OR=11.3). The seroprevalence of Q Fever was 13.9% in cattle, 9.4% in sheep and 12.4% in goats. The seroprevalence of RVF was 3.9% in cattle, 2.4% in sheep and 0% in goats. Seropositive ewes had greater odds (OR=4.7) of abortion than seronegative ones. In cattle, a shorter distance between the night pens and nearest permanent water bodies was a protective factor (OR=0.1). The study showed that the exposure to the three zoonoses is rather low in northern Côte d'Ivoire. Within a One Health approach, cost-benefit and cost-effectiveness of control measures should be assessed for an integrated control.
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Affiliation(s)
- Youssouf B Kanouté
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland.
| | - Biégo G Gragnon
- Laboratoire National d'Appui au Développement Agricole, Lanada, Korhogo, Côte d'Ivoire, Côte d'Ivoire
| | - Christian Schindler
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Bassirou Bonfoh
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire, Côte d'Ivoire
| | - Esther Schelling
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
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32
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Serological and genomic evidence of Rift Valley fever virus during inter-epidemic periods in Mauritania. Epidemiol Infect 2016; 145:1058-1068. [PMID: 28029091 DOI: 10.1017/s0950268816003022] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Rift Valley fever virus (RVFV) is an emerging pathogen of major concern throughout Africa and the Arabian Peninsula, affecting both livestock and humans. In the past recurrent epidemics were reported in Mauritania and studies focused on the analysis of samples from affected populations during acute outbreaks. To verify characteristics and presence of RVFV during non-epidemic periods we implemented a multi-stage serological and molecular analysis. Serum samples of small ruminants, cattle and camels were obtained from Mauritania during an inter-epidemic period in 2012-2013. This paper presents a comparative analysis of potential variations and shifts of antibody presence and the capability of inter-epidemic infections in Mauritanian livestock. We observed distinct serological differences between tested species (seroprevalence: small ruminants 3·8%, cattle 15·4%, camels 32·0%). In one single bovine from Nouakchott, a recent RVF infection could be identified by the simultaneous detection of IgM antibodies and viral RNA. This study indicates the occurrence of a low-level enzootic RVFV circulation in livestock in Mauritania. Moreover, results indicate that small ruminants can preferably act as sentinels for RVF surveillance.
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33
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Baba M, Masiga DK, Sang R, Villinger J. Has Rift Valley fever virus evolved with increasing severity in human populations in East Africa? Emerg Microbes Infect 2016; 5:e58. [PMID: 27329846 PMCID: PMC4932650 DOI: 10.1038/emi.2016.57] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 03/08/2016] [Accepted: 03/16/2016] [Indexed: 11/19/2022]
Abstract
Rift Valley fever (RVF) outbreaks have occurred across eastern Africa from 1912 to 2010 approximately every 4–15 years, most of which have not been accompanied by significant epidemics in human populations. However, human epidemics during RVF outbreaks in eastern Africa have involved 478 deaths in 1998, 1107 reported cases with 350 deaths from 2006 to 2007 and 1174 cases with 241 deaths in 2008. We review the history of RVF outbreaks in eastern Africa to identify the epidemiological factors that could have influenced its increasing severity in humans. Diverse ecological factors influence outbreak frequency, whereas virus evolution has a greater impact on its virulence in hosts. Several factors could have influenced the lack of information on RVF in humans during earlier outbreaks, but the explosive nature of human RVF epidemics in recent years mirrors the evolutionary trend of the virus. Comparisons between isolates from different outbreaks have revealed an accumulation of genetic mutations and genomic reassortments that have diversified RVF virus genomes over several decades. The threat to humans posed by the diversified RVF virus strains increases the potential public health and socioeconomic impacts of future outbreaks. Understanding the shifting RVF epidemiology as determined by its evolution is key to developing new strategies for outbreak mitigation and prevention of future human RVF casualties.
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Affiliation(s)
- Marycelin Baba
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi 00100, Kenya.,Department of Medical Laboratory Science, PMB 1069, University of Maiduguri, Maiduguri 600230, Nigeria
| | - Daniel K Masiga
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi 00100, Kenya
| | - Rosemary Sang
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi 00100, Kenya
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi 00100, Kenya
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34
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Salem MLO, Baba SEWO, Fall-Malick FZ, Boushab BM, Ghaber SM, Mokhtar A. [Severe hemorrhagic forms of Rift Valley fever: about 5 cases]. Pan Afr Med J 2016; 24:73. [PMID: 27642413 PMCID: PMC5012792 DOI: 10.11604/pamj.2016.24.73.9573] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 05/02/2016] [Indexed: 11/23/2022] Open
Abstract
La fièvre de la vallée du Rift (FVR) est une arbovirose due à un virus à ARN appartenant à la famille de Bunyaviridae (genre phlebovirus). C'est une zoonose touchant principalement les animaux mais pouvant aussi contaminer l'homme, soit directement par la manipulation des viandes ou avortons d'animaux malades ou indirectement par la piqure de moustiques infectées (Aèdes sp, anophèles sp, Culex sp). Dans la majorité des cas, l'infection humaine à FVR est asymptomatique, mais elle peut également se manifester par un syndrome fébrile modérée d’évolution favorable. Néanmoins, certains patients peuvent développer un syndrome hémorragique et/ou des lésions neurologiques d’évolution mortelle. Nous décrivons l’évolution de cinq cas de patients atteints de la FVR, admis dans le service de médecine interne du Centre Hospitalier National de Nouakchott (Mauritanie), le mois d'Octobre 2015 et présentant tous, un syndrome hémorragique dans un contexte fébrile. L’évolution n’était favorable que pour 2 des cinq patients. Les 3 autres sont décédés, deux dans un tableau de choc hémorragique et dans un état de choc septique.
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Affiliation(s)
- Mohamed Lemine Ould Salem
- Service des Laboratoires, Centre Hospitalier National de Nouakchott, Mauritanie; Faculté de Médecine de Nouakchott, Mauritanie
| | - Sidi El Wafi Ould Baba
- Faculté de Médecine de Nouakchott, Mauritanie; Service de Médecine interne, Centre Hospitalier National de Nouakchott, Mauritanie
| | - Fatimetou Zahra Fall-Malick
- Faculté de Médecine de Nouakchott, Mauritanie; Institut National d'Hépato-virologie de Nouakchott, Mauritanie
| | | | | | - Abdelwedoud Mokhtar
- Service de Médecine interne, Centre Hospitalier National de Nouakchott, Mauritanie
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35
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Nanyingi MO, Munyua P, Kiama SG, Muchemi GM, Thumbi SM, Bitek AO, Bett B, Muriithi RM, Njenga MK. A systematic review of Rift Valley Fever epidemiology 1931-2014. Infect Ecol Epidemiol 2015; 5:28024. [PMID: 26234531 PMCID: PMC4522434 DOI: 10.3402/iee.v5.28024] [Citation(s) in RCA: 124] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 06/15/2015] [Accepted: 07/10/2015] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Rift Valley Fever (RVF) is a mosquito-borne viral zoonosis that was first isolated and characterized in 1931 in Kenya. RVF outbreaks have resulted in significant losses through human illness and deaths, high livestock abortions and deaths. This report provides an overview on epidemiology of RVF including ecology, molecular diversity spatiotemporal analysis, and predictive risk modeling. METHODOLOGY Using the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, we systematically searched for relevant RVF publications in repositories of the World Health Organization Library and Information Networks for Knowledge (WHOLIS), U.S Centers for Disease Control and Prevention (CDC), and Food and Agricultural Organization (FAO). Detailed searches were performed in Google Scholar, SpringerLink, and PubMed databases and included conference proceedings and books published from 1931 up to 31st January 2015. RESULTS AND DISCUSSION A total of 84 studies were included in this review; majority (50%) reported on common human and animal risk factors that included consumption of animal products, contact with infected animals and residing in low altitude areas associated with favorable climatic and ecological conditions for vector emergence. A total of 14 (16%) of the publications described RVF progressive spatial and temporal distribution and the use of risk modeling for timely prediction of imminent outbreaks. Using distribution maps, we illustrated the gradual spread and geographical extent of disease; we also estimated the disease burden using aggregate human mortalities and cumulative outbreak periods for endemic regions. CONCLUSION This review outlines common risk factors for RVF infections over wider geographical areas; it also emphasizes the role of spatial models in predicting RVF enzootics. It, therefore, explains RVF epidemiological status that may be used for design of targeted surveillance and control programs in endemic countries.
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Affiliation(s)
- Mark O Nanyingi
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
- Department of Public Health, Pharmacology and Toxicology, University of Nairobi, Nairobi, Kenya
- Kenya Medical Research Institute, Nairobi, Kenya;
| | - Peninah Munyua
- Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Stephen G Kiama
- Wangari Maathai Institute for Peace and Environmental Studies, University of Nairobi, Nairobi, Kenya
| | - Gerald M Muchemi
- Department of Public Health, Pharmacology and Toxicology, University of Nairobi, Nairobi, Kenya
| | - Samuel M Thumbi
- Kenya Medical Research Institute, Nairobi, Kenya
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, USA
| | - Austine O Bitek
- Zoonotic Disease Unit, Nairobi, Kenya
- Directorate of Veterinary Service, Nairobi, Kenya
| | - Bernard Bett
- International Livestock Research Institute, Nairobi, Kenya
| | | | - M Kariuki Njenga
- Kenya Medical Research Institute, Nairobi, Kenya
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, USA
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36
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Lo MM, Mbao V, Sierra P, Thiongane Y, Diop M, Donadeu M, Dungu B. Safety and immunogenicity of Onderstepoort Biological Products' Rift Valley fever Clone 13 vaccine in sheep and goats under field conditions in Senegal. ACTA ACUST UNITED AC 2015; 82:857. [PMID: 26244679 PMCID: PMC6238691 DOI: 10.4102/ojvr.v82i1.857] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Revised: 01/06/2015] [Accepted: 01/07/2015] [Indexed: 11/29/2022]
Abstract
This blinded field safety study was conducted in Senegal to assess safety and immunogenicity of administration of the registered dose of Rift Valley fever virus (RVFV) Clone 13 vaccine (Onderstepoort Biological Products) to sheep and goats of West African breeds under natural conditions. A total of 267 small ruminants (220 sheep, 47 goats) were included; half received RVFV Clone 13 vaccine at the recommended dose and half received the diluent (as placebo) only. The study was performed on three commercial farms in the northern and eastern region of Senegal in accordance with veterinary good clinical practices. The animals were observed daily for 3 days after vaccination, and then weekly for 1 year. In both sheep and goats vaccinated against RVFV seroconversion rates above 70% were recorded. No seroconversion related to RVFV was observed in placebo-treated animals. No statistically significant differences were determined between placebo and vaccinated groups for mean rectal temperatures for the first 3 days after administration (p > 0.05). No abnormal clinical signs related to treatment were noted, and only one slight injection site reaction was observed in one vaccinated animal for 2 days after vaccination. Out of 176 births assessed over 1 year (93 from the vaccinated group, 83 from the placebo group), 9 were abnormal in the placebo group and 3 in the vaccinated group (p > 0.05). The frequency of adverse events was similar in the placebo and vaccinated groups. RVFV Clone 13 vaccine administered according to the manufacturer's instructions was safe and well tolerated in West African breeds of sheep and goats, including animals of approximately 6 months of age and pregnant females, under field conditions in Senegal. Antibody levels persisted up to 1 year after vaccination.
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Affiliation(s)
| | - Victor Mbao
- Global Alliance for Livestock Veterinary Medicines.
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37
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Arsevska E, Hellal J, Mejri S, Hammami S, Marianneau P, Calavas D, Hénaux V. Identifying Areas Suitable for the Occurrence of Rift Valley Fever in North Africa: Implications for Surveillance. Transbound Emerg Dis 2015; 63:658-674. [PMID: 25655790 DOI: 10.1111/tbed.12331] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Indexed: 12/01/2022]
Abstract
Rift Valley fever (RVF) is a vector-borne zoonotic disease that has caused widespread outbreaks throughout Africa and the Arabian Peninsula, with serious consequences for livestock-based economies and public health. Although there have never been any reports of RVF in Morocco, Algeria, Tunisia and Libya, it is a priority disease in the Maghreb, due to the threat of introduction of the virus through transboundary livestock movements or infected mosquito vectors. However, the implementation of surveillance activities and early warning contingency plans requires better knowledge of the epidemiological situation. We conducted a multicriteria decision analysis, integrating host distribution with a combination of important ecological factors that drive mosquito abundance, to identify hotspots and suitable time periods for RVF enzootic circulation (i.e. stable transmission at a low to moderate level for an extended period of time) and an RVF epizootic event (i.e. a sudden occurrence of a large number of infected animals over a large geographic area) in the Maghreb. We also modelled vector species distribution using available information on vector presence and habitat preference. We found that the northern regions of the Maghreb were moderately suitable for RVF enzootics, but highly suitable for RVF epizootics. The vector species distribution model identified these regions as the most favourable mosquito habitats. Due to the low density of animal hosts and arid conditions, the desert region showed low RVF suitability, except in oases. However, the presence of competent vectors in putative unsuitable areas underlines the need for further assessments of mosquito habitat preference. This study produced monthly RVF suitability maps useful for animal health managers and veterinary services involved in designing risk-based surveillance programmes. The suitability maps can be further enhanced using existing country-specific sources of information and by incorporating knowledge - as it becomes available - on the epidemiology of the disease and distribution of vectors in the Maghreb.
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Affiliation(s)
- E Arsevska
- Unité Epidémiologie, Laboratoire de Lyon, Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES), Lyon, France
| | - J Hellal
- Institut de Recherche Vétérinaire de Tunisie (IRVT), Tunis, Tunisie
| | - S Mejri
- Institut de Recherche Vétérinaire de Tunisie (IRVT), Tunis, Tunisie
| | - S Hammami
- Centre Nationale de Veille Zoosanitaire (CNVZ), Tunis, Tunisie
| | - P Marianneau
- Unité Virologie, Laboratoire de Lyon, Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES), Lyon, France
| | - D Calavas
- Unité Epidémiologie, Laboratoire de Lyon, Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES), Lyon, France
| | - V Hénaux
- Unité Epidémiologie, Laboratoire de Lyon, Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES), Lyon, France.
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