Rift valley fever virus rvfv is a zoonotic pathogen that primarily affects ruminants but can. Table iv from rift valley fever virus bunyaviridae. An outbreak of rift valley fever virus rvfv infection affected sheep, goats, cattle and wildlife on farms within free state, eastern cape, northern cape, western cape, mpumalanga, north west, and gauteng provinces. As of 29 march 2010, about 78 farms reported laboratoryconfirmed animal cases, with extensive livestock deaths. Rift valley fever symptoms, diagnosis and treatment bmj. Rift valley fever rvf national center for emerging and zoonotic infectious diseases division of highconsequence pathogens and pathology dhcpp rift valley fever rvf is an acute, fever causing viral disease most commonly observed in domesticated animals such as cattle, buffalo. Spread of rvfv out of africa has raised concerns that it could emerge in europe or the usa. Rift valley fever virus rvfv is a mosquitoborne arbovirus causing severe disease in humans and ruminants. Several animal models have been developed to gain insight into the pathogenesis associated with aerosolized rvfv infection, but work with these models is restricted to high containment biosafety level bsl. Pathogenesis of rift valley fever rvf in swiss albino mice experimenentally infected with rvf virus. Rift valley fever rvf is an acute viral disease that affects domestic animals such as cattle, buffalo, sheep, goats, and camels. Facts about rift valley fever european centre for disease.
Experimental infection rate ir, transmission rate tr and vector competence index vci for rift valley fever virus in mosquito species from which rvfv has been isolated in the wild. Large outbreaks of clinical disease are usually associated with heavy rainfall and localized flooding. Rift valley fever virus rvfv is an emerging pathogen capable of causing severe disease in livestock and humans and can be transmitted by multiple routes including aerosol exposure. The virus is transmitted by mosquitoes, and virus replication in domestic ruminant. Rift valley fever rvf is a peracute or acute, mosquitoborne, zoonotic disease of domestic and wild ruminants in africa, madagascar, and the arabian peninsula. Rift valley fever virus induces fetal demise in sprague. Rift valley fever rvf virus is a negativesense, trisegmented rna virus of the. The rift valley fever virus protein nsm and putative cellular. There are several genetic lineages of this virus, some of which may cocirculate, in endemic regions.
The pathogenesis of rift valley fever pubmed central pmc. Rift valley fever virus an overview sciencedirect topics. Rift valley fever virus rvfv infections in pregnant livestock cause high rates of fetal demise. Scientists have characterized the mechanism used by the virus to insert one of its. A virus even more dangerous than zika to pregnant women. Molecular aspects of rift valley fever virus and the. Jul 28, 2012 rift valley fever is an infectious viral disease and an emerging problem in many countries of africa and on the arabian peninsula. Presenting symptom in 90% of patients, and is often 39c with a remitting pattern. Humans are highly susceptible to infection but represent dead end hosts. Infection with rift valley fever rvf virus, a phlebovirus, appears to be regulated by interferon and terminated by neutralizing antibody. Rvf is endemic to subsaharan african countries and has caused major outbreaks in several countries. Coatzer jaw 1977 the pathology of rift valley fever 1.
Rift valley fever virus rvfv was first isolated in 1930 from sheep during an epizootic causing abortion and death in the rift valley near lake niavasha, kenya, but is present from south africa to egypt. The virus was identified in 1930 along the shores of lake naivasha in the great rift valley in kenya 1,2. Rift valley fever aetiology epidemiology diagnosis prevention and control references aetiology classification of the causative agent rift valley fever rvf virus is a negativesense, trisegmented rna virus of the within the order bunyavirales, family phenuiviridae, genus phlebovirus. The virus is transmitted by mosquitoes, and virus replication in domestic ruminant results in high rates. First identified in kenya in 1931 3, rvfv is now considered an endemic zoonotic agent in subsaharan africa causing explosive outbreaks in animals and humans.
Pdf the pathogenesis of rift valley fever researchgate. Rift valley fever is a primarily mosquitoborne, multispecies zoonotic viral disease of which the causative organism, rift valley fever virus, was first isolated in the early 1930s in the rift valley in kenya. Symptoms of mild illness such as fever and body aches can be managed with standard overthecounter medications. Because most cases of rvf are mild and selflimiting, a specific treatment for rvf has not been established. Rift valley fever virus is responsible for outbreaks in livestock in africa and can also be fatal in humans. Rift valley fever rvf virus is unique among the phleboviruses in its pathogenicity for humans and domestic animals, its various routes of infection, and its wide host range.
This virus causes severe disease in humans and animals. It is named after the great rift valley in kenya where it was first discovered in livestock in the early 1910s. The pathogenesis of rift valley fever virus in the mouse. Rift valley fever rvf is an acute, fever causing viral disease most commonly observed in domesticated animals such as cattle, buffalo, sheep, goats, and camels, with the ability to infect and cause illness in humans. The disease is caused by rvf virus rvfv, a member of the genus phlebovirus in the family bunyaviridae. The virus is transmitted by mosquitoes, and virus replication in domestic ruminant results in high rates of mortality and abortion. Pathogenesis of rift valley fever in humans human emerging. Classification of the causative agent resistance to physical. A fully characterized small animal model of rvf is needed to evaluate potential. Rift valley fever rvf, which is endemic to subsaharan africa2 and threatens to spread even further, regionally and internationally. A fully characterized small animal model of rvf is needed to evaluate potential vaccines and therapeutics.
There are no fdaapproved treatments for rift valley fever. Pdf pathogenesis of rift valley fever rvf in swiss. In spite of clinically useful similarities among various vhfs, there are significant differences in their pathogenesis and clinical evolution. The disease is caused by the rvf virus, generally found in regions of eastern and southern africa, but also in most countries of subsaharan africa, madagascar, saudi arabia and yemen. Potential for autoimmune pathogenesis of rift valley fever virus.
Detailed studies describing the pathogenesis of rift valley fever rvf virus rvfv in the mouse model are lacking. Keywords control ecology mosquito pathogenesis prevention rift valley fever. Rvfv is a threat to both animal and human health and has costly economic consequences mainly related to livestock production and trade. Rift valley fever and a new paradigm of research and. Rift valley fever rvf is a viral zoonosis that primarily affects animals but can also infect humans. The two faces of rift valley fever virus virulence factor nss. We found that pregnant rats were more susceptible to rvfvinduced death than. Overview of rift valley fever generalized conditions. Terasaki k, makino s 2015 interplay between the virus and host in rift valley fever pathogenesis. The zika virus must take the side roads into the placenta to infect a fetus, one researcher said but the rift valley fever virus takes the expressway.
The disease is caused by the rift valley fever virus rvfv of the family bunyaviridae and the genus phlebovirus. Rift valley fever disease rift valley fever rvf is a viral zoonosis that primarily affects animals but can also infect humans rvf outbreaks have been reported in subsaharan africa and egypt. To address how rvfv infection during pregnancy causes detrimental effects on the fetus, we developed a pregnant rodent model of rvfv infection. Rift valley fever in the latest edition of the oie manual of diagnostic tests and. Pdf potential for autoimmune pathogenesis of rift valley. The virus is transmitted by mosquitoes, and virus replication in. Rift valley fever results from infection by the rift valley fever virus, an rna virus in the genus phlebovirus in the family bunyaviridae. Rift valley fever in namibia, 2010 volume 19, number 12. Rift valley fever molecular epidemiology vector pathogenesis diagnostic table of contents 1. Rift valley fever virus rvfv is a phlebovirus of the bunyaviridae family. Rift valley fever rvf is an acute, fevercausing viral disease most commonly observed in domesticated animals such as cattle, buffalo, sheep, goats, and camels, with the ability to infect and cause illness in humans. Only one serotype is recognised but strains exist of.
Pathogenesis of rift valley fever virus aerosol infection in. Rift valley fever history and exam bmj best practice. This rapid risk assessment rra addresses the risk of importation of rift valley fever rvf virus rvfv and. Introduction to rift valley fever world health organization. In this study, we characterized the pathogenesis of rvfv throughout the disease course in mice. The disease is caused by the rift valley fever virus rvfv of the. Aedes mosquito saliva modulates rift valley fever virus. The virus belongs to the bunyaviridae family genus phlebovirus. In 2000, cases were confirmed in saudi arabia and yemen, raising concerns that it could extend to other parts of asia and europe. Potential for autoimmune pathogenesis of rift valley fever virus retinitis. Rift valley fever rvf is an emerging zoonotic disease distributed in subsaharan african countries and the arabian peninsula.
Vertical transmission in mosquitoes and viral transmission between animals and mosquitoes allows rvfv to persist in endemic areas in africa. The causative virus is predominantly transmitted by mosquitoes and high mortality and abortion rates characterize outbreaks in animals while symptoms ranging from mild to lifethreatening encephalitis and hemorrhagic fever are noticed among infected humans. Pdf the pathogenesis of rift valley fever virus in the. Competent hosts and vectors for rvfv are widespread, existing outside of endemic countries including the usa. Viruses free fulltext the pathogenesis of rift valley fever. Rift valley fever in chronic carrier and liver manifestations.
To date, no humantohuman transmission of rvf virus has been documented. Although rift valley fever is a disease that, through its wider societal effects, disproportionately affects vulnerable communities with poor resilience to economic and environmental challenge, rift valley fever virus has since its discovery in 1931 been neglected by major global donors and disease control programs. Nov 20, 2015 rift valley fever rvf is an important zoonotic disease in africa and the arabian peninsula, and the potential spread into non. Nov, 2018 rift valley fever phlebovirus rvfv is a mosquitotransmitted pathogen endemic to subsaharan africa and the arabian peninsula. Interplay between the virus and host in rift valley fever pathogenesis. The pathogenesis of rift valley fever virus in the mouse model. Lesions occurring in natural cases in newborn lambs. Human infections have also resulted from the bites of infected mosquitoes. It is characterized by a threesegmented genome of negativeambisense strand rna in viral nucleocaspid protein and enveloped by a lipid bilayer containing two viral glycoproteins, gn and gc like all members of the virus family 5. Rapid risk assessment rift valley fever outbreak in mayotte, france 7 march 2019 2 source and date of request. Rift valley fever virus rvfv is a zoonotic mosquitoborne virus which causes epizootics and associated human epidemics throughout africa 1,2. Rift valley fever rvf is a zoonotic, mosquitoborne viral disease that affects human health and causes significant losses in the livestock industry. Rift valley fever rvf, a mosquitoborne zoonotic disease among humans and ruminants, is caused by rift valley fever virus rvfv belonging to family bunyaviridae, genus phlebovirus1,2.
May 06, 2011 rift valley fever rvf is an emerging zoonotic disease distributed in subsaharan african countries and the arabian peninsula. Rift valley fever virus rvfv is a zoonotic arbovirus and a pathogen of rvf which is endemic in subsaharan african countries 1. Epidemiology and pathogenesis of rift valley fever and other. The virus infects many large domestic animals and a wide variety of mosquito species, with sheep, cattle, buffaloes. The virus is transmitted by mosquitoes, and virus replication in domestic ruminant results in. It is the cause of severe disease in small stock resulting in high mortality and abortion storms particularly in sheep and goats.
486 1497 554 1413 439 1618 1220 132 563 203 472 1187 531 1201 1414 1011 181 1164 8 1528 42 396 925 894 1398 429 847 60 611 519 1418 708 867 1307 700 1015 1285 814 931 344