Spondweni virus

Last updated
Spondweni virus
Virus classification OOjs UI icon edit-ltr.svg
(unranked): Virus
Realm: Riboviria
Kingdom: Orthornavirae
Phylum: Kitrinoviricota
Class: Flasuviricetes
Order: Amarillovirales
Family: Flaviviridae
Genus: Flavivirus (?)
Virus:
Spondweni virus

Spondweni virus (SPOV or SPONV) is an arbovirus, or arthropod-borne virus, which is a member of the family Flaviviridae and the genus Flavivirus . [1] [2] It is part of the Spondweni serogroup which consists of the Sponweni virus and the Zika virus (ZIKV). [1] [3] The Spondweni virus was first isolated in Nigeria in 1952, and ever since, SPONV transmission and activity have been reported throughout Africa. [4] [1] Its primary vector of transmission is the sylvatic mosquito Aedes circumluteolus , though it has been isolated from several different types of mosquito. [1] Transmission of the virus into humans can lead to a viral infection known as Spondweni fever, with symptoms ranging from headache and nausea to myalgia (muscle pain) and arthralgia (joint pain). [1] [3] However, as SPONV is phylogenetically close to the ZIKV, it is commonly misdiagnosed as ZIKV along with other viral illnesses. [1] [3]

Contents

Virology

The Spondweni virus belongs to the family Flaviviridae and the genus Flavivirus . [1] Due to its phylogeny, it is related to the dengue virus, yellow fever virus, Japanese encephalitis virus, and West Nile virus. [5] [6] [7] It is part of the Spondweni serogroup which also contains the Zika virus. [3] [7] However, in certain Spondweni virus cases, signs and symptoms can appear as early as three days after infection. [3] Both of these viruses in the Spondweni serogroup have serological cross-reactivity and very similar clinical presentations. [3] This is one of the primary reasons that both viruses and their correlated diseases have been misidentified and misdiagnosed. [1] [3]

Similar to other flaviviruses, SPONV has a positive-sense, single stranded RNA genome, which is about 11 kilobases in length. [1] The RNA genome contains 5' and 3' untranslated regions that surround a single open reading frame that encodes for a polyprotein that is specifically cleaved. [1] The polyprotein is cleaved into three specific proteins: the capsid (C), the premembrane (prM), and the envelope (E), along with seven non-structural proteins (NS1, NS2A, NS2B, NS3, NS4A, 2K, NS4B, and NS5). [1] [6] The SPONV capsid is icosahedral and the similar to other flaviviruses which have an enveloped consisting of glycoproteins. [1] [6] These glycoproteins aid the virus in infection, through receptor mediated endocytosis. [8] Two strains of the Spondweni virus have been reported, the Chuku strain and the SA Ar 94 strain. [1] The Chuku strain was the original strain isolated from a patient in Nigeria in 1952. [1] This strain was originally misclassified as Zika virus, and this misidentification eventually lead to the 1955 South African SA 94 isolation from the Mansonia uniformis mosquito. [1] Both isolated SPONV strains are genetically similar, but they do exhibit a high degree of amino acid and nucleotide divergence, compared to the multiple ZIKV strains. [1] [3]

Life cycle and reproduction

Flaviviruses, including SPONV, have a conserved replication cycle. The conserved replication cycle consists of viral entry, virion fusion with the endosome and release of viral RNA, genome replication and protein production in the endoplasmic reticulum, virion packaging and processing through the secretory pathway, and viral release via exocytosis. Flaviviruses use the host machinery to perform all these operations. Since the genome size of flaviviruses is small, flaviviruses maximize their use of the encoded proteins. Most of flavivirus replication is dependent on the interactions between viral proteins and host proteins. A unique step in the viral replication cycle of flaviviruses is viral entry. For flaviviruses, Env proteins on the virion exterior interact and attach to host factors on the plasma membrane surface. Env proteins can bind many different host factors. Variations in Env protein sequence cause the differences in tissue tropisms between flaviviruses. [9]

Transmission

Similar to Zika, the Spondweni virus's primary vector of transmission is mosquitos from the genus Aedes . [1] The two Spondweni virus strains have been isolated from multiple mosquito genera including Aedes fryeri/fowleri, Aedes circumluteolus, Aedes cumminsi, Culex neavi, Culex univittatus, Eretmapodites silvestris, Mansonia africana, and Mansonia uniformis. However, the majority of SPONV isolations have been from one species of sylvatic mosquito, Ae. circumluteolus. [1]

The degree of infection and dissemination of both strains differs by primary vector species. In regards to Chuku strain, no detectable infection or dissemination has been found in two different Aedes species (Ae. albopictus and Ae. aegypti) along with Culex quinquefasciatus. [1] The SA Ar 94 strain had been observed causing dissemination infection in Ae. albopictus, but the other two resulted in failed transmission. [1] When the Chuku stain of SPONV was tested to see if it could successfully transmit into the Ae. aegypti mosquito (the dominant vector of ZIKV), it failed. [1]

Little information is available on the potential amplification and maintenance of SPONV in numerous hosts species. [1] [10] Intensive field studies have been carried out in areas with high SPONV transmission, to eliminate potential host species. [11] Numerous isolations of both SPONV strain types along with evidence of antibodies to the two strains were not detected in any rodent or birds collected in South Africa in 1958, leading to the speculation that these species were unlikely amplification and transmission of the virus. [1] [12] Experimental work has demonstrated that SPONV can infect non-human primates. [1] Due to its serological cross-reactivity and similar clinical presentations with ZIKV, SPONV may be maintained and transmitted in a sylvatic cycle to nonhuman primates and certain species of mosquitoes. [3]

Signs and symptoms

Successful transmission and infection by either SPONV strain can result in the infectious disease known as Spondweni fever. Less is known about the clinical presentation of Spondweni virus infections, since a large problem with misdiagnosis is seen, as other viral infections like Zika. [1] The majority of SPONV infections have been reported as asymptomatic. [3] However, in certain Spondweni virus cases, signs and symptoms can appear as early as three days after infection. [3] Six cases of Spondweni virus infections have been well documented, and the signs and symptoms parallel closely to Zika fever. [3] Symptoms included:

While most reported symptomatic Spondweni virus infections have mild to moderate febrile illness that last for a short duration, incidences[ spelling? ] of more serious symptoms and illnesses have been associated with the virus. More serious complications have occurred, including conjunctivitis, hematuria, hematospermia, aphthous ulcer, and epistaxis. [1] [12] [13]

Diagnosis of Spondweni viral infection would be to screen blood samples from infected individuals for the presence of the positive-sense, single-stranded RNA virion through the use of serologic assay, virus isolation, or PCR/qPCR. [3] These methods also aid in the prevention of misdiagnosis of Spondweni viral infection with other viral infections and infections with a similar clinical symptom array which includes Zika fever, dengue fever, Lassa fever, rickettsial infection, leptospirosis, and typhoid fever. [13]

Evolution

SPONV and Zika (ZIK) virus are two closely related flaviviruses. Humans infected by both viruses demonstrate similar symptoms. [14] This suggests that SPONV and ZIK have a similar evolutionary history. The evolution and dispersal patterns of flaviviruses are determined by arthropod vectors, the vertebrate hosts, the ecology nearby, and the influence of human commercial activity. For example, the increase and expansion of Aedes clade viruses in the tropics is due to an increase in human and mosquito population densities brought about by urbanization and industrialization. ZIK virus, SPON virus (SPONV), DEN virus, and KED virus are in the same clade. This clade is known as the Aedes clade, named after the genus of mosquito that primarily acts as hosts for these viruses. Blood-meal data from the Aedes genus demonstrate that mammals are the main hosts of most species. The hosts of the Culex genus, another genus of mosquitoes, are birds. Both these observations support the relationships between Aedes-borne flaviviruses and mammals or between Culex-borne flaviviruses and birds. All the viruses in the Aedes clade are isolated from Africa. This suggests that the earliest evolutionary lineage of these mosquito-borne viruses must have moved to Afro-Eurasia (Old World) and to a large variety of species, including sandflies and large animals, including simians and humans. This explains why SPONV and ZIK are not solely in Africa. [15]

Related Research Articles

<i>Flaviviridae</i> Family of viruses

Flaviviridae is a family of enveloped positive-strand RNA viruses which mainly infect mammals and birds. They are primarily spread through arthropod vectors. The family gets its name from the yellow fever virus; flavus is Latin for "yellow", and yellow fever in turn was named because of its propensity to cause jaundice in victims. There are 89 species in the family divided among four genera. Diseases associated with the group include: hepatitis (hepaciviruses), hemorrhagic syndromes, fatal mucosal disease (pestiviruses), hemorrhagic fever, encephalitis, and the birth defect microcephaly (flaviviruses).

<i>Flavivirus</i> Genus of viruses

Flavivirus is a genus of positive-strand RNA viruses in the family Flaviviridae. The genus includes the West Nile virus, dengue virus, tick-borne encephalitis virus, yellow fever virus, Zika virus and several other viruses which may cause encephalitis, as well as insect-specific flaviviruses (ISFs) such as cell fusing agent virus (CFAV), Palm Creek virus (PCV), and Parramatta River virus (PaRV). While dual-host flaviviruses can infect vertebrates as well as arthropods, insect-specific flaviviruses are restricted to their competent arthropods. The means by which flaviviruses establish persistent infection in their competent vectors and cause disease in humans depends upon several virus-host interactions, including the intricate interplay between flavivirus-encoded immune antagonists and the host antiviral innate immune effector molecules.

<span class="mw-page-title-main">Arbovirus</span> Common name for several species of virus

Arbovirus is an informal name for any virus that is transmitted by arthropod vectors. The term arbovirus is a portmanteau word. Tibovirus is sometimes used to more specifically describe viruses transmitted by ticks, a superorder within the arthropods. Arboviruses can affect both animals and plants. In humans, symptoms of arbovirus infection generally occur 3–15 days after exposure to the virus and last three or four days. The most common clinical features of infection are fever, headache, and malaise, but encephalitis and viral hemorrhagic fever may also occur.

<i>Bunyavirales</i> Order of RNA viruses

Bunyavirales is an order of segmented negative-strand RNA viruses with mainly tripartite genomes. Member viruses infect arthropods, plants, protozoans, and vertebrates. It is the only order in the class Ellioviricetes. The name Bunyavirales derives from Bunyamwera, where the original type species Bunyamwera orthobunyavirus was first discovered. Ellioviricetes is named in honor of late virologist Richard M. Elliott for his early work on bunyaviruses.

<i>Alphavirus</i> Genus of viruses

Alphavirus is a genus of RNA viruses, the sole genus in the Togaviridae family. Alphaviruses belong to group IV of the Baltimore classification of viruses, with a positive-sense, single-stranded RNA genome. There are 32 alphaviruses, which infect various vertebrates such as humans, rodents, fish, birds, and larger mammals such as horses, as well as invertebrates. Alphaviruses that could infect both vertebrates and arthropods are referred dual-host alphaviruses, while insect-specific alphaviruses such as Eilat virus and Yada yada virus are restricted to their competent arthropod vector. Transmission between species and individuals occurs mainly via mosquitoes, making the alphaviruses a member of the collection of arboviruses – or arthropod-borne viruses. Alphavirus particles are enveloped, have a 70 nm diameter, tend to be spherical, and have a 40 nm isometric nucleocapsid.

<span class="mw-page-title-main">Mosquito-borne disease</span> Diseases caused by bacteria, viruses or parasites transmitted by mosquitoes

Mosquito-borne diseases or mosquito-borne illnesses are diseases caused by bacteria, viruses or parasites transmitted by mosquitoes. Nearly 700 million people get a mosquito-borne illness each year resulting in over 725,000 deaths.

<i>Zika virus</i> Species of flavivirus

Zika virus is a member of the virus family Flaviviridae. It is spread by daytime-active Aedes mosquitoes, such as A. aegypti and A. albopictus. Its name comes from the Ziika Forest of Uganda, where the virus was first isolated in 1947. Zika virus shares a genus with the dengue, yellow fever, Japanese encephalitis, and West Nile viruses. Since the 1950s, it has been known to occur within a narrow equatorial belt from Africa to Asia. From 2007 to 2016, the virus spread eastward, across the Pacific Ocean to the Americas, leading to the 2015–2016 Zika virus epidemic.

Rocio viral encephalitis is an epidemic flaviviral disease of humans first observed in São Paulo State, Brazil, in 1975. Low-level enzootic transmission is likely continuing in the epidemic zone, and with increased deforestation and population expansion, additional epidemics caused by Rocio virus are highly probable. If migratory species of birds are, or become involved in, the virus transmission cycle, the competency of a wide variety of mosquito species for transmitting Rocio virus experimentally suggest that the virus may become more widely distributed. The encephalitis outbreak in the western hemisphere caused by West Nile virus, a related flavivirus, highlights the potential for arboviruses to cause severe problems far from their source enzootic foci.

<i>Usutu virus</i> Species of virus

Usutu virus (USUV) is a flavivirus belonging to the Japanese encephalitis complex, which is an emerging zoonotic arbovirus of concern because of its pathogenicity to humans and its similarity in ecology with other emerging arboviruses such as West Nile virus. It mainly infects Culex mosquitoes and birds; humans form a dead-end host. First identified in South Africa in 1959, the virus has caused outbreaks in birds across Europe since 1996. Nearly 50 cases in humans have been reported as of 2019, mainly in Europe. These are predominantly asymptomatic, but some people experience neurological symptoms.

<i>Seadornavirus</i> Genus of viruses

Seadornavirus is a genus of viruses, in the family Reoviridae, in the subfamily Sedoreovirinae. Human, cattle, pig, and mosquitoes serve as natural hosts. There are three species in this genus: Banna virus (BAV), Kadipiro virus and Liao ning virus. Each of these viruses has been isolated from Aedes, Anopheles and Culex mosquito populations, but only BAV has been shown to cause infection in humans, in which the symptoms are similar to Japanese encephalitis—fever, malaise and encephalitis. The word seadornavirus is an portmanteau, meaning Southeast Asian dodeca RNA virus.

<span class="mw-page-title-main">2007 Yap Islands Zika virus outbreak</span> Disease outbreak in the Federated States of Micronesia

The 2007 Yap Islands Zika virus outbreak represented the first time Zika virus had been detected outside Africa and Asia. It occurred in the Yap Islands, an island chain in the Federated States of Micronesia. Zika virus (ZIKV) is a vector-borne flavivirus in the same family as yellow fever, dengue, West Nile and Japanese encephalitis viruses.

Batai orthobunyavirus (BATV) is a RNA virus belonging to order Bunyavirales, genus Orthobunyavirus.

Royal Farm virus, previously known as Karshi virus, was not viewed as pathogenic or harmful to humans. Although infected people suffer with fever-like symptoms, some people in Uzbekistan have reported with severe disease such as encephalitis and other large outbreaks of fever illness connected infection with the virus.

<i>West Nile virus</i> Species of flavivirus causing West Nile fever

West Nile virus (WNV) is a single-stranded RNA virus that causes West Nile fever. It is a member of the family Flaviviridae, from the genus Flavivirus, which also contains the Zika virus, dengue virus, and yellow fever virus. The virus is primarily transmitted by mosquitoes, mostly species of Culex. The primary hosts of WNV are birds, so that the virus remains within a "bird–mosquito–bird" transmission cycle. The virus is genetically related to the Japanese encephalitis family of viruses. Humans and horses both exhibit disease symptoms from the virus, and symptoms rarely occur in other animals.

<span class="mw-page-title-main">Palm Creek virus</span> Species of virus

Palm Creek virus (PCV) is an insect virus belonging to the genus Flavivirus, of the family Flaviviridae. It was discovered in 2013 from the mosquito Coquillettidia xanthogaster. The female mosquitoes were originally collected in 2010 from Darwin, Katherine, Alice Springs, Alyangula, Groote Eylandt, Jabiru and the McArthur River Mine, and had since been preserved. The discovery was made by biologists at the University of Queensland. The virus is named after Palm Creek, near Darwin, from where it was originally isolated.

Jingmenvirus is a group of positive-sense single-stranded RNA viruses with segmented genomes. They are primarily associated with arthropods and are one of only two known segmented RNA viruses that infect animal hosts. The first group member, the Jingmen tick virus (JMTV), was described in 2014. Another member, the Guaico Culex virus (GCXV), has a highly unusual multicomponent architecture in which the genome segments are separately enclosed in different viral capsids.

Yokose virus (YOKV) is in the genus Flavivirus of the family Flaviviridae. Flaviviridae are often found in arthropods, such as mosquitoes and ticks, and may also infect humans. The genus Flavivirus includes over 50 known viruses, including Yellow Fever, West Nile Virus, Zika Virus, and Japanese Encephalitis. Yokose virus is a new member of the Flavivirus family that has only been identified in a few bat species. Bats have been associated with several emerging zoonotic diseases such as Ebola and SARS.

<i>Sepik virus</i> Mosquito transmitted virus endemic to Papua New Guinea

Sepik virus (SEPV) is an arthropod-borne virus (arbovirus) of the genus Flavivirus and family Flaviviridae. Flaviviridae is one of the most well characterized viral families, as it contains many well-known viruses that cause diseases that have become very prevalent in the world, like Dengue virus. The genus Flavivirus is one of the largest viral genera and encompasses over 50 viral species, including tick and mosquito borne viruses like Yellow fever virus and West Nile virus. Sepik virus is much less well known and has not been as well-classified as other viruses because it has not been known of for very long. Sepik virus was first isolated in 1966 from the mosquito Mansoniaseptempunctata, and it derives its name from the Sepik River area in Papua New Guinea, where it was first found. The geographic range of Sepik virus is limited to Papua New Guinea, due to its isolation.

<i>Modoc virus</i> Species of virus

Modoc virus (MODV) is a rodent-associated flavivirus. Small and enveloped, MODV contains positive single-stranded RNA. Taxonomically, MODV is part of the Flavivirus genus and Flaviviridae family. The Flavivirus genus includes nearly 80 viruses, both vector-borne and no known vector (NKV) species. Known flavivirus vector-borne viruses include Dengue virus, Yellow Fever virus, tick-borne encephalitis virus, and West Nile virus.

Aedes circumluteolus is a species of mosquito that is found throughout much of Sub-Saharan Africa. It is often found in tropical coastal lowlands and Bushveld savanna.

References

  1. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Haddow AD, Nasar F, Guzman H, Ponlawat A, Jarman RG, Tesh RB, et al. (2016) Genetic Characterization of Spondweni and Zika Viruses and Susceptibility of Geographically Distinct Strains of Aedes aegypti, Aedes albopictus and Culex quinquefasciatus (Diptera: Culicidae) to Spondweni Virus. PLoS Negl Trop Dis 10(10): e0005083. https://doi.org/10.1371/journal.pntd.0005083
  2. ↑ Wolfe MS, Calisher CH, McGuire K. Spondweni virus infection in a foreign resident of Upper Volta. Lancet. 1982 Dec 11;2(8311):1306–8. doi: http:// dx.doi.org/10.1016/S0140-6736(82)91511-2 PMID   6128599
  3. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Haddow AD, Woodall JP (2016) Distinguishing between Zika and Spondweni viruses. Bull World Health Organ. 94: 711.
  4. ↑ MacNamara FN. Zika virus: a report on three cases of human infection during an epidemic of jaundice in Nigeria. Trans R Soc Trop Med Hyg. 1954 Mar;48(2):139–45. doi: https://dx.doi.org/10.1016/0035-9203(54)90006-1 PMID   13157159
  5. ↑ McIntosh BM, Jupp PG, De Sousa J (1972) Further isolations of the arboviruses from mosquitoes collected in Tongaland, South Africa, 1960–1968. J Med Entomol 9: 155–159. PMID   4402531
  6. 1 2 3 Kuno G, Chang GJ, Tsuchiya KR, Karabatsos N, Cropp CB. 1998. Phylogeny of the genus Flavivirus. J Virol 72:73–83
  7. 1 2 Faye, Oumar; Freire, Caio C. M.; Iamarino, Atila; Faye, Ousmane; de Oliveira, Juliana Velasco C.; Diallo, Mawlouth; Zanotto, Paolo M. A.; Sall, Amadou Alpha; Bird, Brian (9 January 2014). "Molecular Evolution of Zika Virus during Its Emergence in the 20th Century". PLoS Neglected Tropical Diseases. 8 (1): e2636
  8. ↑ Dai, Lianpan (11 May 2016). "Structures of the Zika Virus Envelope Protein and Its Complex with a Flavivirus Broadly Protective Antibody". Cell Host & Microbe. 19 (5): 696–704. doi:10.1016/j.chom.2016.04.013
  9. ↑ Fishburn, Adam. "Let's get physical: Flavivirus-host protein–protein interactions in replication and pathogenesis. Frontiers". doi: 10.3389/fmicb.2022.847588 .{{cite journal}}: Cite journal requires |journal= (help)
  10. ↑ Theiler M, Downs WG (1973) The arthropod-borne viruses of vertebrates. New Haven and London: Yale University Press
  11. ↑ Kokernot RH, Smithburn KC, Muspratt J, Hodgson B (1957) Studies on arthropod-borne viruses of Tongaland. VIII. Spondweni virus, an agent previously unknown, isolated from Taeniorhynchus (Mansonioides) uniformis. S Afr J Med Sci 22: 103–112. PMID   13506708
  12. 1 2 3 McIntosh BM (1961) Susceptibility of some African wild rodents to infection with various arthropod-borne viruses. Trans R Soc Trop Med Hyg 55: 63–68. PMID   13774008
  13. 1 2 3 Wolfe MS, Calisher CH, McGuire K (1982) Spondweni virus infection in a foreign resident of Upper Volta. Lancet 2: 1306–1308. PMID   6128599
  14. ↑ White, Sarah (2018). "Spondweni Virus in Field-Caught Culex quinquefasciatus Mosquitoes, Haiti, 2016". Emerging Infectious Diseases. 24 (9): 1765–1767. doi:10.3201/eid2409.171957. PMC   6106418 . PMID   30124422.
  15. ↑ Gaunt, Michael W (2001). "Phylogenetic relationships of flaviviruses correlate with their epidemiology, disease association and biogeography". Journal of General Virology. 82 (Pt 8): 1867–1876. doi: 10.1099/0022-1317-82-8-1867 . PMID   11457992 . Retrieved 20 April 2023.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.