Bwamba Fever
Encyclopedia
Bwamba Fever virus
is from the genus Orthobunyavirus
and belongs to the order Bunyaviridae
. It has a negative sense single stranded RNA (ssRNA) genome, and so is classified as a class V virus under the Baltimore classification
system. The genome is segmented into three pieces, Large (L), Medium (M) and Small (S), which have a combined length of approximately 12,000nt. The S RNA encodes a nucleocapsid and non structural proteins, the M RNA encodes envelope glycoproteins and a non structural membrane polypeptide and the L RNA encodes an RNA dependent RNA polymerase
.
complex, that associates with RNA dependent RNA polymerase. The complex is surrounded by a lipid layer, into which the nuclear complex interacts. Finally the particle is membrane bound, spherical, and in total is approximately 100 nm in diameter.
To replicate the genome, transcription occurs to produce a replicative intermediate, which is then itself transcribed into new RNA genomes, with the aid of the RNA polymerases produced from the gene expression.
, and was only identified in the later 1990’s and is believed to be endemic in east Africa, especially Kenya, Tanzania and Uganda, where the virus was first identified by the Uganda Virus Research Institute
. There is no specific treatment for the virus, as it causes only a mild fever.
Virus
A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...
is from the genus Orthobunyavirus
Orthobunyavirus
Orthobunyavirus is a genus of the Bunyaviridae family.The genus is most diverse in Africa, Australia and Oceania, but occurs almost world-wide...
and belongs to the order Bunyaviridae
Bunyaviridae
Bunyaviridae is a family of negative-stranded RNA viruses. Though generally found in arthropods or rodents, certain viruses in this family occasionally infect humans. Some of them also infect plants....
. It has a negative sense single stranded RNA (ssRNA) genome, and so is classified as a class V virus under the Baltimore classification
Baltimore classification
The Baltimore classification, developed by David Baltimore, is a virus classification system that groups viruses into families, depending on their type of genome and their method of replication....
system. The genome is segmented into three pieces, Large (L), Medium (M) and Small (S), which have a combined length of approximately 12,000nt. The S RNA encodes a nucleocapsid and non structural proteins, the M RNA encodes envelope glycoproteins and a non structural membrane polypeptide and the L RNA encodes an RNA dependent RNA polymerase
RNA polymerase
RNA polymerase is an enzyme that produces RNA. In cells, RNAP is needed for constructing RNA chains from DNA genes as templates, a process called transcription. RNA polymerase enzymes are essential to life and are found in all organisms and many viruses...
.
Virus Structure
The segmented RNAs are surrounded by nucleocapsid proteins that form a RibonucleoproteinRibonucleoprotein
Ribonucleoprotein is a nucleoprotein that contains RNA, i.e. it is an association that combines ribonucleic acid and protein together. A few known examples include the ribosome, the enzyme telomerase, vault ribonucleoproteins, and small nuclear RNPs , which are implicated in pre-mRNA splicing and...
complex, that associates with RNA dependent RNA polymerase. The complex is surrounded by a lipid layer, into which the nuclear complex interacts. Finally the particle is membrane bound, spherical, and in total is approximately 100 nm in diameter.
Gene expression and genome replication
Once inside a host cell cytoplasm, the genomic RNA’s are transcribed into mRNA’s by the associated RNA polymerase. From these transcripts, the host machinery is used for translation into viral proteins. The S segment is slightly different from the rest as it is ambisense, meaning genes run in both the positive and negative directions. To enable correct translation of the proteins, a second round of transcription has to occur.To replicate the genome, transcription occurs to produce a replicative intermediate, which is then itself transcribed into new RNA genomes, with the aid of the RNA polymerases produced from the gene expression.
Bwamba Fever
Bwamba fever virus is transmitted from vertebrate to vertebrate through a mosquito vector, Anopheles funestus, and causes Bwamba fever. The fever is often mistaken for malariaMalaria
Malaria is a mosquito-borne infectious disease of humans and other animals caused by eukaryotic protists of the genus Plasmodium. The disease results from the multiplication of Plasmodium parasites within red blood cells, causing symptoms that typically include fever and headache, in severe cases...
, and was only identified in the later 1990’s and is believed to be endemic in east Africa, especially Kenya, Tanzania and Uganda, where the virus was first identified by the Uganda Virus Research Institute
Uganda Virus Research Institute
The Uganda Virus Research Institute , located in Entebbe, Uganda, was established in 1936 as the Yellow Fever Research Institute by the Rockefeller Foundation. In 1950, after gaining regional recognition it was renamed the East African Virus Research institute...
. There is no specific treatment for the virus, as it causes only a mild fever.