How does Lassa virus reproduce?
The virus replicates through a strategy known as the Ambisense, where two RNA strands code for genes in both the sense and antisense direction that is rapid and demonstrate temporal control in replication.
Is Lassa virus RNA or DNA?
Lassa fever is an acute viral haemorrhagic illness caused by Lassa virus, a member of the arenavirus family of viruses. Humans usually become infected with Lassa virus through exposure to food or household items contaminated with urine or faeces of infected Mastomys rats.
What is the mode of transmission of Lassa fever?
How Does Lassa Fever Spread? A type of rodent called the multimammate rat carries the Lassa fever virus in its pee and poop. There are lots of these rats in West, Central, and East Africa. They tend to live in homes and in other areas where people store food.
How does Lassa virus enter the cell?
Upon receptor binding, LASV enters the host cell via receptor-mediated endocytosis, with subsequent transport to late endosomal compartments, where fusion occurs at low pH (3, 4).
What is the vector of Lassa fever?
Lassa fever is endemic in parts of west Africa including Sierra Leone, Liberia, Guinea and Nigeria; however, other neighboring countries are also at risk, as the animal vector for Lassa virus, the “multimammate rat” (Mastomys natalensis) is distributed throughout the region.
What are the prevention and control of Lassa fever?
Prevention of Lassa fever relies on promoting good “community hygiene” to discourage rodents from entering homes. Effective measures include storing grain and other foodstuffs in rodent-proof containers, disposing of garbage far from the home, maintaining clean households and keeping cats.
What is the scientific name for Lassa virus?
Lassa mammarenavirus (Lassavirus) is a vector-borne virus consisting of bipartite single-stranded, ambisense RNA genomes. It is a member of the Arenaviridae family (genus= Mammarenavirus) and infects rodents and humans. Lassavirus is named for Lassa village in Nigeria where two nurses became infected in 1969.
What causes bleeding in Lassa fever?
Lassa fever is an acute, viral disease carried by a type of rat that is common in West Africa. It can be life-threatening. It is a hemorrhagic virus, which means it can cause bleeding, although 8 out of every 10 people with the virus have no symptoms. If it affects the liver, kidneys, or spleen, it can be fatal.
Does Lassa virus have envelope?
Lassa virus is an enveloped virus with glycoprotein spikes on its surface. It contains an RNA ambisense genome that encodes the glycoprotein precursor GP-C, the nucleoprotein NP, the polymerase L, and the Z protein.
Why is Lassa fever called a fever?
The first documented case occurred in 1969. Lassa fever is named after the town in Nigeria where the first cases occurred. About 100,000 to 300,000 infections of Lassa fever occur annually, with about 5,000 deaths. Surveillance for Lassa fever varies between locations so these estimates are crude.
What is the incubation period of Lassa fever?
The incubation period for disease is usually between 7 and 10 days, with a maximum of 21 days. The onset of illness is insidious, with: fever and shivering. malaise.
What cells does Lassa virus infect?
Antigen-presenting cells (APC)—dendritic cells (DC) and macrophages (MP)—are probably the first cells targeted by LASV [20,21]. The widespread distribution of these cells in the mucosal tissues and skin, results in their early infection, allowing the first replicative cycles to occur.
Is Lassa fever enveloped?
What is the prevention of Lassa fever?
Primary transmission of the Lassa virus from its host to humans can be prevented by avoiding contact with Mastomys rodents, especially in the geographic regions where outbreaks occur. Putting food away in rodent-proof containers and keeping the home clean help to discourage rodents from entering homes.
What organs does Lassa fever affect?
About 80% of people who become infected with Lassa virus have no symptoms. 1 in 5 infections result in severe disease, where the virus affects several organs such as the liver, spleen and kidneys. Lassa fever is a zoonotic disease, meaning that humans become infected from contact with infected animals.
What is the size of Lassa virus?
Lassa virus is spherical in shape and is a medium-sized agent that measures between 70 and 150 nm in diameter (Figure 1). It has been classified into the arenaviridae family. A typical mature Lassa virus particle possesses a glycoprotein envelope with T-shaped spikes measuring 7–10 nm on its surface.
Is Lassa fever virus an RNA virus?
The virus is a single-stranded RNA virus belonging to the virus family Arenaviridae. About 80% of people who become infected with Lassa virus have no symptoms. 1 in 5 infections result in severe disease, where the virus affects several organs such as the liver, spleen and kidneys.
Is Lassa fever positive or negative sense?
Lassa virus, the causative agent of Lassa fever, belongs to the family Arenaviridae. Arenaviruses are classified as segmented negative-sense RNA (nsRNA) viruses and are phylogenetically closely related to other segmented nsRNA viruses belonging to Bunyaviridae and Orthomyxoviridae.
Is Lassa virus positive or negative-sense?
Lyssaviruses are bullet-shaped, single-stranded, negative-sense RNA viruses and the causative agents of the ancient zoonosis rabies.
What are the risk factors of Lassa fever?
Individuals at greatest risk of Lassa virus infection are those who live in or visit endemic regions, including Sierra Leone, Liberia, Guinea, and Nigeria and have exposure to the multimammate rat. Risk of exposure may also exist in other west African countries where Mastomys rodents exist.
What is rage virus?
Jump to navigation Jump to search. Rage is a fictional virus appearing in the 2002 film 28 Days Later directed by Danny Boyle, and in the 2007 film 28 Weeks Later directed by Juan Carlos Fresnadillo. It also appears in the graphic novel 28 Days Later: The Aftermath.
What is genomic RNA?
The RNA genome is the template for synthesis of additional RNA strands (a molecule of RNA is the template and molecules of RNA are produced). During replication of RNA viruses, there are at least three types of RNA that must be synthesized: the genome, a copy of the genome (copy genome), and mRNAs.
What is the Trixie virus?
Trixie is an unknown toxin/disease blamed for infecting local townspeople via consumption of the contaminated water supply from Hopman Bog in Ogden Marsh, gradually transforming its victims into mindless, calculative, depraved, bloodthirsty killers preying on neighbors and families, including strangers seen in the 1973 …
Why is it called 28 Days Later?
At around the same time, a bicycle courier in London, named Jim, was hit by a car while delivering a package to Shaftsbury Avenue, and taken to hospital, where he slipped into a coma (28 Days Later (film)).
What are the 3 types of genomes?
There are four main types of genome-wide repeat, called LINEs (long interspersed nuclear elements), SINEs (short interspersed nuclear elements), LTR (long terminal repeat) elements and DNA transposons. Examples of each type are seen in this short segment of the genome.