Rabies Is A Virus?

Rabies is spread through animals bites of an infected animal. Symptoms involve fever, headache nausea, etc. The animals that can trasmit rabies are cats, dogs, wolves, bats, and more. The reason why rabies is called hydrophobia, “fear of water”, due to how in one of the symptons of rabies, a person will not be able to swallow liquids which causes

* Flaviviruses: share a common size (40-60nm), symmetry (enveloped, icosahedral nucleocapsid), nucleic acid (positive-sense, single stranded RNA approximately 10,000-11,000 bases), and appearance in the electron microscope. Therefore, images of West Nile virus are representative for this group of viruses.

Viruses are microscopic particles that invade and take over both eukaryotic and prokaryotic cells. They consist of two structures, which are the nucleic acid and capsid. The nucleic acid contains all genetic material in the form of DNA or RNA, and is enclosed in the capsid, which is the protein coating that helps the virus attach to and penetrate the host cell. In some cases, certain viruses have a membrane surrounding the capsid, called an envelope. This structure allows viruses to become more stealthy and protected. There are two cycles in which a virus can go into: lytic and lysogenic. The lytic cycle consists of the virus attaching to a cell, injecting its DNA, and creating more viruses, which proceed to destroy the host. On the other hand, the lysogenic cycle includes the virus attaching to the cell, injecting its DNA, which combines with the cell’s DNA in order for it to become provirus. Then, the provirus DNA may eventually switch to the lytic cycle and destroy the host.

RSV belongs to the paramyxovirus family of viruses. The virion encompasses a helical nucleocapsid packaged in a lipoprotein envelope attained from the host cell plasma membrane during budding. The external surface of the envelope contains a periphery of surface spikes.

The virus fuses with the cell’s plasma membrane. The capsid proteins are removed, releasing the viral proteins and RNA. Reverse transcriptase catalyzes the synthesis of a DNA strand complementary to the viral RNA. Reverse transcriptase catalyzes the synthesis of a second DNA strand complementary to the first. The double-stranded DNA is incorporated as a provirus into the cell’s DNA. Proviral genes are transcribed into RNA molecules, which serve as genomes for the next viral generation and as mRNAs for translation into viral proteins. The viral proteins include capsid proteins and reverse transcriptase (made in the cytosol) and envelope glycoproteins (made in the ER). Vesicles transport the glycoproteins from the ER to the cell’s plasma membrane. Capsids are assembled around viral genomes and reverse transcriptase molecules. New viruses bud off from the host cell.

RSV is caused by TLR3 activation. It initiates infections by binding to a cellular receptor and then the viral envelope fuses with the plasma membrane. The virus attaches the cell through the main protein, the G protein and fuses with the plasma membrane of the host cell through the F protein. After penetration, the nucleocapsid of the virus is released into the cytoplasm where replication occurs (3). The viral RNA is like a template for mRNA (3). The mRNA’s job is to translate the viral proteins and complementary RNA serves as a template for virion RNA

The norovirus is small and round. It is only 27-35 nm in diameter. The virus contains a single- stranded RNA genome. Noroviruses are divided into five genogroups, G1- G5. Of these five genogroups, only G1, G2, and G4 are known to infect humans. G2 is the most common in adult cases of gastroenteritis. 1 “Noroviruses are not enveloped and contain an outer protein capsid encapsulating an RNA genome.”2

Rabies is a fatal disease transmitted by the bite of an infected mammal. The disease travels from the saliva of the infected animal, into the wound of its victim, eventually attacking the brain and nervous system. At that time the virus get to the brain, the victim develops symptoms salivating, walking in circles, loss of appetite, fear of water, and aggression. After

Rabies is a highly infectious viral disease that can easily ruin and eventually end the lives of both humans and animals alike. Rabies comes in two forms for animals. It comes in the form of paralytic rabies, which is the kind that puts you in paralysis right from the beginning, skipping the symptoms of agitation and excitability. Rabies also appears in the form of furious rabies, which is completely different in the way that it makes the victim restless, vicious and agitated. When humans get rabies, their symptoms start out with simple headaches and fevers and later progresses to terrible things such as becoming hydrophobic because of painful throat spasms and paralysis. A definite diagnosis of rabies needs lab analysis of

The rabies virus attacks nervous tissue and appears to duplicate almost exclusively in neuronal cells. As soon as delivered through the pores and skin or mucous membrane, the virus starts replicating in the striated muscles on the wound part. The virus can reflect in muscle cells for hours or weeks, or it could migrate immediately to the nervous system through unmyelinated sensory nerve endings on the inoculation website online.

Rabies had been known about since 2000 B.C. but technology was obviously not advanced enough to try and do anything about the spread of the virus. In the year 1885, France and Belgium had become plagued with more and more cases of the rabies that the fear had soon began to become a very reasonable fear for people to have. This gave Louis Pasteur ample reason to research more about the virus.

The protective capsid helps the virus escape detection and destruction during the invasion of the host. When the virus reaches the target cell, biochemical reactions between the capsid and cell wall allow the virus to latch on and inject its genome into the cell’s interior. Once inside, the viral genetic material insinuates itself into the host’s DNA or RNA. In an efficient feat of natural bioengineering, the host cell’s genetic machinery now does the rest of the work for the virus. The cell, which had already been making copies of its own genome, now also replicates that of the virus. Coded within the viral material is the blueprint for making more copies of the viral genome. Further instructions command the production of capsids and directions for assembly of new viruses. After the host cell becomes engorged with viruses, it explodes, sending the new

Chikungunya virus is a small (about 60–70 nm-diameter), spherical, enveloped, positive-strand RNA virus (see figure 1). Early 2006, the complete sequence of a chikungunya isolate from Reunion Island was made available through NCBI/ GenBank accession no. DQ443544.1. The virion consists of an envelope and a nucleocapsid. The chikungunya virus genome is 11,805 nucleotides long and encodes for two polyproteins – the non structural polyprotein consisting of four proteins (nsP1, nsP2, nsP3 and nsP4) and the structural polyprotein consisting of five proteins (Capsid, E3, E2, 6K and E1) (see figure 2). The 5’ end of the RNA molecule is capped with a 7-methylguanosine while the 3’ end is poly-adenylated. A subgenomic positive-strand RNA referred to as 26SRNA is transcribed from a negative-stranded RNA intermediate. This RNA serves as the mRNA for the synthesis of the viral structural proteins. Alphaviruses have conserved domains that play an important role in the regulation of viral RNA synthesis. These domains are found at the 5’ and 3’ ends as

The HIV-1 virion is approximately 120 nm in diameter, roughly spherical, and is composed of two copies of a single stranded positive sense RNA enclosed by a capsid (24). The HIV-1 genome is less than 10 kb and encodes for more than nine different gene products. It encodes for 3 major structural protein genes: gag (group-specific antigen), pol (DNA polymerase), and env (Envelope), which code for major structural proteins and essential enzymes. Gag generates the mature Gag protein matrix (MA or p17), capsid (CA or p24), nucleocapsid (NC or p7), and p6, which encompass proteins for the basic infrastructure of the virus such as the inner core of the viral particle (25). Pol encodes for reverse transcriptase (RT), which enables the virus to reproduce, integrase (IN), which is necessary to integrate the viral double stranded DNA into the host genome, RNAse H, and HIV protease, which are all encapsulated in the core of the inner particle formed by the viral capsid protein p24 (25). Env encodes for glycoproteins of the outer membrane such as outer gp120 (which enables the virus to attach and fuse to cells of the host), and transmembrane gp41 that anchors the glycoprotein complex to the surface of the virion (25). Between the core and the envelope is the HIV matrix proteins which are composed of the viral protein p17 (23). HIV-1 also encodes for proteins with important regulatory elements (tat (Trans-Activator of Transcription) and rev

Because rabies is transmitted through saliva, the disease is usually brought about into the body by a bite of an animal already infected with the lyssa virus (rabies). Rabies then deposits itself into the tissue of the host (person/animal who has the virus in them), infecting the host and later multiplying. From there, the virus travels from the nerves to the muscles, then to the brain and spinal cord (Easmon paragraphs 8-9). At this point, the virus is multiplying rapidly and soon the brain is extremely affected, which causes it to malfunction and the part of the brain that controls breathing shuts down (Buncombe paragraph 8).