Rabies Virus

What is The Structure of Rabies?

Rabies virus (RABV), a negative-stranded RNA virus, belongs to the genus Lyssavirus of the Rhabdoviridae family ^[1]. RABV is characteristic by rod- or bullet-shaped rhabdovirus virion observed through electron microscopy (Figure 1). The nucleocapsid is spirally symmetrical, the surface has an envelope, and it contains single-stranded RNA. The virus particle has a capsule outside and a nucleoprotein shell inside. The outermost layer of the capsule has many fibrils composed of glycoproteins, which are arranged neatly. This protrusion is antigenic and can stimulate the body to produce neutralizing antibodies.

Figure 1. The structure of RABV

*This diagram is derived from the publication published on Annu Rev Virol ^[2]

All rhabdoviruses encode five structural proteins: nucleoprotein (N), phosphoprotein (P), matrix protein (M), glycoprotein (G), and an RNA-directed RNA polymerase (L). RABV genome consists only of these five ^[3]. N encapsulates the RNA genome, forming a tightly wound N-RNA complex known as a ribonucleoprotein (RNP) ^[4]. The RNP is condensed into a helical nucleocapsid (NC) with L and P. P is a noncatalytic cofactor for the polymerase L. M surrounds the NC, forming a bridge between the NC and the viral envelope. G, which is trimeric and interacts at its cytoplasmic side with M, is the only protein exposed on the surface of the rhabdovirus envelope and is the sole ligand for the cellular receptor.

See All Related Proteins of Rabies-Virus

How to Transmit Rabies to Animal or Person?

Rabies infection is caused by the rabies virus. The virus is spread through the saliva of infected animals. Infected animals can spread the virus by biting another animal or a person. Any mammal (an animal that suckles its young) can transmit the rabies virus. The animals most likely to transmit the rabies virus to people include: cat, cow, dog, ferret, goat, horse, bat, beaver, coyote, fox, monkey, raccoon, skunk and woodchuck.

In rare cases, rabies can be spread when infected saliva gets into an open wound or the mucous membranes, such as the mouth or eyes. This could occur if an infected animal were to lick an open cut on your skin.

What is Pathogenesis of Rabies?

Accumulating evidences have proved that the pathogenesis rabies can be divided into three stages during the incubation period and the onset period without viremia.

• Breeding period in local tissues

  After the virus invades from the bite site, it accumulates and reproduces at the nerve fibers of the striated muscle spindle receptor of the wound, and then invades nearby peripheral nerves. The interval from local wound to invasion of peripheral nerves is generally within 3 days, and some people think that the virus can stay in the invasion site for 2 weeks or even longer.

• Invasion of the central nervous system

  The virus spreads centripetally along the axonal plasma of the peripheral nerve at a speed of about 3 mm/h. After arriving the dorsal root ganglion, the virus multiplies in it, and then invades the spinal cord and the entire central nervous system, mainly invading neurons in the brain and cerebellum.

• Period of diffusion to various organs

  The virus spreads centrifugally from the central nervous system to the peripheral nerves, invading various tissues and organs, especially the salivary nucleus, glossopharyngeal nucleus, and hypoglossal nucleus.

What are The Symptoms of Rabies?

The first symptoms of rabies may be very similar to those of the flu and may last for days. Later signs and symptoms may include: fever, headache, nausea, vomiting, agitation, anxiety, confusion, hyperactivity, difficulty swallowing, excessive salivation, fear brought on by attempts to drink fluids because of difficulty swallowing water, hallucinations, insomnia and partial paralysis.

How to Prevent Yourself from Rabies?

As you know, rabies is the acute infectious disease with the highest human fatality rate so far, and is preventable and incurable. So the prevention of rabies cannot be delayed. You can take the following measures to prevent yourself form rabies:

• Vaccinate your pets. Cats, dogs and ferrets can be vaccinated against rabies. You must vaccinate your pet every year to ensure the health of your pet and the safety of its owner.
• Keep your pets inside and supervise them when outside. This will help keep your pets from coming in contact with wild animals.
• Report stray animals to local authorities. Call your local animal control officials to report stray dogs and cats.
• Consider the rabies vaccine if you're traveling. If you're traveling to a country where rabies is common and you'll be there for an extended period of time, ask your doctor whether you should receive the rabies vaccine.

Related Protein Reagents

References:

[1] Kuzmin IV, Tordo N. 2012. Genus Lyssavirus. In Rhabdoviruses: Molecular Taxonomy, Evolution, Genomics, Ecology, Host-Vector Interactions, Cytopathology and Control, ed. RG Dietzgen, IV Kuzmin, pp. 37–58. Norfolk, UK: Caister Acad.

[2] Benjamin M. Davis, Glenn F. Rall, et al. Everything You Always Wanted to Know About Rabies Virus (But Were Afraid to Ask) [J]. Annu Rev Virol. 2015.

[3] Dietzgen RG, Kuzmin IV. 2012. Taxonomy of rhabdoviruses. In Rhabdoviruses: Molecular Taxonomy, Evolution, Genomics, Ecology, Host-Vector Interactions, Cytopathology and Control, ed. RG Dietzgen, IV Kuzmin, pp. 13–22. Norfolk, UK: Caister Acad.

[4] Rahmeh AA, Schenk AD, et al. Molecular architecture of the vesicular stomatitis virus RNA polymerase [J]. PNAS. 2010, 107:20075–80.