Is togavirus RNA or DNA?
Genome Structure: Togavirus genome is a positive-strand RNA of 11 kb (Fig. 13.4 ). In addition to the genomic RNA that encodes a polyprotein for nonstructural proteins, a subgenomic RNA is expressed that encodes a polyprotein for structural proteins.
What is the meaning of togaviridae?
Medical Definition of Togaviridae : a family of single-stranded RNA viruses that have a spherical virion about 70 nanometers in diameter and that include the causative agents of German measles and the three forms of equine encephalitis — see alphavirus, rubivirus.
How does rubella virus replicate?
Pathogenesis. Rubella virus is transmitted via respiratory droplets. Once the oral or nasopharyngeal mucosae have been infected, viral replication occurs in the upper respiratory tract and nasopharyngeal lymphoid tissue. The virus then spreads contiguously to regional lymph nodes and hematogenously to distant sites.
What are the symptoms of togavirus?
The infection is often asymptomatic or dismissed as a minor flu-like illness. Symptoms may include: fever, myalgia, arthritis, headache, and an exanthem which appears first on trunk of host and progresses to extremities. Less common symptoms include: jaundice and myocardial damage.
How does Togavirus enter cells?
The envelope has two glycoproteins, E1 and E2, embedded in a host-derived lipid bilayer. E2 is mainly responsible for host cell receptor engagement. The 11–12 kb ssRNA + genome has two protein-coding ORFs. After attachment, the virion enters the cell by endocytosis (Fig.
Is rubella virus a Togavirus?
The rubella virus, a togavirus of the genus Rubivirus, is an enveloped single-stranded RNA virus with a single serotype that does not cross-react with other togaviruses. Humans are the only known host, with seasonal epidemics occurring every 5-9 years over a worldwide distribution.
How do you get a Togavirus?
The alphaviruses are transmitted to humans by an arthropod vector, usually mosquitoes. Alphavirus infections usually occur during warm weather months when mosquitoes are more active and prevalent. Anyone can be infected, but young children and elderly are generally most susceptible to alphavirus infection.
How is Togavirus treated?
Treatment for togavirus infections is generally supportive in order to manage symptoms or complications. An effective measure in preventing rubella is through childhood immunizations using the MMR (Measles, Mumps Rubella) vaccine. There are no human vaccines available for the prevention of the alphavirus diseases.