Picornaviruses Flashcards
What are picornaviruses?
- comes from pico- (small) and RNA genome
- class IV virus: Linear, +ssRNA genome
- broad host range: mammals, Bords, Fish
Poliovirus is the cause of which disease? and what are the symptoms of this disease?
Disease is poliomyelitis
- virus affects CNS: footdrop, paralysis can weaken chest muscles needed for breathing
Poliovirus is the cause of which disease? and what are the symptoms of this disease?
Disease is poliomyelitis
- virus affects CNS: footdrop, paralysis can weaken chest muscles needed for breathing
What are the mechanisms that lead to disease from poliovirus?
- oral-fecal virus
- replicates in mucosal cells
- spread to nerve cells is a cause of paralysis, which does not help with transmission
- b/c it shed in feces, higher rates of infection in children, poor hygiene, unprimed immune systems
Pre-vaccine what were the stats of Poliovirus?
- 70% of infections are asymptomatic
- affects mostly children under 5
- 1 in 200 infections leads to paralysis
- 5-10% of paralyzed die due to paralysis of chest muscles- thus treatment with iron lungs
What type of vaccine did Jonas Salk produce against Polio?
- inactivated poliovirus vaccine
What kind of vaccine did Albert Sabin produce?
- oral vaccine, attenuated,
- still used where disease is endemic
What scientific advancements where necessary to make both polio vaccine possible?
- both vaccines possible with advances in animal cell cultures
What is Henrietta Lacks consensual contribution to science?
- got treatment for cervical cancer, then cells were collected and used for research without her permission
What is special about the genomes in class IV (+ssRNA) viruses?
- the genome functions as mRNA, the message
What are the steps involved in Class IV virus infection?
1) mRNA (genome) instructs for the construction of proteins
2) once enough protein is made, mRNA replicates
3) (+) strands of genome made
4) proteins then made from (+) strand genome
5) proteins and +RNA construct new virions
