17 - Rotavirus Flashcards
Rotavirus is primarily a problem for ______
kids under 5 years of age
T or F: Nearly every child in the world is infected with rotavirus at least once by the age of 5
T
___________ develops with each infection, so subsequent infections are less severe; adults are rarely affected
immunity
Rotavirus is transmitted via the ___________
fecal-oral route
In Canada about 1 in _ cases of gastroenteritis are caused by rotavirus
5
Effective treatments for Rotavirus include:
- oral rehydration therapy (for those already infected)
- vaccination (to prevent infection)
T or F: The USA and Canada vaccinate all children against rotavirus, and their hospitalization rates have fallen since this program was introduced
T
Canada recommends that all children be vaccinated against rotavirus between ______ weeks and _____ months
6
8
Rotavirus causes a mild to severe disease characterized by __________________________
nausea
vomiting
watery diarrhea
low-grade fever
Once a child is infected by the virus, there is an incubation period of about _________ before the symptoms appear
2
The period of illness is ___________, symptoms often start with vomiting followed by four to eight days of profuse diarrhea
acute
__________________ is more common in rotavirus infection than in most of those caused by bacterial pathogens, and is the most common cause of death related to rotavirus infection
dehydration
Rotavirus characteristics:
- RNA genome
- dsRNA
- non-enveloped virus
- genome 18,550 bp long
Rotavirus has a segmented linear ________ genome
dsRNA
The rotavirus genome contains ___ segments which code for ___ viral proteins
11
12
The viral mRNAs contain the 5’ methylated cap, but lack the ________
poly A tail
T or F: Instead the mRNAs have a 3’ consensus sequence (UGACC) that is conserved in all segments, and likely terminated translation
T
If an individual is co-infected with 2 different rotaviruses at the same time =
genetic reassortment
T or F: the rotavirus encodes for several layers of capsids and spike proteins
T
The external surface is made up of the _____ glycoprotein (yellow) and is embedded with the _____ spike attachment protein (red)
VP7
VP4
The intermediate ______ layer is shown in blue and the ______ core shell is shown in green
VP6
VP2
RNA-dependent RNA polymerase (___) and RNA capping enzyme (___) are attached to the inner surface of the VP2 shell (dsRNA)
VP1
VP3
Rotavirus replication and gene expression:
- Rotavirus comes through the plasma membrane
- Transcription and release of +RNAs
- +RNAs get translated into proteins
- genomic replication occurs inside the ER
- viral assembly occurs in the ER (core proteins get assembled around the nucleic material)
- VP6 coats it
- merges out using the VP7 and VP4 to add the second coat
- mature virions are released presumably following cell death and associated breakdown of host plasma membrane
