GI Viruses Flashcards
Learn about the GI viruses
There are five Important viruses that cause gastroenteritis, What are they?
(RAANE) • Rotavirus • Adenovirus • Astrovirus • Norovirus • Enterovirus
Out of the Important viruses that cause gastroenteritis, Which 2 predominantly cause acute gastroenteritis?
(RoAd)
Rotavirus and Adenovirus are predominantly the cause of acute gastroenteritis
What is gastro-enteritis?
Inflammation of the gastrointestinal tract – the stomach and small intestine.
Ture or False:
Gastroenteritis is always caused by viruses.
False
Gastroenteritis could be bacterial, viral or parasitic
How many children die from gastroenteritis per year?
4-6 million
What is meant by Reovirus?
(R) Respiratory (E) Enteric (O)Orphan viruses
What kind of virus is Reovirus?
Reovirus is a Naked (Class III) linear ds RNA in 10-12 segments arranged into a icosahedral capsid
Reovirus is a type of _____ virus.
Rotavirus
True of False:
In Rotavirus there are three concentric viral protein shells (VP 2, 6, 7) enclose 11 gene segments
True
In Rotavirus on the outer shell which two viral proteins define the serotype and provide protection?
VP7 and VP4
5 serotypes of rotavirus _____ accounts for 90% of isolates from children younger than 5 years. Of these, the ___ strain accounted for more than 75% of isolates
5 serotypes of rotavirus (G1-4, G9) accounts for 90% of isolates from children younger than 5 years. Of these, the G1 strain accounted for more than 75% of isolates
Which of the following are methods of contamination of Rotavirus;
– Needle sharing
– Sexual Intercourse
– Contamination occurs through water or food
– Contamination is possible through aerosols
– Contamination occurs through water or food
and
– Contamination is possible through aerosols
True of False:
Rotavirus is very stable at room temperature, can survive detergents, freezing and thawing as well as wide range pH (3.5- 10),
True
How many serotypes of Rotavirus are there?
(15): Six are based on antibodies to VP7 (G type=Glycoprotein) divided into A and B, nine based on VP4 (P type=Protease) outer capsid proteins
Rotavirus has an Incubation of ___ hours then causes Diarrhea and vomiting.
Rotavirus has an Incubation of 48 hours then causes Diarrhea and vomiting.
The main cause of mortality in rotavirus is _____, due to Diarrhea.
Dehydration
Antibodies against __ and __ probably important for protection
Antibodies against VP7 and VP4 probably important for protection
True or False:
First infection usually does NOT lead to permanent immunity so a less severe reinfection can occur at any age.
True
Which of the following are possible Treatment, control and prevention of rotavirus.
– Symptomatic treatment: rehydration with a solution containing balanced electrolytes and salt
– Antiemetics for vomiting children older than 6 months
– Control by hygiene
– Vaccine available since 2007 for infants
All of them
What are the main two vaccines for Rotavirus?
RotaTeq (Merck) and ROTARIX (GSK)
What kind of vaccine is Rotateq (Merck) and when should it be administered?
Live oral pentavalent vaccine, RV5 contains five live attenuated strains 3-doses schedule (age 2, 4, 6 months, minimum age of 1st dose is 6 weeks
What kind of vaccine is ROTARIX (GSK) and when should it be administered?
Live oral monovalent vaccine. RV1 contains one live attenuated strains Two doses: 3 and 4 months
Norovirus is a subgroup (genus) within what viral family?
Caliciviruses
What kind of virus is Astrovirus?
A nonenveloped (Class II) ds RNA virus in a single strand.
Astrovirus is known to cause ___ (more or less) severe gastroenteritis than that caused by other enteric pathogens
Less
In immunosuppressed adults, what virus is reportedly the most common viral agent associated with diarrhea?
Astroviruses are reportedly the most common viral agent associated with diarrhea in immunosuppressed adults
What is the structure of Norovirus (Calicivirus)?
Round shaped non-enveloped (Class IV) ss(+) RNA viruses with icosahedral symmetry that contains a single capsid protein
True or False:
Calciviruses can’t be grown in cell culture but Norwalk viruses can.
False
Calciviruses can be grown in cell culture but not Norwalk (Noro) viruses.
Norovirus and Rotovirus are similar in that they have a ____ ____ Infectious dose?
very low
True or False:
Norovirus and Rotovirus are similar in their stability except norovirus is more resilient to chlorine.
True
How does Norovirus cause Diarrhea?
Shortening of microvilli, presence of cytoplasmic vacuoles and disturbance of water absorption and loss of ions resulting in watery diarrhea
What is the incubation period of Norovirus and how long does it last?
12 hours to 4 days Symptoms usually resolve within 24-48 hours after manifestation.
Can recurrent infections occur with Norovirus?
Yes, Recurrent infections can occur throughout life because of the diversity of norovirus strains and lack of cross strain or long term immunity
True or False:
Treatment and prevention of Noroviruses can be treated completely with Bismuth subsalicylate
False
No specific antiviral therapy, but Bismuth subsalicylate may reduce the severity.
True or False:
Adenovirus can cause a different infection by infecting different areas of the body.
True
What serotypes of Adenovirus cause Gastroenteritis?
serotype 40 and 42 a.k.a. group F
