Norovirus Flashcards
What is the most common cause of gastroenteritis in England and Wales?
Norovirus
Norovirus contains double-stranded RNA. True or false?
False - ssRNA
Norovirus is a non-enveloped virion. True or false?
True
Does norovirus have a high or low infectious dose and what does this mean?
Low infectious dose - don’t need to acquire a lot of the virus for an infection to be caused
Norovirus has only one variant. True or false?
False - it is variable
Is there a vaccine that protects against norovirus?
No
What are the symptoms of norovirus?
Often start with sudden onset of nausea followed by projectile vomiting and watery diarrhoea
headaches
myalgias and malaise
low-grade fever
abdominal cramps
gastroenteritis develops 24-48h after consumption of contaminated food/water/contact with infected individual
episodes are short-lived often lasting 24-72h
How is norovirus transmitted?
Person-person
aerosol exposure (droplets)
faecal-oral route
Norovirus is highly contagious. True or false?
True - infection requires fewer than 10 virions
Norovirus is extremely stable in the environment. True or false?
True
Viral shedding may occur for up to how many weeks after infection?
3
Can recurrent infection of norovirus happen?
Yes because of the diversity of strains and lack of long-term immunity
Why can infection with norovirus lead to lactose intolerance?
Because virus infects the brush border of the small intestine, the machinery that absorbs lactose is damaged
The most effective prevention of norovirus is through hand washing. True or false?
True
Infection damages microvilli of intestine. True or false?
True
People infected with norovirus should keep themselves isolated for 48 hours. True or false?
True
Closure of hospital wards usually takes place when there is an outbreak. True or false?
True
There is a specific medication for treatment of norovirus. True or false?
False
What are the “danger symptoms” of norovirus?
Blood in stools
Mucus in diarrhoea
Symptoms of severe dehydration - weakness, confusion, rapid HR
Oral rehydration is important. True or false?
True
Loperamide can be given for acute diarrhoea. What is the mode of action?
Binds to opiate receptor in gut wall - reduces propulsive peristalsis and increasing intestinal transit time
Rotavirus and norovirus are the same thing. True or false?
False
Rotavirus is the most common cause of gastroenteritis in children. True or false?
True
Norovirus is the most common cause of gastroenteritis in adults. True or false?
True
What are the referral criteria for norovirus?
Any “dangerous symptoms”
pregnancy
>1 day symptom duration in children <1 year
>2 day symptom duration in children <3 years and elderly
>3 day symptom duration in older children and adults
diarrhoea associated with severe vomiting and fever
