Foodborne Viral Diseases

Question 1

T/F: Bacteria causes more foodborne illness than viruses do

Answer 1

False. Viruses are the most common cause of foodborne illness.

Question 2

T/F: Hepatitis A outbreaks are of concern because they spread quickly and can lead to a decent number of fatalities.

Answer 2

False. Hep A is usually self limiting and most infections are asymptomatic.

Question 3

Hepatitis A accounts for ___% of hepatitis infections worldwide

Answer 3

90%

Question 4

Who/what is the reservoir for Hep A?

Answer 4

Humans are the most important. Non human primates can also possibly transmit it, but this isn’t a huge issue

Question 5

Where are you more likely to see clinical disease due to HAV?

Answer 5

In more developed countries

Question 6

How is HAV transmitted?

Answer 6

Directly via fecal-oral transmission and through a vehicle (food or water contaminated with feces).

Question 7

How long is the incubation period for HAV?

Answer 7

about 28 days

Question 8

How is HAV treated?

Answer 8

supportive care mostly, as this disease is self limiting and doesn’t kill people

Question 9

How is HAV prevented?

Answer 9

Vaccination to increase resistance and reduce the reservoir, target the vehicle with proper food handling, sewage and sanitation, and blocking transmission.

Question 10

What virus is also known as winter vomiting disease?

Answer 10

Norovirus.

Question 11

What virus is the most common cause of foodborne illness worldwide?

Answer 11

Norovirus.

Question 12

Who/what is the reservoir for Norovirus?

Answer 12

people. They excrete it through renal material and shed 18 hrs post infection, for 13-56 days.

Question 13

T/F: Once people are exposed to norovirus, they are less likely to become infected again, as they build immunity.

Answer 13

FALSE. There are various strains of this virus, and cross protection between strains is poor.

Question 14

How is norovirus transmitted?

Answer 14

Directly via fecal-oral route or through a vehicle, like contaminated food or water or fomites contaminated with feces.

Question 15

What is the incubation period of norovirus, and how long do people stay sick?

Answer 15

incubation - 12-48 hours, duration - 24-72 hours

Question 16

What are the clinical signs of noro?

Answer 16

nausea, acute onset vomiting, and watery, non-bloody diarrhea.

Question 17

What do you look for to determine if an outbreak was caused by noro?

Answer 17

mean illness duration 12-60 hrs, mean incubation 24-48 hours, more than 50% of people vomiting and no bacterial agent found.

MUST FIND ALL 4

Question 18

How is noro treated?

Answer 18

supportive care

Question 19

How is noro prevented?

Answer 19

proper food handling and preparation most important, proper sewage and water treatment, and personal hygiene and hand washing.

Question 20

T/F: Norovirus outbreaks are often small.

Answer 20

False. They are often quite large due to multiple forms of transmission, prolonged shedding, stability of the virus in the environment, and lack of cross protective immunity.

Question 21

What is the likelihood of you contacting gastroenteritis due to noro on a cruiseship?

Answer 21

less than 1%

Question 22

What virus is the most common cause of severe diarrhea in children around the world?

Answer 22

rotavirus

Question 23

When are rotavirus outbreaks typically seen?

Answer 23

in the winter

Question 24

Who/what is the reservoir for rotavirus?

Answer 24

people (through feces) and many animal species

Question 25

How is rotavirus transmitted?

Answer 25

fecal-oral transmission (moral of this class is to wash yo damn hands, ya nasties), and through vehicles like food, water, or fomites contaminated with feces.

Question 26

How long is rotavirus in the environment?

Answer 26

can last up to weeks in the enviro. makes it a problem in places like daycares

Question 27

How long is the rotavirus incubation period? How long are people usually sick for?

Answer 27

incubation: less than 48 hrs, duration: 3-7 days

Question 28

Is there a vaccine against rotavirus?

Answer 28

yes!

Question 29

How can you prevent rotavirus, aside from the vaccine?

Answer 29

wash your hands, and cook food appropriately.

Question 30

Other viral agents have a mean incubation period of what? How long is the illness?

Answer 30

variable incubation, usually 10-70 hours. lasts 2-9 days

Question 31

T/F: compared to bacterial illnesses, viral illnesses usually have more vomiting and less diarrhea, shorter duration of symptoms, and have a shorter incubation periods.

Answer 31

True.