Download Norovirus and Its Importance in School Cafeterias

Norovirus and its
Importance in School
Cafeterias
Dr. Ben Chapman and Katie Overbey
North Carolina State University
March 26, 2015
What is Norovirus?
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•
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Virus that causes
gastrointestinal (GI)
illness around the world
Leading cause of GI
illness
You may also know it as:
Norowalk virus
o Winter vomiting disease
o Cruise ship virus
o Stomach flu*
o
http://www.dailymail.co.uk/news/article-2253996/Around150-passengers-hit-norovirus-Queen-Mary-2-luxuryChristmas-cruise.html
Symptoms
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Symptoms usually resolve on their own after
2-3 days, but may be more severe in young
children, the elderly and immunocompromised
people
After becoming infected with the virus, it takes
24-48 hours to show symptoms
Norovirus Shedding
Asymptomatic
Vomiting/diarhea
Virus particles shed even up to two
weeks
Atmar et al. 2008. Emerg Infect Dis. 14(10):1553-7.
About
Norovirus
Infection
•
Can infect persons
of all ages
•
Takes a very small
amount of virus to
cause infection
(Patel, Hall, Vinjé, &
Parashar, 2009)
Treatment
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•
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No vaccine or drug for
treatment is available,
symptoms usually go away
on their own
Antibiotics will not work
Hydration is recommended,
and in some severe cases
an IV may be necessary
Source: CDC
http://www.rgvfit.net/proper-hydration-tips-trainingphysical-events/
Recent outbreaks
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March 2014: Elementary and
High School in Asheville, NC
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o
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More than 160 students ill
Appeared to have spread from the
Elementary to the High School
February 2015: Longwood
University in Farmville, VA
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Three dozen confirmed cases
Thought to have spread from
Hampden-Sydney College where there
were about 300 cases
How common is Norovirus?
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About 1 in 15 Americans
will get it each year
5.5 million food related
cases in the US each year
Second leading cause of
food related
hospitalizations
(Scallan et al., 2011; CDC, 2013)
Transmission of Norovirus
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Can spread easily from
person to person
o
•
Fecal- oral route
Contaminated water or
food
o
Contamination originates from
human source
(Anderson et al.,
2001; Maunula et al.,
Transmission of Norovirus
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Touching infected
surfaces
o
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Can survive on surfaces for
up to 2 weeks and in water
for up to 2 months
From aerosolized
particles
(Lopman et al., 2004)
http://www.cidd.psu.edu/research/synopses/social-contact-network-disease-transmission
Norovirus on Surfaces
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Norovirus is extremely hardy
and can survive on surfaces
for up to 2 weeks
https://followtheoutbreak.files.wordpress.com/2014/09/doorknob.jpg?w=2560&h=1200&crop=1
Surface disinfection is
crucial
(Lopman et al., 2004)
http://onmilwaukee.com/images/articles/sc/schoolcafeteria/schoolcafeteria
_story1.jpg
Relevance of Norovirus in
School Settings
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Highly infectious
Common food lines and
eating areas can lead to
increased transmission
Lives on surfaces for
long periods of time
(Lee & Greig, 2010)
Prevention Strategies
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Exclusion of sick food handlers
o
o
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People may be infectious even if they don’t show symptoms
If an employee is showing symptoms, they are infectious
and can remain infectious for up to 72 hours after
symptoms subside
It is important that employees who have been
sick are excluded from food preparation while
they are ill and 72 hours after getting better
(Barrabeig et al., 2010)
Food Handling Precautions
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If you’re sick- do not
prepare food!
If you think food has
come in contact with
norovoris- throw it out!
Cleaning To Prevent Norovirus
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Proper hand washing is
crucial
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Hand sanitizer does not work
http://www.naturescornernaturalmarket.com/wp-content/uploads/2013/07/hand-sanitizer.
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On surfaces, only a bleach
solution will work
Products like Lysol or Clorox wipes
are not effective
o Other sanitizer, like quaternary
ammonium
are not
(Hall et
al., 2011; compounds,
Liu, Yuen, Hsiao,
Jaykus, & Moe, 2010)
recommended either
o
Cleaning To Prevent
Norovirus
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Use appropriate personal
protection
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Disposable mask
Disposable gloves
If there is a vomit incident,
it must be properly
cleaned first
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Use of absorbent powder
(Hall et al., 2011)
Preparing a Bleach Solution
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Need to prepare a fresh
bleach solution
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No more than 24 hours old
Need between a 1:10 and
1:50 dilution
o
o
Correct concentration is critical
Because of the way bleach is
formulated if there is too little or too
much it will not work
(Hall et al., 2011)
Cleaning to Prevent
Norovirus
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Bleach needs to have
appropriate contact time with
surface to disinfect properly
o
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Current recommendation is about 4
minutes
Radius
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When a vomiting incident occurs,
particles can spread between 3 and 15
feet around the original site
Important to clean around the area
(Tung, 2013)
Summary
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Only takes 1-10 virus particles to cause
illness
Billions in each poop or vomit event
Shedding lasts for 10+ days
Dr. Ben Chapman
[email protected]
Follow me on twitter @benjaminchapman
919 809 3205
foodsafetyinfosheets.org
foodsafetytalk.com
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