Giardiasis

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Giardiasis
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Giardiasis

• Giardiasis is a diarrheal illness caused by
  Giardia intestinalis (also known as Giardia
  lamblia)
• The parasite is passed in the stool of an
  infected person or animal (both cysts
  trophozoites)
• The parasite is protected by an outer shell that
  allows it to survive outside the body and in the
  environment for long periods of time
• During the past 2 decades, Giardia has become
  recognized as one of the most common causes of
  waterborne disease (drinking and recreational) in
  humans in the United States
• Very contagious

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Symptoms

• Symptoms include
• diarrhea
• loose or watery stool
• foul-smelling stool
• stomach cramps
• upset stomach
• weight loss
• dehydration
• Some may be asymptomatic

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Incubation Period Duration

• Incubation period
• Symptoms generally begin 1-2 weeks after being
  infected
• Duration
• Healthy persons, symptoms may last 2-6 weeks

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How is Giardia spread?

• Swallowing recreational water contaminated with
  Giardia
• Eating uncooked food contaminated with Giardia
• Possibly found in soil, food, water, or surfaces
  contaminated with Giardia

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Who is at risk?

• Everyone
• Persons at increased risk include
• child care workers
• children who attend day care centers
• international travelers
• hikers, campers, swimmers
• people drinking or accidentally swallowing
  untreated water

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Treatment

• Several prescription drugs are available
• Consult with your health care provider
• Giardia can infect all people
• Young children pregnant women may be more
  susceptible
• Drink plenty of fluids while ill

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Prevention

• Practice good hygiene
• Wash hands thoroughly with soap and water
• after using the toilet
• before handling or eating food
• after every diaper change
• Protect others by not swimming if experiencing
  diarrhea

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Prevention

• Avoid food that might be contaminated
• Wash and/or peel all raw vegetables and fruits
  before eating
• Use uncontaminated water to wash all food that is
  to be eaten raw
• Avoid eating uncooked foods when traveling in
  countries with minimal water treatment and
  sanitation systems 
• Avoid fecal exposure during sex

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Prevention

• Avoid water that might be contaminated
• Avoid swallowing recreational water
• Avoid drinking untreated water from ponds and
  streams
• Avoid using ice or drinking untreated water when
  traveling in countries where the water supply
  might be unsafe
• If you are unable to avoid drinking or using
  water that might be contaminated, then treat the
  water yourself by
• Heating the water to a rolling boil for at least
  1 minute
• You can pass Giardia in your stool and
  contaminate water for several weeks after your
  symptoms have ended

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Infectious Diarrhea in Tourists Staying in a
Resort HotelEID January-February 1999, 5 (1)
168-171

• British residents ill while staying at a hotel in
  Greece
• 6 lab confirmed cases of Giardia
• All stayed in the same hotel
• School sought advice about excluding a child with
  diarrhea
• 6 patients reported that many hotel guest were
  ill

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Resort Hotel OutbreakEID January-February 1999,
5 (1) 168-171

• British guests arrived at the hotel between May
  22 and June 9 1997
• Questionnaire administered by phone
• 86 booking groups
• 51 groups 239 persons interviewed
• 224 ill while on holiday or within a few days of
  return
• 95 diarrhea
• Median duration of 13 days
• 82 stomach cramps
• 64 vomiting
• Median duration of 1 day
• 35 groups- 138 persons could not be contacted

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Resort Hotel Outbreak EID January-February 1999,
5 (1) 168-171

• 224 ill
• DEFINITE cases - lab confirmed
• 70 (31)
• PROBABLE cases no pathogen identified but had
  diarrhea lasting 4 or more days
• 107 (48)
• POSSIBLE cases no pathogen identified but had
  diarrhea lasting less than 4 days

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Table 1 Pathogens identified in DEFINITE cases
Pathogen No. of definite casesa ()
Giardia lamblia 58 (83)
Cryptosporidium parvum 11 (16)
Campylobacter spp. 4 (6)
Salmonella spp. 3 (4)
Entamoeba histolytica 2 (3)
Rotavirus 1 (1)
Sum exceeds 70 because of co-infections
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Figure 1. Epidemic curve for diarrhea, by
category of case
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Figure 2. Interval between arrival at hotel and
onset of illness (vomiting or diarrhea), by
category of case
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Resort Hotel Outbreak EID January-February 1999,
5 (1) 168-171

• Telephone interviews 54 reports
• 32 (59) identified problems with food
• Tasted strange
• Inadequately cooked or heated
• Left out uncovered
• 27 (50) identified problems with room water
• Sewage smell
• Discoloration (around June 4)
• 7 (13) identified problems with drinks
  reconstituted with tap water

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Resort Hotel Outbreak EID January-February 1999,
5 (1) 168-171

• Significantly associated with illness
• Consumption of reconstituted orange juice
• Consumption of raw vegetables and salads
• Reports of problems with water in the hotel room

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Resort Hotel Outbreak EID January-February 1999,
5 (1) 168-171

• 2 Principal illnesses due to sewage contamination
  of the water supply
• Viral gastroenteritis outbreak
• Giardiasis outbreak

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Resort Hotel Outbreak EID January-February 1999,
5 (1) 168-171

• Outbreak
• Point-source
• Lab confirmation
• 129 guests reported that their room water smelled
  of sewage or was discolored around June 4 (mostly
  from definite cases)
• All avoided tap water
• a. Consumption of reconstituted orange juice
• Water supply was chlorinated but not filtered at
  certain points within the hotel