Giardiasis (Gastroenteritis) in Grand Rapids, Michigan

Giardiasis is a type of gastroenteritis (often called “gastro” or “stomach bug”) caused by a microscopic parasite called Giardia duodenalis. This parasite lives in the intestines and is passed in the stool (feces) of infected people and animals.

In Grand Rapids and across West Michigan, giardiasis is most often linked to:

  • Contact in childcare settings
  • Drinking or swallowing untreated water from rivers, streams, or lakes (including the Grand River and nearby inland lakes)
  • Poor hand hygiene after using the bathroom or changing diapers

The infection can affect anyone, but it is more common in:

  • Infants and young children
  • Adults aged 20–40 years
  • People who work in or attend childcare centers
  • Campers, hikers, and people who drink untreated surface water

How Giardiasis Spreads in Grand Rapids

Giardia parasites are found worldwide, including in Michigan. They are more common in places or situations with poor sanitation or hygiene.

In the Grand Rapids area, giardiasis can spread:

1. In Childcare Centers and Schools

Giardiasis spreads easily where:

  • Children are not toilet trained
  • Diapers are changed frequently
  • Handwashing is inconsistent

Contaminated hands can spread Giardia to:

  • Toys, tables, and other surfaces
  • Food and drinks
  • Other children and staff

2. From Animals

Giardia parasites can be found in:

  • Wild animals (beavers, muskrats, deer, etc.)
  • Farm animals around West Michigan
  • Household pets (especially puppies and kittens)

Handling infected animals or cleaning up their stool without proper handwashing can lead to infection.

3. Through Water – A Key Issue in Michigan

Because Michigan is part of the Great Lakes region and Kent County has many rivers, streams, and lakes, waterborne giardiasis is an important concern.

Giardia can be spread by:

  • Drinking untreated water directly from lakes, rivers, or streams
  • Swallowing contaminated water while swimming in:
    • Community pools and splash pads
    • Lakes and rivers around Grand Rapids
    • Hot tubs and spas with poor sanitation

People who have had giardiasis should not use swimming pools, hot tubs, or splash pads until at least one week after their symptoms have completely stopped, and they should shower thoroughly before swimming again.

Symptoms of Giardiasis

Symptoms usually start 7–10 days after infection but can appear as early as 3 days or as late as 3 weeks. In some people, symptoms can become long-lasting (chronic).

Common symptoms include:

  • Diarrhea (may be watery, foul-smelling, and frequent)
  • Steatorrhea – pale, bulky, greasy stools that may float (due to poor fat absorption)
  • Abdominal cramps or bloating
  • Gas (flatulence)
  • Nausea (sometimes vomiting)
  • Fatigue and low energy
  • Weight loss or poor weight gain in children

Some people infected with Giardia have no symptoms at all but can still pass the parasite in their stool and infect others.

When to See a Doctor in Grand Rapids

Contact a doctor or clinic in Grand Rapids if you or your child has:

  • Diarrhea lasting more than a few days
  • Greasy, foul-smelling stools
  • Stomach cramps, bloating, and gas that do not improve
  • Unexplained weight loss or fatigue
  • Symptoms after drinking untreated water while camping, hiking, or swimming

Local options include:

  • Primary care providers and pediatricians affiliated with Corewell Health (Spectrum Health), Trinity Health Grand Rapids, Metro Health – University of Michigan Health, and Mercy Health
  • Urgent care centers across Grand Rapids
  • The Kent County Health Department or Grand Rapids Public Health for guidance on infectious diseases and reporting

If you are very unwell, dehydrated, or cannot keep fluids down, seek urgent care or visit a local emergency department.

How Giardiasis Is Diagnosed

Your doctor will usually:

  1. Ask about your symptoms, recent travel, swimming, camping, or childcare exposure.
  2. Arrange a stool (feces) test to look for Giardia parasites or their antigens.
  3. Sometimes request more than one stool sample on different days, as the parasite may not show up in every sample.

If the stool test confirms giardiasis, your doctor will:

  • Prescribe appropriate anti-parasitic medication
  • Advise on hydration, diet, and preventing spread to others
  • Report the infection to public health authorities, such as the Kent County Health Department, as required for infectious disease monitoring in Michigan

Treatment of Giardiasis

Giardiasis is usually treated with prescription medications that kill the parasite. Your doctor will choose the best medicine for you or your child.

Treatment often includes:

  • Anti-parasitic medication (taken for several days)
  • Fluids and electrolytes to prevent or treat dehydration
  • A bland diet while your stomach recovers (avoiding very fatty, spicy, or sugary foods)

Most people improve within a few days of starting treatment, but bowel habits may take longer to fully normalize.

Preventing the Spread of Giardiasis in Grand Rapids

Preventing giardiasis is especially important in community settings, childcare centers, and during outdoor activities common in Michigan’s warmer months.

Stay Home Until Symptoms Stop

To prevent spreading Giardia:

  • Children with giardiasis should stay home from school or childcare until diarrhea has completely stopped.
  • Adults should stay home from work while they have diarrhea, especially if they are:
    • Food handlers (restaurants, cafeterias, catering, food processing)
    • Healthcare workers (hospitals, clinics, nursing homes)
    • Childcare workers or teachers

Practice Excellent Hand Hygiene

Wash hands thoroughly:

  • After using the toilet
  • After changing diapers or helping a child in the bathroom
  • After handling animals or cleaning up animal stool
  • Before preparing food
  • Before eating or feeding a child

Use soap and warm water, scrubbing for at least 20 seconds, and dry hands with a clean towel or air dryer.

Clean Bathrooms and Toilets Thoroughly

  • Clean and disinfect toilet seats, flush handles, faucets, and bathroom surfaces regularly.
  • In homes with an infected person, clean bathrooms daily during illness.
  • Use a disinfectant cleaner according to label instructions.

Do Not Drink Untreated Water

In Michigan’s Great Lakes and inland lakes region:

  • Do not drink untreated water from rivers, streams, or lakes, even if it looks clean.
  • When camping, hiking, or using a cottage:
    • Boil water for at least 1 minute (3 minutes at higher elevations), or
    • Use a filter that removes parasites like Giardia, or
    • Use water purification tablets specifically labeled for protozoa.

Safe Swimming Practices

To protect others:

  • Do not swim in public pools, hot tubs, splash pads, lakes, or rivers while you have diarrhea.
  • After giardiasis, avoid swimming for at least one week after all symptoms have stopped.
  • Shower thoroughly with soap before entering a pool.
  • Do not swallow pool or lake water.

Parents should:

  • Take children on regular bathroom breaks while swimming.
  • Change diapers in designated changing areas, not poolside.
  • Wash their hands after every diaper change.

Food Safety

If you have or recently had giardiasis:

  • Do not prepare or handle food for other people until diarrhea has completely stopped.
  • Always wash hands before cooking or eating.
  • Wash fruits and vegetables under running water.
  • Avoid cross-contamination between raw and ready-to-eat foods.

Avoid Sharing Personal Items

Do not share:

  • Towels
  • Washcloths
  • Bath sponges

with anyone who has giardiasis.

Local Public Health and Support Resources

If you live in the Grand Rapids area and have questions about giardiasis, prevention, or local outbreaks, you can contact:

  • Kent County Health Department – for information on infectious diseases, water safety, and community health resources
  • Grand Rapids Public Health – for local health education and support
  • Your primary care provider or pediatrician through Corewell Health (Spectrum Health), Trinity Health Grand Rapids, Metro Health, or Mercy Health

In a medical emergency (severe dehydration, confusion, or inability to keep fluids down), call 911 or go to the nearest emergency department.

Key Points About Giardiasis in Grand Rapids

  • Giardia is a parasite found worldwide and can be present in untreated water, animals, and contaminated surfaces.
  • Giardiasis is more common in infants, children, and adults aged 20–40 years, and in childcare and outdoor recreation settings.
  • Some people with Giardia have no symptoms but can still spread the infection.
  • Diagnosis is made by stool testing, and effective treatment is available from your doctor.
  • Prevent spread by:
    • Keeping children home from school or childcare until diarrhea has stopped
    • Staying home from work if you handle food, work in healthcare, or in childcare
    • Washing hands thoroughly and often
    • Avoiding untreated water and not swimming while sick or shortly after illness

By following good hygiene, safe water practices, and local public health guidance, residents of Grand Rapids can significantly reduce the risk of giardiasis in our community.