Infectious Colitis: Symptoms, Treatments, and More

Infectious colitis is a contagious illness caused by an infection in the colon (large intestine). It can develop due to a virus, bacterium, or parasite and most often comes from contaminated food or water.

Why is Infectious Colitis Contagious?

Infectious colitis (an inflamed colon) is contagious because it’s caused by bacteria, viruses, and parasites. These microorganisms are easily spread through contact with infected body fluids, contaminated food or water, and feces.

Though less common, infectious colitis could be spread by touching surfaces or objects that are contaminated, like a toothbrush.

There are several types of colitis, including ulcerative colitis (an autoimmune disease) and allergic colitis (caused by an allergy to specific proteins). Of the varying types, infectious colitis is the only one that’s contagious.

Bacterial Causes

A large number of cases of infectious colitis are caused by bacteria, specifically food-borne bacteria. Common causes of bacterial colitis include:

Viral Causes

Infectious colitis can also be caused by viruses like the cytomegalovirus (CMV). This is a common virus that can be spread through bodily fluids like saliva, blood, urine, semen, and vaginal fluids. It can cause CMV colitis, resulting in inflammation of the stomach and intestines.

Aside from CMV, other viruses that can cause colitis include:

• Adenovirus, which causes cold-like symptoms
• Norovirus, which causes vomiting and diarrhea
• Rotavirus, which causes severe, watery diarrhea in children and infants

Parasitic Causes

One common example of a parasite that can cause colitis is Entamoeba histolytica. Another is the parasite Trypanosoma cruzi (T. cruzi), which leads to Chagas disease, most common in Central America and South America.

Many parasitic infections can be spread through water or food contaminated by infected stools, close personal contact through the rectal area or mouth, or contaminated fertilizer made from human waste.

In the case of T. cruzi, the parasite is most commonly spread through the bite and fecal matter of an insect, the triatomine bug.

How Will I Know I Have Infectious Colitis?

Symptoms of infectious colitis can vary depending on the underlying cause. They can include:

• Bloating, abdominal pain, cramping
• Bloody or mucus-filled bowel movements
• Dehydration
• Diarrhea
• Headaches
• Fever
• Vomiting

Should I See My Healthcare Provider?

Self-care at home may be enough for a mild case of infectious colitis. However, you should see a healthcare provider if you have moderate to severe symptoms, a fever, blood in your stool, or severe abdominal pain.

Infants, older adults, and people with a weak immune system should seek medical care even if they have mild symptoms.

Without treatment, complications can develop. Depending on the microorganism causing the condition, you could develop health problems such as:

• Ruptured colon
• Bleeding
• Joint inflammation
• Brain inflammation (encephalitis)
• Low blood sugar
• Skin conditions
• Extreme colon enlargement (toxic megacolon)

How Is Infectious Colitis Diagnosed?

Your healthcare provider will perform a thorough screening, including your medical history and physical examination. They may ask if you’ve been using antibiotics and whether you have traveled recently, especially to areas that do not have a clean water supply. Additionally, you’ll be questioned about whether you have been admitted to a hospital.

Beyond this, your provider will determine if you’re dehydrated and take a stool sample to see if you have any viruses, parasites, or bacteria in your system.

If the stool sample is inconclusive, your healthcare provider may perform additional diagnostic tests, such as:

• Complete blood count
• Bacteria culture test
• Diagnostic imaging like X-rays or CT scans
• Total protein test
• Colonoscopy (to examine the inside of the colon)

People with sepsis (a life-threatening condition caused by an infection), older adults, and individuals who are immunocompromised may also need diagnostic imaging.

What Treatments Will I Need?

It’s important to focus on staying hydrated. Your healthcare provider may prescribe an oral rehydration solution to replenish electrolytes lost due to diarrhea and vomiting. In severe cases, they may administer fluids through an IV (an intravenous drip).

If you have a bacterial infection, your healthcare provider will likely prescribe antibiotics. The dosage and medication will depend on the infection and your overall health.

Treatment for parasitic colitis will generally involve hydrating as well as a prescription. In more serious cases, a surgical procedure on the colon, rectum, or surrounding areas may be needed.

Consult with your provider to review the best course of treatment and care as you recover.

Is Infectious Colitis a Chronic Condition?

Bacterial, viral, and parasitic colitis can be cured when the appropriate measures are taken. Infectious colitis is not a chronic condition that needs to be managed like Crohn’s disease or ulcerative colitis.

How long infectious colitis lasts differs from person to person. For instance, mild-to-moderate infectious bacterial colitis in children tends to last just one to three days and less than seven days in adults. More severe cases could last for as long as three to four weeks.

Viral colitis should resolve within one to two weeks if you adhere to the treatment prescribed and focus on rehydrating and resting.

There is no broad, uniform amount of time it takes for parasitic colitis to resolve, but Chagas disease generally resolves within eight weeks.

How Can I Avoid Getting Sick?

There are several things you can do to reduce your risk of contracting infectious colitis:

• Always clean utensils thoroughly before and after use.
• Keep raw and cooked foods separate and avoid eating undercooked items.
• Cook meat properly before eating it.
• Avoid swallowing water from swimming pools and bodies of water like lakes.
• When traveling, rely on bottled water, but still make sure you know where the water is coming from and whether it’s clean.
• Wash your hands frequently to avoid the spread of germs.