Diarrhea is usually contagious when it is acute, meaning it comes on suddenly.
Acute diarrhea is often sparked by a microorganism such as a bacteria or virus.
These microorganisms can be easily passed between people or even between animals and people.
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Chronic or long-lasting cases of diarrhea are more likely to have causes that are not contagious.
Diarrhea is defined as loose or watery stool that occurs three or more times per day.
How Does Diarrhea Spread?
The most common causes of diarrhea are viral, bacterial, and parasitic infections.
Infectious diarrheal diseases are contagious, meaning that they can be spread between people.
Things that people touch a lot like doorknobs, buttons, and counters can be easily contaminated.
People can also catch infections that cause diarrhea if a sick person makes food for them.
Kids can get infectious diarrhea easily because they tend to put their hands and objects in their mouths.
Animals can also contaminate sources of water and surfaces with pathogens that spread infectious diarrhea.
These illnesses can be transmitted easily when people don’t wash their hands after touching an animal.
Most infectious diarrheal diseases go away on their own or can be treated.
However, some types of infectious diarrhea are harder to treat.
People may have diarrhea that lasts a long time and leads to complications.
How Long Are You Contagious With Diarrhea?
You might still be able to spread the infection for a few more days after you start feeling well.
Viral Causes
Viruses are the most common cause of diarrhea.
Dysenteric disease is an infection that causes diarrhea containing blood or mucus.
These single-celled organisms come in many forms.
What Is Non-Infectious Diarrhea?
Diarrhea can also be non-infectious.
Diarrhea due to these conditions cannot be spread to other people.
However, diarrhea is the second leading cause of death in children in the developing world.
It’s also a major contributor to work absenteeism and loss of productivity in the United States' workforce.
The elderly, very young children, and people with compromised immune systems are especially vulnerable to diarrheal infections.
These groups are also more likely to die from complications.
How Is Contagious Diarrhea Diagnosed?
This requires seeing a healthcare provider.
They can also run a series of tests to identify the cause of diarrhea.
Finding out whether diarrhea is infectious or not has several steps:
How Is Infectious Diarrhea Treated?
The treatment for diarrhea depends on the cause and how sick a person is.
Medications can treat infectious diarrheal diseases.
The fluid can also be delivered intravenously (through a vein) if the dehydration is especially severe.
You may have a fever with infectious diarrhea and feel sick.
An over-the-counter (OTC) fever-reducing or pain-relieving medication may help.
How Is Contagious Diarrhea Prevented?
Viral, bacterial, and parasitic causes of diarrhea can be easily spread from person to person.
Children, the elderly, and immunocompromised people are more likely to contract and spread these diarrheal illnesses.
They are also more at risk for complications and death.
Your healthcare provider can treat severe diarrhea with medications and fluids.
Some infectious illnesses that cause diarrhea do not always cause a fever.
Acute diarrhea usually lasts a few days at most.
Chronic diarrhea lasts for four weeks or longer.
It can also come and go.
Your provider can test your stool and see if it has germslike bacteria or parasitesin it.
There are also blood tests that can help your provider see if you have a virus.
Antibiotics are only used when diarrhea is due to bacteria.
Three examples of antibiotics that are used for acute diarrhea include ciprofloxacin, cephalosporin, and azithromycin.
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