Crohn’s Disease is an Inflammatory Bowel Disease (IBD) that causes inflammation throughout the digestive tract. There are two stages of Crohn’s Disease: the active flare stage and the remission stage. During an active flare, inflammation is heightened, and symptoms are active. During remission, there are no symptoms present.
Whether you are in an active flare or remission, Crohn’s disease is not contagious and cannot be spread to others. To further understand why Crohn’s is not contagious, let’s look deeper into what causes Crohn’s disease.
What Causes Crohn’s Disease
While the exact cause of Crohn’s is unclear, experts hypothesize there are a few triggers. Current research points to a combination of genetics, environment, and internal intestinal factors as Crohn’s Disease causes. While none of these factors are contagious to those around you, they may trigger your own immune system to mistakenly attack your gastrointestinal system causing inflammation and Crohn’s symptoms.
Research suggests that Crohn’s is largely passed down between generations. Having a family member with Crohn’s does make you more likely to develop Crohn’s at some point in life. As many as 20 percent of individuals who have a first-degree relative with Crohn’s will also develop IBD, and this number continues to rise if you have multiple close family members with IBD.
Experts also believe that your genes may play a role in flare severity and response to medication. Current research has specifically linked four genetic mutations to Crohn’s disease. However, none of these specific genes seem to affect how likely you are to develop Crohn’s or predict the severity of your specific condition.
No matter whether your genetic makeup makes you more or less likely to develop Crohn’s, you cannot pass on Crohn’s or the likelihood of developing Crohn’s to others in the way that you can pass the germs that cause the flu.
Your environment may also play a role in your likelihood of developing Crohn’s. IBD is more commonly seen in individuals who live in developed countries than underdeveloped countries, and more commonly seen in cities than rural areas. Additionally, living in a colder, more northern climate appears to increase the risk for developing Crohn's.
While your environment may play a role in your risk for developing Crohn’s, this cannot be spread between you and others.
Paratuberculosis, a subspecies of Mycobacterium avium, often referred to as MAP, is a pathogen that may be linked to developing Crohn’s disease. One case study evaluated seven individuals from the same high school class that all developed Crohn’s disease. These individuals were not related, which led to the hypothesis that something in their environment triggered the condition. An investigation led to the hypothesis that these individuals may have consumed or swam in water that was contaminated with MAP.
MAP is known to cause a disease that is similar to Crohn’s in farm animals. However, there are many individuals with MAP in their bodies who do not develop Crohn’s disease, so the link is not entirely clear.
More research has shown that multiple factors paired with MAP exposure increase the risk of developing Crohn's including:
- Younger, smaller children need a smaller amount of MAP to develop Crohn’s than older, larger children or adults.
- Female adults are more likely to develop Crohn’s after exposure to MAP. Conversely, male infants are more likely to develop Crohn’s after MAP infection.
- Certain genes appear to impact the way the body processes MAP and affect the likelihood of developing Crohn’s.
- Larger amounts of MAP seem to be more likely to trigger Crohn’s.
- Consuming MAP through contaminated water, milk, or beef appears to make developing Crohn’s more likely.
Even if an individual with Crohn’s is infected with the MAP bacteria, he or she cannot spread the bacteria, or Crohn’s disease, to others. MAP is most often spread in contaminated food or water.
Some individuals specifically worry if physical contact can spread Crohn’s disease between people, but luckily, this is not possible. Shaking hands, hugging, or even sharing food and drinks will not transmit Crohn’s the way these behaviors transmit other illnesses. For example, viruses that cause gastrointestinal symptoms similar to Crohn’s disease symptoms, including diarrhea, can be spread when in close contact with others, while Crohn’s disease itself cannot.
Others may fear that the proximity of reproductive organs and the rectum may allow transmission of Crohn’s, but this is also not supported by any research. Even if you were to come in contact with an individual infected with Crohn’s stool, you will not develop IBD from exposure.
The Bottom Line
Crohn’s disease affects individual’s digestive systems but cannot be spread to other's digestive systems. While many factors including genetics, environments, and MAP exposure affect the likelihood of developing Crohn’s, being in close contact with another person who has Crohn’s does not.
Kaitlyn Willwerth is a Registered Dietitian at OnPoint Nutrition. Kaitlyn's work focuses on providing individualized health and lifestyle coaching and, most importantly, support. She is a Certified LEAP Therapist and has also completed the Monash University 'Low FODMAP Diet for IBS' online training course for health professionals.