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What is OCDOCD SubtypesWhat Is Contamination OCD?

What Is Contamination OCD?

9 min read
Nicholas Farrell, Ph.D

By Nicholas Farrell, Ph.D

Apr 16, 2021

Contamination OCD is a subtype of obsessive-compulsive disorder (OCD) where a person experiences obsessive thoughts around fears of becoming contaminated, contaminating others, or contracting and spreading a disease. These obsessive thoughts drive people to engage in various compulsions aimed at alleviating their anxieties about contamination (e.g., showering for hours or until they feel clean). 

Contamination OCD is one of the more common subtypes of OCD, and there are many different symptoms any individual person can experience. They could either fear contracting a specific disease or illness (e.g., botulism) or fear contamination in general. Some physical compulsions include excessive hand-washing or showering, avoiding crowded spaces, using hand sanitizer excessively, or frequently changing one’s clothes. 

Excessive research is another compulsion, and a person may spend hours online looking up disease, bacteria, and how to prevent contamination. For example, they may spend an entire night researching the potential of getting food poisoning and become convinced their last meal will make them sick, despite no physical symptoms. Sufferers may avoid situations or people. They might leave garbage in their home due to fear of becoming contaminated while disposing of it, or spend hours making a mental list of what is clean and what is dirty. (e.g., I let my friend use my pen, and I touched the pen when she gave it back to me, and now everything I touched is dirty).

People with contamination OCD may also experience fears of emotional contamination. For example, a person may fear that thinking or speaking about an illness will contaminate them. They may avoid talking about someone they know is sick because they are afraid any mention of this person will contaminate others. They might fear watching a movie or reading a book about someone ill will make them sick. 

People with contamination OCD are driven to know whether something is contaminated with 100% certainty. As long as even a tiny fraction of doubt remains, the obsessions and compulsions will continue. Even when it seems a compulsion has effectively relieved their anxiety (e.g., I just washed my hands 10 times, so now I finally know I’m clean), it’s only a matter of time before more obsessive thoughts arise.

Contamination OCD can be incredibly time-consuming, drain someone of energy, and incapacitate them from being able to function in their everyday life. These obsessive thoughts and compulsive behaviors can feel impossible to stop.

They will go on and on, often for hours or days, and won’t leave until the person has found reassurance, either internally or externally, to dismiss these concerns.

Examples of contamination OCD obsessions

  • I want to go to that coffee shop but I am worried their coffee is contaminated by using “dirty” water.
  • What if germs are on the doorknob and I touch it and get sick?
  • What if my hands are unclean? I just washed them but they still feel unclean.
  • I’m worried I’m going to get contaminated from trying on clothes in this store.
  • What if this food is rotten and I get sick?
  • I need to shower after being outside.
  • There’s no way I can take the bus. There are too many people on it and I will definitely catch something.
  • I think there are germs on my skin. Something just doesn’t feel right.
  • I don’t know why, but I just have this feeling I’m going to get sick. 
  • How many people used this pen before me? 
  • Could I catch something by walking by someone who is sick? 
  • Is the air being properly ventilated in this space? I can feel sick already. I don’t want to be here.
  • What if I have an STI?
  • Are those coffee lids in that coffee shop clean? What if one of the baristas laughed and their spit landed on the coffee top, and now I have an STI? That’s probably unlikely. But maybe I should get tested just in case. 
  • I think my friend transferred her negative emotions to me yesterday when we met. She was in a very bad mood yesterday when we spoke, and today I am feeling down. I know it was because of her. Now my whole week will be ruined.
  • I read an article about someone with cancer, and I’m worried I’m going to get cancer now.
  • What if I’m sick and asymptomatic and I give people an illness? How can I be sure I’m not sick? 
  • I can’t believe I agreed to bring food to the potluck. What if I contaminate everyone with my germs? 

Examples of contamination OCD compulsions 

  • Repetitive actions: People with contamination OCD may engage in repetitive behaviors meant to alleviate the anxiety of potential contamination. Some examples include:
    • Repeatedly and excessively washing one’s hands or showering
    • Using harsh chemicals to stay clean
    • Excessively and repeatedly sterilizing objects in a space
    • Throwing away clothes that might be contaminated
    • Scraping off skin one thinks might be contaminated 
    • Excessively changing one’s clothes
  • Avoidance: People with contamination OCD may avoid certain situations or people who they feel are contaminated. A person might avoid touching specific objects, taking public transportation, or attending certain social gatherings and events for fear of becoming ill. Someone may also avoid specific people they feel are contaminated with something, even if they do not know exactly what they are contaminated with. They may also avoid mentioning a specific name of an illness in order not to get sick, or prevent themselves from thinking or speaking about someone ill. They may create a safe space or “off-limits” section in their home that is clean and that others cannot enter.
  • Reassurance seeking: People with contamination OCD often seek continual reassurance from the people in their lives to make sure something is not contaminated. They may repeatedly ask questions about the same topic. For example, they might ask, “Hey, are these apples fresh? Do you happen to remember when you got them? Are you sure? And you didn’t notice anything strange at the supermarket, right?” A person may also seek reassurance from strangers in online forums. They may post questions about specific scenarios and ask whether there’s a chance they could get sick or contaminate someone else.
  • Mental review: People with contamination OCD may make mental lists about what is clean and what is dirty. For example, if a plumber comes to their home for repair, they may mentally track everything the plumber touches, and then spend hours desanitizing each item just in case this person was contaminated.
  • Performing rituals: A person may perform certain rituals like praying, knocking, repeating or thinking certain thoughts. They may decide that they must repeat to themselves, “I am clean,” seven times every time they enter their home.
  • Excessive research: A person may spend hours online researching the potential of contracting a certain disease or illness. They may Google, “How long does it take to know if you are sick?” or, “How are STIs transmitted?” or, “Are STI tests always accurate?” 

Contamination OCD ERP therapy

The best course of treatment for contamination OCD, like all types of OCD, is exposure and response prevention (ERP) therapy. The idea behind ERP is that repeated exposure to obsessive thoughts, without engaging in compulsions, is the most effective way to treat OCD. When you continually reach out for the compulsions, it only strengthens your need to engage them. On the other hand, when you prevent yourself from engaging in your compulsions, you teach yourself a new way to respond and will very likely experience a noticeable reduction in your anxiety. 

ERP is considered the gold standard for OCD treatment and has been found to be effective for 80% of OCD patients. The majority of patients experience results within 12-20 sessions. As part of ERP therapy, you will track your obsessions and compulsions and make a list of how distressing each thought is. You’ll work with your therapist to slowly put yourself into situations that bring on your obsessions. This has to be carefully planned to ensure it’s effective, and so that you’re gradually building toward your goal rather than moving too quickly and getting completely overwhelmed.

Examples of contamination OCD ERP exposure 

Let’s say you struggle with contamination OCD and feel that you cannot allow anyone to enter your living room for fear that a guest will contaminate the space. This compulsion has become painfully isolating, and it prevents you from hosting friends and feeling close to the people in your life. You may truly want to host a friend, but the fear of contamination prevents you from being able to.

With a therapist, you’ll work toward overcoming the compulsion to keep your living room off-limits so that you’re able to host people in your space again. At first, you might think, “I can’t have anyone over. That’s impossible. I’ll do anything but that.” If an exposure feels too overwhelming to start with, you’ll work with the therapist to find the right intensity for you. Perhaps inviting a friend is too scary to start, but bringing an object you deem to be contaminated into your living room is still more manageable. 

Once you choose a plan, you’ll work with your therapist on the emotions that come up during the exposures. They may bring up many of the fears you’ve been trying to alleviate with your compulsions (e.g., What if I bring an object into my space and my whole living room becomes contaminated?). However, when you realize your worst fears aren’t actualized through these actions, you’ll start to become more comfortable with the uncertainty and anxiety driving your compulsive behaviors. With practice, you’ll find the intense need to engage in your compulsion will wane and you reach a point where you can invite friends over without fear. 

How to get help 

Contamination OCD may be tricky to diagnose because oftentimes the symptoms are not visible to an outside observer. For example, a person may engage in mental compulsions around contamination (like repeating statements to themselves) as opposed to physical compulsions. However, a mental health professional who specializes in OCD will be able to make an accurate diagnosis. If you’re interested in learning about contamination OCD and how it’s treated with ERP, you can schedule a free call with the NOCD clinical team to find out how this type of treatment can help you. All of our therapists specialize in OCD and receive ERP-specific training and ongoing guidance from our clinical leadership team. Many of them have dealt with OCD themselves and understand how crucial ERP therapy is. NOCD offers live face-to-face video therapy sessions with OCD therapists, in addition to ongoing support on the NOCD telehealth app, so that you’re fully supported during the course of your treatment. You can also join our Contamination OCD community and get 24/7 access to personalized self-management tools built by people who have been through OCD and successfully recovered.

Learn more about contamination OCD

Learn more about ERP
Nicholas Farrell, Ph.D

Nicholas R. Farrell, Ph.D. is a psychologist and the Regional Clinical Director at NOCD where he provides clinical leadership and direction for our teletherapy services. In this role, he works closely with our clinical leadership team to provide a high-quality training and developmental experience for all of our therapists with the aim of maximizing treatment effectiveness and improving our members’ experience. Dr. Farrell received his master's and doctoral degrees in Clinical Psychology from the University of Wyoming (Laramie, WY, USA). He served as a graduate research assistant in the Anxiety Disorders Research Laboratory at the University of Wyoming from 2010 to 2015 and completed his predoctoral internship training as a psychology resident at St. Joseph’s Healthcare Hamilton (Ontario, Canada).