Strep and OCD: Surprising Connections

When your child has strep throat (an infection caused by the Streptococcus bacteria), you probably assume that the symptoms will be limited to the throat area. However, there's been much debate in recent years about whether this illness can also lead patients to experience a range of obsessive-compulsive behaviors.

Strep and OCD

If you think it sounds strange that strep throat could be related to obsessive actions, you're not alone. Many public health advocates have found the concept of a link between strep and obsessive compulsive disorder, commonly known as OCD, to be quite difficult to swallow.

The Strep and OCD Link

Yet as unlikely as the combination might seem, more than two decades ago, researchers from the National Institute of Mental Health noticed children who'd recently recovered from strep throat were exhibiting some sudden obsessive behaviors, including washing their hands frequently.

Although the strep symptoms were gone when the behavior occurred, when the children involved underwent testing, it was discovered that they still had antibodies left from the infection. Further, a repeated course of antibiotics seemed to improve the situation.

Delving Deeper into Strep and OCD

One hypothesis to explain this situation is that exposure to the strep bacteria may cause the immune system to overreact. The thought is that the antibodies attempt to attack the infection, but instead end up affecting the brain enzyme and interfering with neuron activity there.

Another study, this one included in the Journal of Neuroimmunology in July of 2006, also found that children with movement disorders also tested with high amounts of strep antibodies, further making the link between the two behaviors.

Animal Studies on Strep and OCD

To better understand what this means, scientists from Columbia University's Center for Infection and Immunity tried infecting mice with the strep bacteria so they could see if this theory plays out. The animals affected exhibited neurological and psychiatric symptoms and their brains showed antibody deposits consistent with those seen on humans.

These findings reinforce the idea that strep may cause a condition scientists are calling PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections). This may be to blame for at least a quarter of all obsessive-compulsive conditions diagnosed today, including Tourette Syndrome and other tic-based behaviors. Scientists are continuing to explore the connection to learn more about how to treat strep effectively and head off this situation.

What You Can Do

If your child suddenly has any OCD symptoms and has had strep throat recently, you should share this information with your pediatrician and see if he thinks the two factors are related. If so, you can ask whether taking another course of treatment may help to resolve some of the existing issues. Further, you should understand that children with multiple strep infections could be at even higher risk for the strep and OCD relationship.

If your child has OCD, until the strep connection is more fully understood, your pediatrician may also want to use behavioral therapy, sometimes in conjunction with nutritional supplements, to treat the symptoms. This type of approach may be the most effective, but every child will respond differently so it's important to let your doctor determine what's best for your specific situation.


Columbia University Mailman School of Public Health

National Institute of Mental Health (NIMH)

Scientific American