Psoriasis is not contagious. You cannot get it from another person. It’s an autoimmune disease that may be more likely if you have certain genes.

Unlike some other skin conditions, psoriasis does not result from bacteria or another type of infection.

Psoriasis is an autoimmune disorder that likely results from a combination of genetic and environmental factors.

More than 7.5 million U.S. adults in the United States have psoriasis.

Keep reading to learn more about how psoriasis does and does not develop.

Psoriasis does not pass from person to person.

According to the American Academy of Dermatology, you must have specific genes to develop the condition.

You may be more likely to have psoriasis if you have a family history of it because you may have inherited some of the genes associated with it. If your parent, grandparent, or sibling has psoriasis, you have a higher risk of developing it.

However, having one or more of these genes doesn’t necessarily mean you will develop the condition.

Researchers don’t fully understand why some people with specific genes develop psoriasis while others do not. But if you do have genes associated with psoriasis, certain environmental triggers may activate the autoimmune condition.

Unlike some other skin conditions, such as scabies, impetigo, and MRSA, psoriasis isn’t caused by infectious bacteria or another type of infection.

Psoriasis is an autoimmune disorder. This means that in people with psoriasis, their immune system targets healthy skin cells with an immune response. The immune response causes inflammation and psoriasis lesions.

Some fungal infections may resemble some types of psoriasis, but they cause different symptoms and have some key differences.

The exact cause of psoriasis isn’t fully understood yet.

It’s thought that overactive T cells are involved. T cells are cells that fight off viruses and bacteria in your body. In people with psoriasis, T cells attack healthy skin cells and activate other immune responses. This increases the production of healthy skin cells, T cells, and other white blood cells.

As a result, too many skin cells accumulate on the outer layer of the skin, which is why some types of psoriasis cause the skin to have a scaly appearance.

New skin cells normally form in weeks, but in people with psoriasis, they form within days. The body doesn’t shed the excess cells, and psoriasis lesions occur.

People with compromised immune systems, including those with HIV or those who get repeated infections, have a higher risk of psoriasis.

Many environmental and lifestyle factors may trigger psoriasis flare-ups. Not everyone with psoriasis has the same triggers. Common triggers include:

Smoking may also be involved in the development of psoriasis and increase the severity of the disease.

Although some people say that allergies and certain foods can trigger psoriasis flares, these claims are mostly anecdotal and do not have scientific evidence.

Does psoriasis spread if you scratch it?

Skin injury, including scratches and cuts, can trigger a psoriasis flare.

Psoriasis can appear in new areas during an active flare. Taking good care of your skin and following a skin routine for psoriasis can help prevent it from spreading to other areas of your body.

Psoriasis is not contagious in any form. It’s an autoimmune condition and not an infectious disease.

You may be more likely to develop psoriasis if a parent, sibling, or grandparent also has psoriasis. This may happen if you have specific inherited genes that increase the risk of psoriasis.

But having these genes does not necessarily mean you will develop psoriasis. The condition likely results from the combination of certain genes and an environmental trigger.