What Causes Warts? HPV and How They Form

Warts are caused by the human papillomavirus (HPV), a common virus with over 100 different types. While anyone can develop warts, not everyone who comes in contact with HPV will get them. Your immune system plays a key role in whether you develop warts after exposure to the virus.

Understanding what causes warts can help you take steps to prevent them and know when to seek treatment.

The HPV Virus Behind Warts

Different HPV types cause different kinds of warts. Common warts on your hands and feet are typically caused by HPV types 2 and 4, while plantar warts on the bottom of your feet often come from HPV types 1, 2, and 4. These are completely different from the HPV types that affect other areas of the body.

The virus works by infecting the top layer of your skin and causing extra cells to grow quickly, creating the rough, raised bump you see as a wart.

How HPV Enters Your Skin

HPV cannot infect healthy, intact skin. The virus enters your body through small cuts, scrapes, or damaged areas on your skin. Even tiny breaks you cannot see can provide an entry point for the virus.

You can pick up HPV through:

• Direct contact with someone else's wart
• Touching surfaces that have the virus, such as gym floors or pool areas
• Using shared towels, razors, or other personal items
• Walking barefoot in public showers or locker rooms

Moist and soft skin is more vulnerable to HPV infection, which is why warts commonly appear after swimming or in areas that stay damp.

Why Some People Get Warts and Others Don't

Many people come in contact with HPV but never develop warts. Your immune system determines whether the virus takes hold. When your immune system is strong, it usually fights off the virus before warts can form. In fact, most HPV infections clear on their own within two years.

Several factors affect your individual susceptibility:

• Genetics may make some people more prone to developing warts
• Age plays a role, with children and teenagers more susceptible than adults
• Skin conditions or frequent skin injuries increase your risk
• Weakened immune systems make you more vulnerable to warts

Risk Factors for Getting Warts

Certain situations increase your chances of developing warts. People with weakened immune systems, including those with HIV/AIDS or taking medications after organ transplants, face higher risk. Children develop warts more often than adults because their immune systems are still developing.

Frequent exposure in communal settings like gyms, pools, and schools also raises your likelihood of infection. If you already have a wart, you can spread the virus to other parts of your body by touching or picking at it.

When to See a Dermatologist

Consult a dermatologist if warts are painful, bleeding, or spreading rapidly, if you have multiple warts that don't respond to over-the-counter treatments, or if you're unsure whether a growth is actually a wart. People with weakened immune systems or diabetes should see a doctor before treating warts on their own.

While warts are harmless for most people, understanding their viral cause helps you take preventive steps and make informed decisions about treatment.