Various pathogens can cause skin infections, such as bacteria, viruses, fungi, and parasites. The symptoms, treatment, and outlook will depend on the cause.

Infections can vary from mild to serious. Most skin infections are highly treatable. However, an infection can become more serious if it goes deeper into the skin or spreads across much of the body.

People with a weakened immune system have a higher risk of skin infections and complications from skin infections. This could be due to:

a health condition, such as HIV, diabetes, poor circulation, or malnutrition
a side effect of medication, such as chemotherapy or biologic drug use
being older or very young
have skin folds due to obesity
Over-the-counter medications and home remedies can often treat mild infections, but other infections may need medical attention.

Read on to learn more about skin infections and what to do if you have one.

What are the types of skin infections?
The following are four different types of skin infections:

1. Bacterial skin infections
Bacterial skin infections occur when bacteria enter the skin, either from an outside source or because they are present on the skin. They can enter the skin through a hair follicle or after a wound.

Anthrax is one type of bacterium that can enter from the environment. Staphylococcus and Streptococcus are bacteria that are commonly present on the skin and only cause a problem in certain circumstances. Lyme disease is a tick-borne infection that causes skin symptoms.

Bacterial infections can be systemic or local. Systemic infections can cause symptoms throughout the whole body, such as a fever, while local infections only affect a specific area. Some bacterial infections can begin in one area and spread throughout the body.

Some bacterial skin infections, such as impetigo, can spread between people through direct skin contact or with bodily fluids, contaminated food or water, or by touching surfaces where bacteria are present. Others, such as cellulitis, are not contagious.