What Common Skin Infections Look Like

Recognizing rashes and lesions caused by bacteria, viruses, or fungi

Although one important function of skin is to help protect the body from harmful microbes, sometimes it can become the target of infection-causing bacteria, viruses, or fungi. When this happens, there will invariably be a change in the appearance of the skin, such as a lesion or a rash.

Often it's possible to recognize a particular skin infection based on what it looks like and where it's located, and so it can be helpful to be familiar with the visible symptoms of common ones.



This photo contains content that some people may find graphic or disturbing.


Alex Tihonov / Getty Images

Chickenpox is a skin infection caused by the varicella-zoster virus. Early in a chickenpox infection, the rash is characterized by clusters of vesicles (small sacs filled with fluid) on an erythematous (reddened skin) base.

These distinctive lesions, which have been described as "dewdrops on a rose petal," are preceded by flu-like symptoms. They usually crop up first on the face, scalp, and torso, and then spread to the arms and legs. Within a few days of appearing, the clusters of vesicles grow together to make larger lesions that crust and scab.

Chickenpox is highly contagious. It spreads easily through skin-to-skin contact as well as by breathing in infected droplets sent into the air when someone sick with the virus coughs or sneezes.

Once considered a common childhood illness, the incidence of chickenpox has declined dramatically since the varicella vaccine was introduced in 1995.


Fungal Nail Infection

This photo contains content that some people may find graphic or disturbing.

nail fungus in whit

Cunaplus_M.Faba / Getty Images

Thickened, discolored toenails and fingernails are often due to a fungal infection of the nail bed (the skin beneath the nail), matrix (where the growth of the nail begins), or nail plate (the nail itself) caused by a fungus called Trichophyton rubrum. The medical terms for such infections are onychomycosis or tinea unguium.

Although fungal nail infections are not technically skin infections, they tend to affect the skin surrounding the affected nail. Symptoms include:

  • Separation of the nail plate from the nail bed
  • Discoloration (yellowing or whitening) of the end of the nail
  • Formation of debris underneath the nail
  • Growth of fungi into the nail, causing it to become fragile and crumbly

Topical medications are not effective in treating nail infections. It usually takes an oral anti-fungal medication to clear one up.


Cold Sore

cold sore
Todd Keith / Getty Images

Also known as fever blisters, cold sores are lesions that appear anywhere on or around the lips, mouth, or nostrils. They begin as small fluid-filled sacs called vesicles. The vesicles form ulcers that eventually become crusted over before healing and disappearing. Cold sores do not leave scars.

The majority of cold sores are caused by type 1 herpes simplex virus (HSV-1) and are clinically known as oral herpes (herpes labialis). However, some may be caused by type 2 HSV (HSV-2), the same virus that causes genital herpes. It can be transmitted to the mouth by oral sex with someone who has an active genital herpes infection.


Rocky Mountain Spotted Fever

This photo contains content that some people may find graphic or disturbing.

Rocky Mountain spotted fever
Smith Collection/Gado / Getty Images

Rocky Mountain spotted fever (RMSF) is a potentially fatal disease characterized by a rash made up of small, red, flat spots that most often appear first on the ankles and wrists. As the rash progresses, the spots move to the palms, soles of the feet, and trunk and become bumpier.

Around 10% of people infected never develop a rash. For those who do, the spots usually show up around four days into the infection, which is caused by a bacterium called Rickettsia rickettsii.

Rocky Mountain spotted fever is spread via the bite of a tick infected with the bacterium. Although it has appeared throughout the United States, according to the Centers for Disease Control and Prevention, 60% of cases occur in North Carolina, Oklahoma, Arkansas, Tennessee, and Missouri.



Impetigo rash beneath a mans lower lip

Impetigo is a bacterial infection of the upper layers of the skin. The most common type, herpetic impetigo, begins as an outbreak of tiny blisters that rupture, ooze fluid, and eventually form a honey-colored crust. It can be somewhat itchy but rarely causes pain or discomfort.

Impetigo is caused when either Streptococcus bacteria or Staphylococcus bacteria enters the body through a break in the skin such as a cut, scrape, burn, or insect bite. Children often develop impetigo after a cold when the skin of their noses is raw. Besides the face, impetigo most often appears on the arms or legs.

A less common type, called bullous impetigo, leads to the formation of large blisters known as bullae. This form of impetigo is more commonly seen in newborns. Diagnosing impetigo sometimes requires a bacterial culture. Antibiotics are the typical treatment.



This photo contains content that some people may find graphic or disturbing.

Tinea corporis infection (ringworm)

OGphoto / Getty Images

Ringworm, or tinea corporis, is not a worm, but rather a fungal infection. It starts out as a flat scaly lesion that extends outward in all directions to form a circular shape. Ringworm is so named because the perimeter of the circle is raised and scaly, forming a ring around the central area. Sometimes vesicles develop.

Ringworm rashes tend to be itchy and can cause permanent hair loss if they affect the scalp or other hair-bearing areas and are not treated. Thanks to its distinctive appearance, ringworm is easily diagnosed and can be effectively treated with oral or topical medications.


Ingrown Toenail

This photo contains content that some people may find graphic or disturbing.

ingrown nail.

apomares / Getty Images

An ingrown toenail develops when, usually due to prolonged pressure of the nail against the skin of the toe, the nail grows partially into the skin, piercing it and causing irritation, pain, and swelling.

While not an infection in and of itself, an ingrown toenail can become infected when bacteria are able to enter the broken skin. In that case, the skin around the nail will become red and swollen; there may also be drainage of pus and an odor.

Treatment may include soaking the nail in water to which Epsom salts have been added, wearing sandals or shoes with a wide toe box until the toe is healed, and an oral antibiotic to clear up the infection.


Athlete's Foot

This photo contains content that some people may find graphic or disturbing.

Athlete's foot

ProjectManhattan / Wikimedia Commons / CC BY 3.0 

Athlete's foot, or tinea pedis, is a common fungal infection that (obviously) affects the feet. There are three types, each of which has a distinctive appearance:

  • Chronic interdigital athlete’s foot: The most common form of athlete's foot, it's characterized by skin dryness and flaking, maceration, and fissures that most often develop between the fourth and fifth toes.
  • Chronic scaly athlete’s foot (moccasin type): Caused by a fungus called Trichophyton rubrum, this type of athlete's foot is characterized by fine, silvery scaling with pink tender skin underneath.
  • Acute vesicular athlete’s foot: Also known as jungle rot, this infection caused by Trichophyton mentagrophytes is characterized by painful blisters on the sole or top of the foot. It sometimes develops in people who have chronic interdigital toe web infection.

Wearing damp socks or tight shoes, or going barefoot in communal areas such as gym showers and public pools, can increase the risk of athlete's foot. Men and children who haven't reached puberty are substantially more likely than women to develop this infection.

Depending on the severity, athlete's foot is treated with an over-the-counter antifungal cream or spray or a prescription-strength version.

A Word From Verywell

There are many types of skin infections but the one thing all have in common is they can be unsightly, uncomfortable, and even painful. Most are easy to identify and treat; rarely is a skin infection a serious threat to overall health.

It's important to have any lesion, rash, or change in the appearance of skin checked by a doctor without delay, however, as these sometimes can be symptoms of skin cancer.

Was this page helpful?
Article Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Pang SM, Pang JYY, Fook-Chong S, Tan AL. Tinea unguium onychomycosis caused by dermatophytes: a ten-year (2005-2014) retrospective study in a tertiary hospital in SingaporeSingapore Med J. 2018;59(10):524–527. doi:10.11622/smedj.2018037

  2. Ely JW, Rosenfeld S, Seabury stone M. Diagnosis and management of tinea infections. Am Fam Physician. 2014;90(10):702-10.