What is Herpetic Whitlow?

Two types of the herpes simplex virus infect humans. HSV-1 infections typically enter the body around the mouth, nose, lips, and other areas of the face. HSV-2 infections usually occur around the genitals and buttocks, but both types can infect any part of the body. The herpes simplex virus can cause primary or recurrent infectious outbreaks, although some people with HSV never experience symptoms. Approximately 20% of people with HSV develop symptomatic infections within 2 to 20 days of initial exposure. Unfortunately, both types of HSV hibernate in nerve cells and remain in the body for life.

Recurrent HSV infections occur when something triggers the dormant virus, which becomes active again and travels to the skin. Herpetic whitlows develop when the fingers or thumbs touch areas that harbor a HSV infection. People can transfer HSV from infected areas on their own bodies or catch it from someone else. Any break in the skin gives HSV an entry point. Torn cuticles are a common route of infection. HSV-1 causes approximately 60% of herpetic whitlow cases, and HSV-2 accounts for the remaining 40%.

People usually develop herpetic whitlows on one finger or thumb, but the infection can occur on multiple digits. A burning or tingling sensation in the affected area is the first symptom. The finger becomes red, swollen, and painful about a week after the first uncomfortable sensations. Small fluid-filled blisters appear in a cluster around a small, bright red patch of skin. Other symptoms include swollen lymph nodes in the elbows or underarm area and a mild fever.

Most people experience herpetic whitlows only once, although recurrent infections are possible and can last seven to ten days from the appearance of the first symptoms until the rash heals. The warning symptoms — burning, itching, or tingling — are still felt, but blisters appear in approximately 24 hours. Recurrent HSV infections are triggered by events such as fever or illness, sun exposure, stress, trauma, surgery, and hormonal changes. The latter frequently occur during menstrual cycles, menopause, or pregnancy.

Most whitlows heal without medical intervention. There is no cure for herpetic whitlows, but oral antiviral medications and topical ointments reduce the severity and duration of outbreaks. Medications also lower the risk of spreading the virus to other people. Suppressive antiviral medications are available for people with frequent recurrent infections. People should start taking medications no more than 48 hours after the first symptoms occur.

Doctors diagnose herpetic whitlow with observations, patient history, and lab tests. A rash or blisters on the thumb or fingers prompt an initial diagnosis. The physician will obtain a swab of the fluid inside the blisters and order a viral culture to confirm the diagnosis. A blood test can also confirm the presence of HSV, but vesicle fluid contains the highest concentration of the virus.

People with active herpetic whitlow infections can spread the virus to other parts of their own bodies and so should cover the affected areas, especially blisters and sores, with a bandage. The bandage should be fairly loose, but tight enough to prevent fluid leakage. Do not pop or drain the blisters, and change the bandage regularly, especially if it becomes damp or soiled. Over-the-counter medications such as NSAIDs and ice packs relieve discomfort and inflammation. People with contact lenses may want to wear glasses until the blisters have healed to avoid transferring the virus to their eyes.

Fluid inside blisters during a herpetic whitlow is extremely contagious. Other people in the home need to take precautions. Do not share towels, brushes, soaps, or other hygiene tools and products. Wash hands frequently with soap and water. Alcohol-based hand sanitizers must stay on the skin for at least 15 seconds to kill pathogens. Keep hands moisturized to avoid cracks and chafing that are entry points for the virus. Health care workers should always wear gloves with every patient, even if the patient has no visible signs of infection.

Approximately 35% of people with herpetic whitlows develop a secondary infection. We use our hands and fingers for hundreds of mindless tasks every day. Any fluid-filled blisters that rupture and become sores are prime sites for bacterial infection. Symptoms of a secondary infection include white or green discharge, increased pain and inflammation, and, in advanced infection, a foul odor.

Whitlows typically heal with no long-term effects, but the virus can cause permanent nerve damage in rare cases. People with compromised immune systems have the greatest risk of this complication. Symptoms of nerve damage include numbness, burning, or tingling in the affected area. These symptoms are normal during a herpetic whitlow outbreak and may last longer than the rash. Medical professionals usually do not consider nerve damage unless symptoms persist for at least six months after the rash has healed.