Herpetic whitlow is a common type of skin infection that affects the fingers. It is caused by a virus and is mostly transmitted through physical contact.
The herpes simplex virus (HSV) causes red, painful blisters to appear on the skin of the fingertips. In rare cases, it can affect the toes too. The virus is also referred to differently depending on how it is contracted: primary HSV (HSV-1) when you contract it for the first time, and recurrent or secondary HSV (HSV-2) when it occurs again.
HSV-1 is responsible for approximately 60% of herpetic whitlow cases, while HSV-2 causes the other 40%.
In herpetic whitlow, the herpes simplex virus (HSV) invades the skin cells, clones or multiplies itself and becomes permanently integrated into your body (i.e., once you contract the virus, it lies dormant in your body). The symptoms of herpetic whitlow will manifest once the virus is triggered to activate or reactivate.1
Both types of HSV produce two kinds of infection: primary and recurrent infection. They usually occur in the same location, though the recurrent kind is often less severe than the primary infection. They are also often self-limiting - i.e., they will mostly go away on their own and usually resolve within 2 to 4 weeks.2
Symptoms will begin to appear between 2 to 20 days after exposure, and infection can spread to both ends of the fingers, sometimes involving the nail bed. Although it’s common to have herpetic lesions on one finger only, it can occasionally occur on two or more fingers.
Causes of herpetic whitlow
HSV is the cause of herpetic whitlow and is transmitted through physical contact with an infected person.
When a cut on your skin (usually a torn cuticle) or open sore is exposed to infected body fluids of someone infected by the HSV, the virus penetrates the cells of the dermis and infects your body, too.3
Infections caused by HSV-1 are more commonly seen on the fingers of healthcare professionals due to their exposure to the oral secretions of infected patients. It is also common in children as a result of their disposition to finger or thumb-sucking.
Patients with HSV-2 are seen more in the general population, and most HSV-2 cases of herpetic whitlow are due to a previous genital herpes infection.
Some modes of transmission include:
- Touching genital sores or cold sores with bare fingers and touching skin or other surfaces afterwards
- Biting dirty nails or sucking unwashed fingers
- Autoinoculation (a process where the virus spreads from other herpetic sores to your fingers)
Signs and symptoms of herpetic whitlow
Following exposure to herpes simplex virus, the patient will experience the following symptoms:
- Tiny, rash-looking blisters called vesicles that form around the nail bed
- Large, fluid-filled blisters called bullae on the finger (a collection of vesicles) eventually rupture to form sores and crusts
- Painful swelling of the affected finger
- Colour change of the skin surrounding the nail and affected area
- Red streaks radiating from the finger
- Swollen lymph nodes under the arm or elbow
- Fever (usually a few days before any sores or pain appear)
In most cases, pain and a tingling sensation are felt, and then the skin changes colour to red or a shade darker than your usual skin tone. The symptoms usually occur in one finger but can also be seen in more than one in rare cases.
Management and treatment for herpetic whitlow
Since herpetic whitlow is a self-limiting infection (it goes away on its own), the treatment plan focuses on relieving the symptoms and preventing secondary infection.
The symptoms usually stop and go away in 2-4 weeks. However, some studies have shown that by taking antiviral medications (oral or topical) within 48 hours of symptoms appearing, the infection duration will be as much as 4 days and can stop the active virus from infecting another piece of your own skin, another person or a nearby surface.4,5
Antibiotics may be introduced when there is a suspected case of a bacterial infection, otherwise known as bacterial superinfection, and over-the-counter pain reliefs (such as Paracetamol and Ibuprofen) can be administered to relieve blister pain.
You should avoid making a cut (incision) to drain the fluid in the blisters, as this can lead to the movement of the herpes virus into the bloodstream and/or a bacterial superinfection.
Other blister management techniques include:
- Covering them with bandages to help prevent the virus from spreading to others or another area of your own skin
- Applying a compress to reduce swelling and pain
- Wearing glasses instead of contact lenses (if applicable) to avoid contact with the eyes until sores heal
- Avoid popping the blisters so that the virus doesn’t spread
Diagnosis of herpetic whitlow is based on the study of symptoms appearing on the infected finger. Some doctors may also carry out a blood test or a swab of the infected skin to be sent to a lab for testing.
If you are diagnosed with a primary infection, the most likely cause of your herpetic whitlow sore will be a recent herpes infection caused by direct contact of the finger with the infected skin. However, if you are diagnosed with a recurrent infection, the most likely cause will be a previous herpetic whitlow infection in the same area.6
A Tzanck test can also be performed to confirm the diagnosis of the infection.
How can I prevent herpetic whitlow
Herpes simplex virus infections are contagious; hence it can prove difficult to prevent when you come in contact with someone that has it. The following measures can help to reduce your chances of getting the infection:
- Ensure to wash your hands regularly with soap and water
- Keep a hand sanitiser handy so you can use it when soap and water are not available
- Ensure your child doesn't suck their fingers
- Healthcare workers should wear gloves, especially when in contact with people’s mouths
- Avoid sharing personal items such as towels or toothbrushes
How common is herpetic whitlow
Although herpetic whitlow is common among people with the herpes simplex virus, the infection is rare in the general population.
Who is at risk of herpetic whitlow?
This infection can affect anyone at any stage of their life. People who have been found to be highly predisposed to developing it include:
- Children that suck their fingers
- People with a weakened immune system
- People exposed to genital herpes
- People exposed to other people’s mouths (such as doctors, nurses and dentists)
- Some athletes who have physical contact with their opponents, like wrestlers
If you have already been diagnosed with a previous case of HSV, you may be at risk of developing herpetic whitlow if you have or experience:
- A weakened immune system
- Severe stress
- Trauma (physical, mental or emotional)
- Hormonal imbalance
- Allergies such as hayfever
Is herpetic whitlow contagious
Herpetic whitlow is very contagious. All it takes to become infected is to have a cut on your skin and come into direct contact with a carrier of the virus.
When should I see a doctor?
You should see a doctor as soon as you notice a sore or tender swelling on your finger. The earlier the symptoms are detected and managed, the less the infection will spread. Urgent care from the healthcare provider is required when the whitlow infection is accompanied by fever or a general feeling of illness.
Herpetic whitlow is a contagious and painful infection of the skin. While it usually can go away on its own after 2 to 4 weeks, the use of treatments such as antiviral drugs and topical solutions can help shorten the duration of symptoms. It is also important to avoid touching the infected finger or the other parts of the body with the sore as the causative HSV is very contagious and could easily reinfect you or spread to others. It is advisable to visit your doctor as soon as you notice the signs and symptoms of herpetic whitlow because, as with any viral infection, you can become somewhat unwell if left untreated.
- Herpetic whitlow [Internet] [cited 23rd June 2023] Available from https://www.ncbi.nlm.nih.gov/books/NBK482379/
- Adışen E, Önder M. Acral manifestations of viral infections. Clinics in Dermatology. 2017 Jan 1;35(1):40-9.
- Betz D, Fane K. Herpetic whitlow. InStatPearls [Internet] 2022 Aug 1. StatPearls Publishing.
- Rerucha CM, Ewing JT, Oppenlander KE, Cowan WC. Acute hand infections. American Family Physician. 2019 Feb 15;99(4):228-36.
- Herpetic Whitlow treatment and management [Internet] [Cited on 23rd June 2023] Available from https://emedicine.medscape.com/article/788056-treatment
- Herpetic Whitlow [Internet] [Cited on 23rd June 2023] Available from https://cdn.mdedge.com/files/s3fs-public/Document/September-2017/079030193.pdf