There are over a 150 different types of human papilloma virus, the virus that causes verruca vulgaris, more commonly referred to as warts. Warts are very common…in Australia 22% and in the Netherlands 33% of children were found to have cutaneous warts.
Human papillomavirus type 1, 2, 4, 27, 57, and 63 cause common warts. They occur mostly between the ages of 5-20. In one series only 15% were documented after the age of 35. They are spread by direct contact with infected individuals. The natural history is spontaneous resolution and in children clearance rates are as follows (from Andrews’ Diseases of the Skin):
- 23% clear by 2 months
- 30% clear by 3 months
- 50% clear by 1 year
- 65-78% clear by 2 years
- 90% clear by 5 years
The frustrating part is that recurrent warts are common and many patients that have problems with specific types of warts, such as common warts, acquire them again. It has also been reported that the papillomavirus can remain dormant for up to 4 years before expressing clinical lesions. Risk factors include frequent hand washing or hand immersion in water, family members with warts, public exposure (such as swimming pools, public showers) and going barefoot. The prevalence in meat handlers approaches 50% and these are referred to as “butcher warts.” It is very common in meat handlers, fish handlers and other abattoir workers. Any individuals with immunodeficiencies, such as HIV disease, are susceptible and often develop many warts.
Subungual warts may progress to nail destruction. Also, subungual warts may transform into a squamous cell carcinoma and I will talk about this more in a separate blog. Patients can seed the wart along the skin if they scratch through a wart…this is called Koebnerization. I will talk about other types, plantar warts, flat warts, filiform warts and genital warts in future blogs.
TREATMENT: The treatments for warts are numerous and produce a wide range of results. There is no “Gold Standard” for treating warts. Nothing has been proven to be the best treatment. I, therefore, do not perform procedures that leave scars, knowing that most of these lesions will resolve spontaneously at some point in time. Over the counter treatments do work, but I do not recommend the “cold spray” that is commercially available. It does not reach a cold enough temperature in quick enough period of time to be effective and in the wrong hands can produce scarring. In my clinic we utilize liquid nitrogen and in children use a blistering agent (Canthacur) that induces a painless blister. I will discuss various treatment options and tricks you can do at home to help treat these very difficult and frustrating growths if you come into my clinic… To read more about warts click HERE and for a comprehensive review of treatment options click HERE.