What are warts?
Warts are small growths on the skin that are caused by the human papilloma virus (HPV). They generally appear as skin-colored bumps with a raised, rough surface. Although much of the time warts are harmless, and clear spontaneously within 1-2 years,[1] they may also require medical treatment depending on their location and symptoms.[2][3] Generally, warts are uncommon in infants, common in children, and decline in prevalence into adulthood.[4] It is important to note that warts are caused by the HPV virus, not to be confused with genital herpes (which is caused by the herpes simplex virus, HSV), or senile warts (seborrheic keratosis, a benign skin tumor of unknown etiology).
What are the main signs and symptoms of warts?
The presence of one or more round, raised, rough surfaces on the skin (usually on the hands or feet) can indicate the presence of warts. Warts can vary in appearance depending on their location on the body and the infecting HPV strain. They may have numerous small black dots on their surface, which are clotted blood vessels.[2][4] Although warts are often asymptomatic (other than the change in appearance of affected skin), they can have negative effects on quality of life by causing physical discomfort or psychological distress over cosmetic appearance.[3][4]
How are warts diagnosed?
Warts are diagnosed by health care providers during a clinical exam; diagnosis is based on their visual appearance.[5] If there is any doubt about the diagnosis, a skin biopsy may be collected and analyzed to rule out other types of skin growths, such as cancer.[5] Although PCR genotyping techniques can readily determine the specific HPV type(s) responsible for the infection, the specific infecting HPV strain does not affect the recommended treatment.[2][6]
What are some of the main medical treatments for warts?
For new warts, watchful waiting may be recommended instead of treatment, as many warts resolve on their own.[7] Otherwise, the main medical treatments for warts are topical medications, which are applied directly to the wart. Salicylic acid is often the first line of treatment, since it can be acquired without a prescription and has a cure rate of 50-70%, although it usually takes several weeks of application to work.[5] Cryotherapy is another first-line topical treatment, in which liquid nitrogen is applied directly to the wart. In addition to destroying the HPV-infected wart cells, the tissue damage caused by topical therapies stimulates the immune system, which may play a role in the eventual clearing of not only the treated wart, but warts at other sites in the body.[8][5][9]
How could diet affect warts?
Research on the impact of diet on warts is scarce. However, one area in which the effect of diet on the clearance of HPV infections has been studied is in the context of cervical cancer, which is caused by HPV. One observational study found an association between HPV resolution and higher total intake of whole fruits, seafood and plant protein.[14] While more research is needed, it is reasonable to assume that dietary habits with known positive effects on the immune system, such as high intake of fruits and vegetables,[15] could help either minimize the risk of getting warts or promote their clearance.
Are there any other treatments for warts?
In addition to the common topical treatments for warts, such as salicylic acid or cryotherapy, many other treatments have been used. However, not all of the following have been rigorously tested in randomized controlled trials, so high-quality evidence for their efficacy is currently lacking:[16]
- Topical agents with antiviral activity such as zinc, imiquimod, 5-fluorouracil, or acyclovir
- Intralesional bleomycin[17] (i.e., bleomycin injected directly into the wart)
- Candida antigen [17]
- Laser removal
- Curettage: warts are scraped off with an instrument
- Burning (electrocautery)
- Covering the wart with duct tape[18]
- Photodynamic therapy[4]
What causes warts?
Warts are caused by human papilloma virus (HPV). Although there are more than 150 strains of HPV, only a limited number cause warts.[2][5][19] HPV is spread through skin contact—either from body part to body part in the same individual, or from contact with other infected individuals. HPV can also spread by sharing objects that have come into contact with the virus, such as washcloths, towels, or clothing. Infections typically occur on areas of broken skin, where the skin barrier is compromised. Whether or not a wart will develop after exposure to HPV depends on the individual’s immune system, which may be able to fight off the HPV infection before a wart develops.
Examine Database: Warts
Frequently asked questions
Warts are small growths on the skin that are caused by the human papilloma virus (HPV). They generally appear as skin-colored bumps with a raised, rough surface. Although much of the time warts are harmless, and clear spontaneously within 1-2 years,[1] they may also require medical treatment depending on their location and symptoms.[2][3] Generally, warts are uncommon in infants, common in children, and decline in prevalence into adulthood.[4] It is important to note that warts are caused by the HPV virus, not to be confused with genital herpes (which is caused by the herpes simplex virus, HSV), or senile warts (seborrheic keratosis, a benign skin tumor of unknown etiology).
The presence of one or more round, raised, rough surfaces on the skin (usually on the hands or feet) can indicate the presence of warts. Warts can vary in appearance depending on their location on the body and the infecting HPV strain. They may have numerous small black dots on their surface, which are clotted blood vessels.[2][4] Although warts are often asymptomatic (other than the change in appearance of affected skin), they can have negative effects on quality of life by causing physical discomfort or psychological distress over cosmetic appearance.[3][4]
There are several different subtypes of warts, which are associated with infection with different variants of HPV.[5] Wart subtypes are generally classified based on appearance and the the area of the body affected.[20]
Common warts can appear anywhere on the body, but are often found on the hands.[20]
Genital warts are typically sexually transmitted and can appear on the genitals or in the space between the thighs. They can also form inside the vagina or anal canal. Although it has been estimated that 10-20% of the population may have genital HPV infections, only an estimated 1% develop genital warts.[23]
Plantar warts appear on the soles of feet, and are often painful, affecting walking or running. Plantar warts also tend to shed the HPV virus, which can spread to other regions of the skin or contaminate surfaces, potentially infecting other people.[24]
Mucosal papillomas are warts that appear on mucous membranes. They are white in appearance, and commonly affect the mouth, the vagina, or the conjunctival mucosa (the thin mucous membrane lining the inside of the eyelids).[25]
Subungual and periungual warts form under (subungual) or around (periungual) fingernails and toenails.
Flat warts are small (1-7 mm) fleshy growths that may be present in multiple numbers (up to hundreds). They tend to appear around the face and forehead. Flat warts are common in children but rare in adults.[5]
Warts are diagnosed by health care providers during a clinical exam; diagnosis is based on their visual appearance.[5] If there is any doubt about the diagnosis, a skin biopsy may be collected and analyzed to rule out other types of skin growths, such as cancer.[5] Although PCR genotyping techniques can readily determine the specific HPV type(s) responsible for the infection, the specific infecting HPV strain does not affect the recommended treatment.[2][6]
For new warts, watchful waiting may be recommended instead of treatment, as many warts resolve on their own.[7] Otherwise, the main medical treatments for warts are topical medications, which are applied directly to the wart. Salicylic acid is often the first line of treatment, since it can be acquired without a prescription and has a cure rate of 50-70%, although it usually takes several weeks of application to work.[5] Cryotherapy is another first-line topical treatment, in which liquid nitrogen is applied directly to the wart. In addition to destroying the HPV-infected wart cells, the tissue damage caused by topical therapies stimulates the immune system, which may play a role in the eventual clearing of not only the treated wart, but warts at other sites in the body.[8][5][9]
Whether a wart is treated or not depends on personal preference and symptoms. If the wart is not painful, has not spread, and is not present on an area of the skin that causes cosmetic or physical discomfort, simple observation may be an option, since up to two-thirds of warts go away by themselves within 2 years. For people seeking treatment, the least expensive and least painful treatments should be tried first.[5] One of the drawbacks to medical treatments is that they generally work by causing tissue damage, which can cause permanent scarring, whereas warts that resolve on their own generally do so without leaving a scar.[5]
It is important to see your doctor for an exam in following circumstances:[20][19]
- If the warts are located in the anal or genital areas: Warts in these areas may become cancerous, and need to be examined and treated by a physician.[5]
- If the appearance of a wart changes in color or increases in size: This could indicate the formation of abnormal, possibly precancerous cells that need to be evaluated.
- If the presence of a wart is painful, interferes with daily activities, or is cosmetically distressful.
- If warts begin to spread to more skin areas: This could indicate an immune system problem and should be checked out by a doctor.
Because there is no cure for HPV infection,[22] wart therapies can only eliminate signs and symptoms.[2] However, the HPV vaccine may be of some benefit, which is reflected in various case reports where individuals receiving the vaccine also resolved their warts. Although numerous wart treatments exist, their effectiveness at preventing wart recurrence is generally not great. Recurrence is common, especially when preventative measures are not followed and in people with weakened immune systems.[5][4]
Research on the impact of diet on warts is scarce. However, one area in which the effect of diet on the clearance of HPV infections has been studied is in the context of cervical cancer, which is caused by HPV. One observational study found an association between HPV resolution and higher total intake of whole fruits, seafood and plant protein.[14] While more research is needed, it is reasonable to assume that dietary habits with known positive effects on the immune system, such as high intake of fruits and vegetables,[15] could help either minimize the risk of getting warts or promote their clearance.
In addition to the common topical treatments for warts, such as salicylic acid or cryotherapy, many other treatments have been used. However, not all of the following have been rigorously tested in randomized controlled trials, so high-quality evidence for their efficacy is currently lacking:[16]
- Topical agents with antiviral activity such as zinc, imiquimod, 5-fluorouracil, or acyclovir
- Intralesional bleomycin[17] (i.e., bleomycin injected directly into the wart)
- Candida antigen [17]
- Laser removal
- Curettage: warts are scraped off with an instrument
- Burning (electrocautery)
- Covering the wart with duct tape[18]
- Photodynamic therapy[4]
Warts are caused by human papilloma virus (HPV). Although there are more than 150 strains of HPV, only a limited number cause warts.[2][5][19] HPV is spread through skin contact—either from body part to body part in the same individual, or from contact with other infected individuals. HPV can also spread by sharing objects that have come into contact with the virus, such as washcloths, towels, or clothing. Infections typically occur on areas of broken skin, where the skin barrier is compromised. Whether or not a wart will develop after exposure to HPV depends on the individual’s immune system, which may be able to fight off the HPV infection before a wart develops.
The following strategies can reduce the chances of getting warts:[20][19]
- Avoid contact with warts, including your own, which can spread HPV. If you come into contact with somebody else’s wart, thoroughly wash your hands as soon as possible. It is also important to avoid picking at warts, which could cause them to spread to other parts of your body.
- To avoid getting plantar warts, be sure to wear socks, shoes, or sandals when in public places such as locker rooms or swimming pools.
- Take care when clipping your fingernails or shaving, since damaging a wart can cause it to spread to other areas of the body.
- Avoid nail biting: nail biters tend to have a much greater incidence of periungual warts, often on multiple nails.[2]
Anybody with a weakened immune system—such as people with HIV/AIDS or graft recipients, who need to take immune-suppressing medications to prevent graft rejection—is at greater risk for getting warts. Children and young adults are also at higher risk, because they may not have had the chance to develop immunity to HPV through prior exposures.[19]
People who have previously had a wart are also at greater risk of getting additional warts in the future, compared to people who have never had warts.[21]
References
Examine Database References
- Wart Severity - Sharquie KE, Khorsheed AA, Al-Nuaimy AATopical zinc sulphate solution for treatment of viral wartsSaudi Med J.(2007 Sep)
- Wart Severity - Al-Gurairi FT, Al-Waiz M, Sharquie KEOral zinc sulphate in the treatment of recalcitrant viral warts: randomized placebo-controlled clinical trialBr J Dermatol.(2002 Mar)
- Wart Severity - Mun JH, Kim SH, Jung DS, Ko HC, Kim BS, Kwon KS, Kim MBOral zinc sulfate treatment for viral warts: an open-label studyJ Dermatol.(2011 Jun)