Suligoi et al.

BMC Infectious Diseases (2017) 17:126

DOI 10.1186/s12879-017-2202-6

RESEARCH ARTICLE Open Access

Prevalence and incidence of external

genital warts in a sample of Italian general
female population
Barbara Suligoi1*, Giorgio Vittori2, Maria Cristina Salfa1, Laura Timelli3, Dario Corsini3, Giovanni Fattorini4,
Luciano Mariani5 and the Genital Warts 2 (GW2) Working Group1

Abstract
Background: The Human papillomavirus is the most common sexually transmitted virus worldwide. The objective
of this study was to estimate: 1) the prevalence and the incidence of external genital warts (eGW) in a sample of
women attending community outpatient clinics and 2) the total number of eGW cases in the Italian female population
aged 15–64 years.
Methods: A prospective study was performed for a 12-month period between 2009 and 2010, among a sample of
women attending community gynecological outpatient clinics located throughout Italy. Demographic data, for every
woman aged 15–64 years, were collected. For women diagnosed with eGW, behavioral and clinical data were recorded.
Prevalence of eGW was calculated as the proportion between the number of women with eGW and that of women
visiting any of the participating gynecologists; incidence of eGW was calculated as the proportion between the number
of women with a new diagnosis of eGW and that of women visiting any of the participating gynecologists. Standardized
prevalence by age was used to estimate the number of eGW cases occurring in the Italian female population
aged 15–64 years.
Results: In 2009–2010, 44 community gynecologists were included in the network. In one-year period, 16,410
women visited any of the participating gynecologists; 63 women were diagnosed with eGW, corresponding to a
prevalence of 3.8 cases per 1,000 women per year (95%CI: 2.9-4.9). The incidence of eGW was 3.0 cases per 1,000
women per year (95%CI: 2.2-3.9). Women aged 15–24 years showed both the highest prevalence and incidence.
Prevalence and incidence significantly decreased by increasing age group (p <0.001), and were higher in Southern Italy
compared to Central-Northern Italy. The estimated number of women with eGW among women aged 15–64 years in
Italy, in 2010, was approximately 69,000.
Conclusions: These data show a high prevalence and incidence of eGW among young women in Italy, stress the
effectiveness of community clinical networks in investigating STI epidemiology among women from the general
population, confirm the relevance of HPV vaccination programs among adolescents, and underscore the need of
promoting safe sex, implementing early diagnosis, treatment and prevention of genital warts.
Keywords: External genital warts, Women, Community gynecologists, Prevalence, Incidence, Italy

* Correspondence: barbara.suligoi@iss.it
1
Centro Operativo AIDS, Istituto Superiore di Sanità, Viale Regina Elena 299,
Rome, Italy
Full list of author information is available at the end of the article

© The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
Suligoi et al. BMC Infectious Diseases (2017) 17:126 Page 2 of 8

Background a sample of women attending community gynecological

The Human papillomavirus (HPV) is the most common outpatient clinics located throughout Italy (i.e. North,
sexually transmitted virus worldwide. Among the more Center, and South).
than 200 different types of HPV identified so far, more The sample selection was based on a two sampling stage
than 40 types are responsible of infections in the genital strategy: first, the selection of community gynecologists
area, causing both benign and malignant lesions [1–3]. and second, the number of women visited in one year by
The most common benign genital HPV infection are each community gynecologist.
genital warts, caused in about 90% of the cases by HPV
type 6 and 11 [4, 5]. Genital warts affect both males and The network of community gynecologists
females; in Europe, there is an approximate burden of SIGO together with the support of the Italian Associ-
500,000 cases divided almost equally between both ation of Territorial Gynecologists (AGITE) in the first
sexes, although slightly higher in men according to latest phase identified 30 gynecologists to act as regional coor-
data [6]. dinators, including at least one coordinator from each of
In Europe, genital warts are subject to mandatory noti- the 20 Italian regions. The study coordinators trained
fication only in the United Kingdom [7]. In other coun- the regional coordinators on the study methods and data
tries, the information on the spread of this disease is collection procedures.
derived from epidemiological studies, sales of medicines In the second phase, a list of 485 community gynecol-
specifically used for the treatment of genital warts, or ogists was obtained from the 30 lists provided by the
surveillance of sexually transmitted infections (STI) [6]. regional coordinators. From this list, 320 community gy-
In Italy, women with external genital warts (eGW) are necologists were randomly selected and invited to par-
usually diagnosed and treated in gynecological services ticipate in the study. Of these, 44 accepted to participate
and sexually transmitted infection (STI) clinics. The sen- in the study. The regional coordinators trained the 44
tinel STI surveillance system based on STI clinics and community gynecologists who were residing in 13 of the
two epidemiological studies provided data on eGW in 20 Italian regions.
Italy so far [8–10]. However, information obtained from As previously described [12], to be part of the net-
the sentinel STI surveillance system, although covering work, the community gynecologists needed to comply
24 years of data collection and being essential for moni- with the following requirements:
toring trends in time, is not suitable for estimating
prevalence and incidence of single STIs in that denomi-  to dedicate part of their professional practice to
nators for calculating these measures are not available. first-level consultations (they see new patients and
Moreover, STI clinics collect data on symptomatic do the first diagnosis of the disease, they are the first
patients who are not representative of the population at doctors/physician the patients seeks for help) or
large [8]. In Italy, about 66% of women between 18 and referral consultations (patients are referred from
55 years of age undergo every year a gynecological visit other specialists for diagnosis confirmation and
in a public and/or private gynecological setting [11]. treatment), in either private or public practice;
The launch of the HPV vaccination campaign in Italy  to possess a personal computer with internet
in 2008 emphasized the debate about the cost/benefit of connection;
HPV vaccination at National level and underscored the  to have at least 200 women visiting the clinic in one
lack of prevalence/incidence data on genital warts that year;
would be valuable as first-line efficacy indicators of the  to participate without any economic benefit.
vaccination campaign.
Taking into account this background, the Istituto Sample size calculation
Superiore di Sanità (ISS) and the Italian Society of Standard statistical methods used for sample size esti-
Gynecology and Obstetrics (SIGO) decided in 2009 to mate and analysis do not include the between-clusters
conduct a prospective study to estimate the prevalence component of variability in the outcome and conse-
and the incidence of eGW in a sample of women attend- quently cannot be applied in cluster-based studies be-
ing community gynecological outpatient clinics and the cause they would provide sample sizes that are too small
total number of women with eGW among women aged [13]. In fact, in this case the variability of the studied
15–64 years in Italy. phenomenon depends on two components: the variabil-
ity within the cluster (i.e. difference in the frequency of
Methods eGW diagnosis between women visited by the same
Study design and sampling method community gynecologist) and the variability between
A prospective study was performed for a 12-month clusters (i.e. differences between women visiting differ-
period between November 2009 and December 2010, in ent community gynecologists). The within-cluster and
Suligoi et al. BMC Infectious Diseases (2017) 17:126 Page 3 of 8

between-clusters components of variability can be com- Early recurrent cases of eGW (recent relapse) included
bined in a single statistical measure of between-clusters women who reported episodes of eGW in the previous
heterogeneity (or within-cluster homogeneity), namely 12 months.
the Intraclass correlation coefficient (ICC). Late recurrent cases of eGW (late relapse) included
As previously described [12], to calculate the sample women who reported prior episodes of eGW but did not
size, the following parameters were taken into account: suffer from any recurrence in the previous 12 months.

 the average number of women visiting any Data collected

community gynecologist in one year; Participating gynecologists reported essential individual
 the expected incidence of eGW; socio-demographic data (i.e. age, nationality, and ethni-
 the ICC. city) and medical history (i.e. self-reported anti-HPV
vaccination status; vaccination with bivalent or quadriva-
Particularly, we assumed that the incidence of eGW in lent vaccine; number of pregnancies) for every woman
Italy was expected between 1 and 5 per 1,000 [9]. No esti- aged 15–64 visiting the gynecologist for any reason.
mate of the expected ICC in studies performed among For women diagnosed with eGW the following additional
Italian gynecologists was available; therefore, we used sev- information was recorded: level of education, self-reported
eral estimates of ICC obtained from 16 datasets covering a behavioral data (age at first sexual intercourse, previous STI
range of diseases for health binary outcomes [9, 14]. lifetime, concurrent diseases, use of contraceptives in the
Finally, we performed a simulation varying the median previous 12 months, number of partners in the previous
number of women visiting the same community 12 months), clinical data (current genitourinary symptoms
gynecologist, the expected ICC, and the width of the 95% such as itching, vaginal discharge, dispareunia), written re-
confidence interval (95%CI) around the expected inci- sult of HIV test, reason of the consultation, type of medical
dence of eGW. We observed that the number of commu- or surgical treatment of eGW and outcome of the
nity gynecologists to be included and, consequently, the treatment.
number of women included increased with increasing ICC
(independently from the median number of women visited Data input
per community gynecologist), and conversely decreased The collection and management of data were made elec-
with increasing 95%CI width (regardless of the ICC). tronically through the SIGO website. Each community
gynecologist accessed the dedicated area containing data
Inclusion and exclusion criteria collection forms. Data collection forms filled by every
Women meeting the following inclusion criteria were in- community gynecologist were conveyed at the Contract
cluded [12]: Research Organization (CRO) data center where data
management and analyses were performed. A tailored
 age from 15 to 64 years; data collection software performed consistency and
 permanent residence in Italy (regardless of completeness checks on the data. The CRO performed
nationality); periodical controls on the congruency and completeness
 visited the gynecologist at least once in a one-year of data entered by gynecologists.
period.
 The exclusion criteria were: Measures of frequency
 not having a permanent residence in Italy. Prevalence of eGW was calculated as the proportion be-
tween the number of women with eGW and that of
Definition of eGW women visiting any of the participating gynecologists for
According to Cartier’s definition [15], eGW were defined any reason in 2009–2010. Incidence of eGW was calcu-
as flesh-colored, exophytic lesions (small bumps, flat, ver- lated as the proportion between the number of women
rucous, peduncolated, raised papules or dome-shaped le- with a new diagnosis of eGW and that of women visiting
sions on keratinized skin) on the external genitalia, any of the participating gynecologists for any reason in
including vulva, perineum, and perianal skin. The diagno- 2009–2010.
sis of eGW was based on visual inspection. In order to Ninety five percent confidence intervals (95%CI) were
standardize inter-observer variation in the diagnosis of calculated using binomial distribution. Prevalence and
eGW and HPV-related lesions a two-day special training incidence were also analyzed stratifying by age group
course was held. (15–24, 25–34, 35–44, 45–64 years) and geographical
Newly diagnosed cases of eGW included women diag- area of residence (Northern, Central, Southern Italy).
nosed with eGW who reported never having had eGW Comparisons between age groups or geographical areas
before. were performed using the chi-square test. Age-specific
Suligoi et al. BMC Infectious Diseases (2017) 17:126 Page 4 of 8

rates were used to calculate standardized prevalence and Table 1 Socio-demographic and behavioral characteristics of 63
incidence using as reference Italian [16] and European women with eGW
standard population [17] aged 15–64 years. Age-specific Characteristic Women with eGW (n = 63)
rates were used also to estimate the number of eGW cases N %
in the Italian female population aged 15–64 years multi- Education
plying the estimated prevalence by the underlying female None
population. For the analysis of data, SaS.8.2 was used.
Primary school 12 19.1

Results Middle school 9 14.3

In one-year period, 16,410 women, who represented 0.1% High school 25 39.7
of the total female Italian population aged 15–64 years, University degree 17 26.9
visited any of the 44 community gynecologists included in na°
the network. Their median age was 37 years (inter quartile Current pregnancy
range 29–47 years); 10.5% were pregnant; 12.5% were mi-
yes 7 11.1
grants: of these, 56.0% were Caucasians, 17.0% Hispanic,
15.0% Asian, 11.0% African and 1.0% of other ethnicities. no 56 88.9
Fifty women had been vaccinated for HPV; of these, na°
30 with the bivalent vaccine, 9 with the quadrivalent vac- Number of sexual partners in previous 12 months
cine, and the type of vaccine was not reported for 11 0 26 41.3
women. 1 30 47.6
There were 63 women diagnosed with eGW. Socio-
≥2 7 11.1
demographic and behavioral characteristics of these
women are shown in Table 1. The median age at first na°
sexual intercourse was 17 years (inter quartile range: Current genitourinary symptoms
15–20 years). Ten women (16.0%) reported having had yes 32 50.8
previous bacterial genital infections without specifying no 31 49.2
the etiological agent; one woman reported having had na°
genital herpes, and one Chlamydia trachomatis
Contraceptive use in previous 12 months
infection.
Moreover, 13.0% of women with eGW reported having None
been tested for HIV at least once in a lifetime; none of Condom 16 25.4
them was HIV positive. No woman with eGW had been Oral contraceptive 11 17.5
HPV-vaccinated. Other 13 20.6
Among women with eGW, the most frequent reasons na° 35.5
for consultation were as follows: presence of genital warts
°na: not available
(36.0%), check-up not related to eGW (35.0%; includes op-
portunistic cytology screening, annual check-up, post-
treatment follow-up, family planning), self-reported genital Among the 63 women diagnosed with eGW, 49 were
symptoms (11.0%), pregnancy (10.0%), menopause (5.0%), new diagnoses corresponding to a crude incidence of 3.0
and use of oral contraceptives (5.0%) (these categories cases per 1,000 women per year (95%CI: 2.2-3.9)
were not mutually exclusive). (Table 3). Eight women had a recurrent eGW; of these, 4
The crude prevalence of eGW was 3.8 cases per 1,000 had a late relapse and 4 had a recent relapse (corre-
women per year (95%CI: 2.9-4.9) (Table 2). sponding in both cases to an incidence of 0.2 cases per
The highest prevalence of eGW was observed among 1,000 women per year, 95%CI: 0.1-0.6). For 6 women
25–34 year-old women living in the South. Prevalence this clinical information was not reported.
decreased by increasing age group: this decrease was sig- The crude incidence of eGW significantly decreased
nificant even though 95%CI overlapped (p <0.001) [18] by increasing age group (p <0.001). The highest inci-
(Table 2). When combining data of women living in the dence was observed among 25–34 year-old women liv-
North with those of women living in the Center (to ing in the South and 45–64 year-old women living in the
reach statistical significance), the prevalence of eGW North. The incidence of eGW was higher among women
was significantly higher among women living in the living in Southern Italy compared to those living in
South (5.4‰ vs. 2.5‰, p = 0.003). The prevalence of Central-Northern Italy (3.9‰ vs 2.2‰, p = 0.036). The
eGW among Italian and migrant women was not signifi- incidence of eGW among Italian and migrant women
cantly different (3.9‰ vs. 3.4‰, p = 0.733). was not significantly different (3.4‰ vs 2.9‰, p = 0.710).
Suligoi et al. BMC Infectious Diseases (2017) 17:126 Page 5 of 8

Table 2 Crude prevalence of eGW, by age group and location (per 1,000)
Age Women Women Prevalence (‰) (95% CI)
group with visiting the
Total North Center South
eGW gynecologist
(number) (number)
15–24 18 2,491 7.2 (4.3-11.4) 8.3 (4.2-14.9) 0.0 (0–38.8) 6.5(1.6-13.9)
25–34 27 4,331 6.2 (4.1-9.1) 2.6 (1.0-5.7) 3.8 (0.1-21.1) 11.3 (6.9-17.5)
35–44 11 4,482 2.5 (1.2-4.4) 0.8 (0.1-3.0) 0.0 (0–15.8) 8.3 (4.2-14.9)
45–64 7 5,106 1.4 (0.6-2.8) 8.3 (4.2-14.9) 0.0 (0–13.9) 4.9 (2.3-9.4)
Total 63 16,410 3.8 (2.9-4.9) 2.6 (1.6-4.0) 1.2 (0.0-6.5) 5.4 (3.9-7.3)
p < 0.001 by age group; p = 0.003 North + Center vs. South

The age-standardized prevalence and incidence of eGW the present study was higher also when compared to that
using Italian female population as reference were 3.4 (95% emerged in studies based on women attending general
CI: 2.6-4.3) and 2.7 (95% CI: 1.9-3.4) cases per 1,000 women practitioners (GP), which ranged between 0.51 and 0.59
aged 15–64 years, respectively. Using the European female cases per 1,000 women [10, 13, 22]. At least in the Italian
standard population as reference, these measures were 3.6 context, the network of community gynecologists is likely
(95% CI: 2.7-4.5) and 2.8 (95% CI: 2.0-3.6), respectively. to be more accurate in estimating the frequency of eGW
Using the age-specific rates of the Italian female popula- among women than the GP network. The reason being
tion, we estimated that there were about 69,000 women that in Italy women with eGW primarily seek treatment
with eGW aged 15–64 years in Italy, in 2010. with a gynecologist rather than a GP [10], similarly to
what reported in England where about 70% of patients
Discussion with eGW were seen only in genitourinary medicine
This prospective study estimated the prevalence and the clinics [13].
incidence of eGW in a sample of women attending com- Conversely, the eGW prevalence estimated in this study
munity gynecology outpatient clinics in Italy. was much lower than that reported in a retrospective
These data are similar to those reported in a retro- study based on a self-administered questionnaire, con-
spective Italian study conducted among community gy- ducted in 70,000 women of four northern European coun-
necologists [9]. tries (Norway, Sweden, Denmark and Iceland) which
The prevalence of eGW estimated in the present study reported a prevalence of 13 cases per 1,000 women [23].
(3.8 cases per 1,000) is slightly higher compared to that re- Indeed, retrospective studies based on self-administered
ported in studies conducted in other European countries questionnaire may overestimate the frequency of GW due
in various clinical settings. In England, the prevalence of to a methodological bias, in that women with a history of
eGW was 2.3 cases per 1,000 in a sample of women at- GW would be more prone to answer to the questionnaire.
tending genitourinary medicine clinics [13]. In France, it The incidence of eGW observed in this study is similar
was 2.3 cases per 1,000 in a sample of women attending to that reported in other studies conducted in France
French public gynecologists [14]. In Spain, it was 1.6 cases [14] and the UK [22], but higher compared to that re-
per 1,000 women [19] and in Germany 1.5 cases per 1,000 ported in other European countries, such as Spain [19]
women [20] attending various medical specialists. In and Germany [20].
Canada, it was 1.4 per 1,000 women based on data col- Compared to estimates reported in a systematic review
lected by STI clinics, pharmacists, physicians billing data- [24], our prevalence and incidence rates are higher than
base and hospitalizations [21]. The prevalence found in those reported in other countries. These diversities can

Table 3 Crude incidence of eGW, by age group and location (per 1,000)
Age Women Women Incidence (‰) (95% CI)
group with visiting the
Total North Central South
eGW gynecologist
(number) (number)
15–24 15 2,491 6.0 (4.3-11.4) 6.8 (3.1-13.0) 0.0 (0–38.8) 5.6 (2.0-12.1)
25–34 21 4,331 4.8 (4.1-9.1) 2.1 (0.7-5.1) 3.8 (0.1-21.1) 8.5 (4.8-14.0)
35–44 8 4,482 1.8 (1.2-4.4) 0.8 (0.1-3.0) 0.0 (0–15.8) 3.3 (1.2-7.1)
45–64 5 5,106 1.0 (0.6-2.8) 8.3 (4.2-14.9) 0.0 (0–13.9) 1.3 (0.3-3.8)
Total 49 16,410 3.0 (2.2-3.9) 2.3 (1.3-3.6) 1.2 (0.0-6.5) 3.9 (2.7-5.6)
p < 0.001 by age group; p = 0.036 North + Center vs. South
Suligoi et al. BMC Infectious Diseases (2017) 17:126 Page 6 of 8

be attributed to a number of reasons, such as: a different women were not comprised in the vaccination campaign
age range of the study population (15–64 years in our but rather purchased the vaccine on their own.
sample vs. larger age ranges in other studies), a different Our estimated number of about 69,000 women with
background of the study population (women visiting a eGW aged 15–64 years in Italy in 2010, would imply
community gynecologist in our study vs. general popula- that our sample is representative of all Italian women
tion or privately-insured women in other studies), or a and that all women visit a gynecologist routinely. How-
different recruitment setting (community gynecologists ever, we know that around 66% of Italian women aged
in our study vs. cytology screening services or GP in 18–55 years visit a gynecologist annually [11]. Therefore,
other studies). assuming that women who do not visit a gynecologist
We observed the highest prevalence and incidence of annually be free from eGW, then an adjusted estimate of
eGW was observed among 15–24 year-old women com- the total number of women aged 15–64 with eGW
pared to women older than 25 years of age, similarly to would be approximately 45,500 (i.e., 69,000 x 0.66). This
what reported in other studies [14, 20–22, 24]. This finding figure should be considered as a minimum estimate,
has been associated with higher levels of sexual activity with which implies that among the 34% of women who do
multiple partners and low viral immunity in this age group not visit a gynecologist none is suffering from eGW.
[2]. Previous studies conducted in Italy have shown the de- Some limitations of this study should be addressed. The
terminant role of multiple sex partners in the prevalence of main limitation was the small number of community gyne-
genital HPV infection among young women [25, 26], thus cologists who accepted to participate, which was probably
underscoring the main relevance of HPV vaccination attributable to the free and unpaid participation in the net-
among adolescent females. Interestingly, our results show a work. Another limitation was the lack of geographic repre-
second peak in prevalence and incidence among women sentativeness of the participating gynecologists that resided
aged 45–64 years living in the North; this U-shaped curve in only 13 of the 20 Italian regions. Finally, our network of
has been reported in Southern Europe and may be related community gynecologists, though composed of generalist
to immuno-senescence, perimenopausal hormonal changes, gynecologists, may have concentrated a population at
changes in male/female sexual behavior, cohort effects, or higher risk of eGW in the study period due to the estab-
higher rates of HPV persistence at older ages [27]. lished general experience of these gynecologists.
Compared to the general female Italian population Our surveillance network of community gynecologists
[16], our sample was younger (age group 25–34 years: shows several strengths. First, a low cost as the participa-
26.4% vs 19.2%), with a higher proportion of migrant tion of gynecologists in the network was voluntary with-
(12.5% vs 8.5%) and pregnant women (10.5% vs 1.6%). out any economic compensation. Second, women enrolled
Age-specific standardization was applied to adjust preva- in the study were not selected by the presence of specific
lence and incidence rates for differences in age distribu- symptoms and included both symptomatic and asymp-
tion. The higher proportion of migrant or pregnant tomatic patients attending for a routine visit or annual
women in our study sample may have had an impact on check-up, unlike STI specialists that see mainly symptom-
the observed prevalence in that both populations have atic patients. Third, participating gynecologists were ad-
been reported to have a higher probability of HPV equately trained on genital warts and could provide
infection compared to Italian or non-pregnant women reliable diagnosis and follow-up of patients. Fourth, com-
[28, 29]. Moreover, previous studies have evidenced a munity gynecologists collected essential data on the num-
higher HPV prevalence among migrant women in ber and the characteristics of visited women, providing
Southern Italy [29, 30], which can explain the higher the denominator required for estimating the burden of
prevalence and incidence of eGW found among women eGW in terms of frequency, incidence and prevalence.
living in the South. Fifth, the user-friendly data-collection software facilitated
In Italy, the national HPV vaccination campaign input and linkability of patient’s longitudinal data, allow-
started in 2008 and targeted 12 years-old girls [31]. Our ing also for real-time transmission of data. Sixth, all infor-
study was conducted in the two years following the im- mation was centralized thus optimizing data management
plementation of the HPV vaccination program and in- and analysis.
cluded women aged ≥15 years which did not allow
detecting any impact of the vaccination campaign on Conclusions
study participants. Nevertheless, our results provide es- This prospective study was based on an innovative sur-
sential epidemiological data that can be used as baseline veillance network composed of a sample of community
for future studies aimed at evaluating the effectiveness gynecologists located in 13 Italian regions.
of the Italian HPV vaccination campaign. Our study These data stress the effectiveness of community clin-
sample included a number of HPV-vaccinated women ical networks in investigating STI epidemiology among
and none of them was diagnosed with eGW: these women from the general population, promoting safe sex
Suligoi et al. BMC Infectious Diseases (2017) 17:126 Page 7 of 8

and implementing early diagnosis, treatment and preven- Consent for publication
tion. Moreover, this study provides evidence of the para- Not applicable.

mount importance of HPV vaccination among adolescents,

which has already proved to reduce dramatically the inci- Ethics approval and consent to participate
Detailed clinical data were collected only for eGW cases. All the subjects
dence of GW in several countries [32]. Indeed, although were informed about the procedures and data handling and all participants
GW represent a benign condition, treatment costs and im- signed a consent form before participating. The study and the related
pact on psycho-sexual life enforce the need of preventing documents were notified to the Ethics Committee of the National Institute
of Health (ISS) that gave his favorable opinion.
the occurrence of these lesions.
Abbreviations Author details
1
AGITE: Italian association of territorial gynaecologistsGynecologists; CRO: The Centro Operativo AIDS, Istituto Superiore di Sanità, Viale Regina Elena 299,
contract research organization; eGW: External genital warts; GP: General Rome, Italy. 2Ospedale San Carlo di Nancy, Via Aurelia 275, Rome, Italy.
3
practitioners; GW: Genital warts; HPV: Human papillomavirus; ICC: Intraclass Informa srl, Via Luigi Rava 43, Rome, Italy. 4Associazione ginecologi
correlation coefficient; ISS: Istituto superiore di sanità; SIGO: The Italian territoriali (AGITE), Via G. Abamonti 1, Milan, Italy. 5HPV-unit, Istituto Nazionale
society of gynaecology and obstetrics; STI: Sexually transmitted infections Tumori Regina Elena, Via Elio Chianesi 53, Rome, Italy.

Acknowledgements Received: 18 June 2016 Accepted: 12 January 2017

Not applicable
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