Human 
Papillomavirus: 
HPV Information 
for Clinicians 
 Transmission 
 Prevention 
 Detection 
 Clinical Management 
Centers for Disease Control and Prevention 
April 2007 

Contents 
Section I: Genital HPV Infection .........................................1 
About HPV .............................................................................1 
Table 1: Types of HPV ......................................................2 
Table 2: Factors Associated with HPV Infection ..............3 
HPV Transmission .................................................................3 
HPV Natural History ..............................................................4 
HPV-associated Outcomes ...................................................7 
HPV Prevention .....................................................................9 
HPV Detection .....................................................................13 
Section II: Cervical Cancer Prevention ............................15 
Table 3: Cervical Cancer Screening Guidelines .............16 
Screening with Cervical Cytology .......................................18 
HPV Testing for High-Risk Types .........................................19 
Cervical Cancer Screening Management Algorithms ....20 
Section III: Genital Warts ..................................................23 
Diagnosis .............................................................................23 
Treatment .............................................................................24 
Table 4: Recommended Treatment ...............................24 
Special Considerations for Women .....................................25 
Section IV: References .....................................................26
 

Why is it 
Important 
to Know 
About HPV? 
Genital infection with human 
papillomavirus (HPV) is the most 
common sexually transmitted 
infection (STI) in the United 
States (U.S.) today.1 Over half of 
sexually active women and men 
are infected with HPV at some 
point in their lives.2 
In most cases, infections with 
HPV are not serious. Most HPV 
infections are asymptomatic, 
transient, and resolve without 
treatment. However, in some 
individuals, HPV infections 
result in genital warts, Pap test 
abnormalities, or, rarely, cervical 
cancer.3 
The Pap test is useful in early 
detection of cervical cancer, one 
of the possible outcomes of an 
HPV infection. Early detection 
and treatment of pre-cancerous 
lesions can prevent development 
of cervical cancer.4 
What is HPV? 
Papillomaviruses are DNA tumor 
viruses that are widely distributed 
throughout animal species; 
these viruses are species specific. 
The papillomavirus 
that infects humans is called 
human papillomavirus, or HPV. 
HPV commonly causes epithelial 
proliferations at cutaneous and 
mucosal surfaces. 
Types of HPV 
There are more than 100 different 
types of HPV. They differ in terms 
of the types of epithelium they 
infect. Some infect cutaneous 
sites, whereas others infect 
mucosal surfaces. 
Over 40 types infect mucosal 
surfaces, including the anogenital 
epithelium (e.g., cervix, vagina, 
vulva, rectum, urethra, penis, 
and anus). For most of these 
HPV types, there are sufficient 
data to divide them into 
high-risk (e.g., oncogenic or 
cancer-associated) types and 
low-risk (e.g., non-oncogenic) 
types (see Table 1 on page 2). 
How Common is HPV? 
Approximately 20 million 
Americans 15 to 49 years of 
age (approximately 15% of the 
population) are currently infected 
with HPV.5 Others may have been 
infected in the past and may 
no longer have the virus. About 
half of those who are infected 
with HPV are sexually active 
adolescents and young adults 15 
to 24 years of age.5 Between 5% 
and 30% of individuals infected 
with HPV are infected with 
multiple types of HPV.6 
HPV Infection 
Section I: Genital HPV Infection

 Each year, about 6.2 million 
people in the U.S. become 
newly infected.1 
 Estimates for the incidence 
and prevalence of genital warts 
caused by low-risk types of 
HPV are imprecise. About 1% 
of sexually active adults have 
visible genital warts at any 
point in time.7 
Table : Types of HPV 
High-risk 
(oncogenic or cancer-associated) 
types 
Common types: 
16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 
59, 68, 82
These are considered high-risk because 
they can be found in association with 
invasive cancers of the cervix, vulva, 
penis, or anus (as well as other sites). 
 HPV 16 is the most common high-risk 
type, found in almost half of all cervical 
cancers. It is also one of the most 
common types found in women 
without cancer.8 
 HPV 18 is another common high-risk 
virus, found not only in squamous 
lesions but also in glandular lesions of 
the cervix. HPV 18 accounts for 10% 
to 12% of cervical cancers.8 
All of the other high-risk types can be 
associated with cervical cancer, but much 
less frequently than HPV 16 and 18. HPV 
types 31, 33, 45, 52, and 58 each account 
for between 2% to 4% of cancers. Each of 
the other high-risk types account for 1% 
or less of cancers.9  

Low-risk 
(non-oncogenic) 
types 
Common types: 
6, 11, 40, 42, 43, 
44, 54, 61, 72, 
73, 81 
These can cause 
benign or lowgrade 
cervical cell 
changes and genital 
warts but are rarely, 
if ever, found in 
association with 
invasive cancers. 
 HPV 6 and 
HPV 11 are the 
low-risk viruses 
that are most 
commonly found 
in genital warts.8

Table 2: Factors Strongly Associated with 
Acquisition of HPV Infection in Women , 0, , 
A number of prospective studies conducted primarily in young 
women have defined the risk factors for HPV acquisition. 
 Young age (less than 25 years) 
 Increasing number of sex partners 
 Early age at first sexual intercourse (16 years or younger) 
 Male partner has (or has had) multiple sex partners 
HPV Infection

How is 
Genital HPV 
Transmitted? 
HPV is usually transmitted 
through direct skin-to-skin 
contact, most often during 
penetrative genital contact 
(vaginal or anal sex). Other 
types of genital contact in 
the absence of penetration 
(oral-genital, manual-genital, 
and genital-genital contact) 
can lead to HPV infection, but 
those routes of transmission 
are much less common than 
sexual intercourse.13 
Genital HPV infections are 
uncommon in women reporting 
no previous sexual intercourse, 
appearing in less than 2% of 
this population.13, 14, 15 
Sexual behavior is the most 
constant predictor of acquiring 
infection. Most importantly, 
the number of sex partners is 
proportionately linked to the 
risk of HPV infection.10, 11, 13 
Having sex with a new partner 
may be a stronger risk factor 
for initial HPV acquisition 
than having sex with a 
steady partner.13, 16 
For women, the sexual activity of 
their partner(s) is also important 
for determining risk of HPV 
acquisition. For adolescent 
females and college students, 
the risk of acquiring HPV is 
increased if a womans partner 
has had or currently has other 
partners.16 
HPV infections are also common 
in men who have sex with men 
(MSM) and women who have sex 
with women.17 HPV DNA can be 
detected in swabs from the anal 
canal in over 50% of MSM.18 
HPV infection can be detected 
on inanimate objects, such 
as clothing or environmental 
surfaces. However, transmission 
is not known to occur by 
this route.19, 20 

Natural 
History of 
Genital HPV 
Infections 
Most genital HPV infections are 
transient and asymptomatic. 
Approximately 70% of women 
with HPV infections become 
HPV DNA negative within 
one year, and as many as 
91% of them become HPV 
DNA negative within two 
years.10, 16, 21, 22 The median 
duration of new infections is 
typically eight months.10 
HPV 16 infections tend to persist 
longer than infection with other 
HPV types, but most HPV 16 
infections become undetectable 
within two years.10 
The gradual development of 
an effective immune response 
is thought to be the likely 
mechanism for HPV DNA 
clearance.4 However, it is also 
possible that the virus remains in 
a non-detectable dormant state 
and then reactivates many years 
later. This may explain why HPV 
may be newly detected in some
older women who have been in a 
long-term mutually monogamous 
relationship.1  

The Three Steps of Cervical Carcinogenesis
Transient Infection
1.HPV 
Initial infection
Normal cervix 
Clearance
2. Mild cytologic abnormalities 
HPV-infectied cervix 
Progression 
Regression
3.Persistent HPV Infection
Pre-cancerous lesion  
Invasion 
Cancer
The steps can be conceptualized as infection with specific 
high-risk types of human papillomavirus (HPV), progression 
to a precancerous lesion, and invasion. HPV infections are 
usually transient and are often associated with mild cytologic 
abnormalities. Persistent infection with high-risk types of HPV is 
uncommon and is required for progression. 
Reprinted from Adding a test for human papillomavirus DNA to cervical-cancer screening. 
Wright TC and Schiffman M. New England Journal of Medicine 2003 Feb 6; 348(6): 489-490. 
Copyright 2003 Massachusetts Medical Society. All rights reserved. 

Many women with transient HPV 
infections may develop atypical 
squamous cells of undetermined 
significance (ASC-US) or lowgrade 
squamous intraepithelial 
lesions (LSIL), as detected 
on a Pap test. These are mild 
cytologic abnormalities that 
represent the cytopathic effect 
caused by HPV infection, and 
they may spontaneously regress. 
Only about 10% of women 
infected with HPV develop 
persistent HPV infections.23 
Women with persistent high-risk 
HPV infection are at greatest 
risk for developing high-grade 
cervical cancer precursors and 
cancer. The risk of developing 
moderate to severe dysplasia, 
or grades 2 or 3 cervical 
intraepithelial neoplasia (CIN 
2, 3) lesions, for women with 
persistent high-risk HPV infection 
is not well defined. However, 
the risk is greater than that of 
women whose infections clear 
spontaneously.24, 25 
Currently, there are no data 
available on the natural history 
of HPV infection in men. 

Top Image: The epithelium of the CIN 1 lesion is 
thickened and the upper layers contain 
cells characterized by perinuclear halos, 
multinucleation, and significant nuclear atypia. 
Such cells are referred to as koilocytes. 
Bottom Image: This high-powered magnification of 
a CIN 1 lesion shows the nuclear irregularities 
typically seen in koilocytes. 
HPV Infection

Factors Influencing 
HPV Persistence 
and Progression to 
Cervical Cancer
 
Several risk factors have been 
identified that appear to be 
associated with HPV persistence 
as well as progression to cervical 
cancer. The single most 
important factor associated 
with invasive cervical cancer 
is the factor of never or rarely 
being screened for cervical 
cancer. The National Institutes 
of Health (NIH) estimates that 
half of the women who receive 
cervical cancer diagnoses have 
never been screened for cervical 
cancer and that an additional 
10% have not been screened in 
the previous five years.4 

Immunosuppression from any 
cause, including HIV infection, 
is recognized to increase HPV 
persistence and to be associated 
with increased risk of invasive 
cervical cancer.22, 26 

Cigarette smoking has been 
associated with HPV persistence 
and risk of cervical cancer. 
Multiple case-control studies 
show a moderate and statistically 
significant association between 
smoking and cervical cancer, 
even after adjusting for the 
effects of HPV.27
 
Other epidemiologic factors 
associated with risk of cervical 
cancer include long-term 
use of oral contraceptives,27 
co-infections such as 
Chlamydia,28 parity, and 
nutritional factors.29, 30, 31, 32
 
However, in populations that are 
screened regularly, as is typical 
in the U.S., cervical cancer 
develops rarely in women, even 
with persistent HPV infection. 
This is because women with 
high-grade precursor lesions 
are usually identified through 
cytologic screening, and the 
development of cancer can 
be prevented through early 
detection and treatment.

What are 
Potential 
Outcomes 
Associated 
with Genital 
HPV Infection? 

Most HPV infections are 
asymptomatic, and they resolve 
without treatment. However, 
some infections result in changes 
to the epitheliumor cancer. 

Women
 
Genital infection with low-risk 
types of HPV is associated with 
genital warts in women.
 
Persistent infection with highrisk 
types of HPV is associated 
with almost all cervical cancers 
and many cancers of the vulva, 
vagina, and anal regions. 
However, the risk for anal, 
vulvar, and vaginal cancers is 
considerably less than the risk 
for cervical cancer.
 
In 2002 (most recent year for 
which data are available), the 
age-adjusted incidence rate* 
for invasive cervical cancer in 
the U.S. was 8.7 per 100,000 
women (12,085 new cases). In 
comparison, the age-adjusted 
incidence rates for anal, vulvar, 
and vaginal cancers were 1.5, 
2.3, and 0.7 per 100,000 women, 
respectively.33
 
While infection with highrisk 
HPV is necessary for the 
development of cervical cancer, 
most infections do not result in 
cancer.
 
Women with HPV infection 
who spontaneously clear their 
infection and continue to be HPV 
DNA negative appear to be at 
very low risk for subsequently 
developing cervical cancer. 

* The number of new cases of a disease 
that occur in a population in a given year, 
accounting for the age differences 
between populations. 

Image Caption:  An exophytic invasive cervical cancer of 
the cervix. 

Men 

Genital infection with low-risk 
types of HPV is associated with 
genital warts in men. 

Infection with high-risk types 
of HPV is associated with 
a proportion of preinvasive 
squamous lesions of the penis 
(penile intraepithelial neoplasia 
or PIN) and with penile cancer, 
as well as with preinvasive 
squamous lesions of the anus 
(anal intraepithelial neoplasia or 
AIN) and with anal cancer.
 
Invasive penile cancer is quite 
uncommon, especially in 
circumcised men. In 2002, the 
age-adjusted incidence rate 
for penile cancer in the U.S. 
was 0.8 per 100,000 men 
(985 new cases).
 
The age-adjusted incidence 
rate for anal cancer was 1.2 per 
100,000 men (1,453 new cases). 
However, the risk of anal 
cancer for MSM is significantly 
higher.34, 35 Because of the 
increased incidence of anal 
cancer in MSM, especially 
HIV-infected MSM, some 
specialists recommend screening 
for AIN by cytology in this 
population. However, there 
are limited data on the natural 
history of AIN, the reliability of 
screening methods, the safety 
and response to treatments, and 
the programmatic considerations 
that would support this screening 
approach. Until more data are 
generated on screening for AIN, 
this screening approach is not 
recommended.36 

Image caption:  Multiple condylomata acuminate on penis. 
Included with permission from the Cincinnati 
STD/HIV Prevention Training Center.

Children
 
Very rarely, genital HPV 
infections can be transmitted 
from mother to baby during 
delivery.37 Perinatally transmitted 
infections with low-risk HPV 
types can result in respiratory 
tract warts in children, a 
condition known as recurrent 
respiratory papillomatosis (RRP). 
RRP is very rare. Estimates of 
the incidence rate for RRP are 
imprecise but range from 0.4 
to 1.1 cases per 100,000 live 
births to women with a history of 
genital warts.38 

It is unclear whether cesarean 
delivery prevents RRP in infants 
and children; thus, cesarean 
delivery should not be performed 
solely to prevent HPV infection in 
the newborn. Cesarean delivery 
may be indicated for women 
with genital warts if the pelvic 
outlet is obstructed or if vaginal 
delivery would result in excessive 
bleeding. 

Prevention 
of Genital 
HPV Infection
 
Prevention of genital HPV 
infection is important in reducing 
the prevalence of genital warts, 
abnormal Pap tests, and cancer.
 
HPV Vaccines
 
Quadrivalent HPV Vaccine 

 A new quadrivalent vaccine, 
Gardasil, protects against 
four HPV types (6, 11, 16, 18), 
which are responsible for 70% 
of cervical cancers and 90% of 
genital warts. 

 This prophylactic vaccine is 
made from non-infectious 
HPV-like particles (or viruslike 
particles, VLP); it does not 
contain thimerosal or mercury.
 
 The vaccine is administered 
through a series of three intramuscular 
injections over a 
six-month period (at 0, 2, and 
6 months).
 
 On June 8, 2006, this vaccine 
was licensed by the Food and 
Drug Administration (FDA), 
becoming the first licensed 
vaccine developed to prevent 
cervical cancer and other 
diseases in females caused by 
genital HPV infection. 

 On June 29, 2006, the 
Advisory Committee on 
Immunization Practices (ACIP) 
voted to recommend use of 
the quadrivalent vaccine in 
females, ages 9 to 26 years 
of age.
 
ACIP Recommendations 
for HPV Vaccine
 
The vaccine should be 
administered to 11- to 
12-year-old girls and can be 
administered to girls as young as 
9 years of age. The vaccine also 
is recommended for 13- 
to 26-year-old females who have 
not yet received or completed 
the vaccine series. 

 Ideally, the vaccine should 
be administered before onset 
of sexual activity. However, 
females who are sexually 
active also may benefit from 
vaccination. Females who 
already have been infected with 
one or more HPV type would 
only get protection from the 
vaccine type(s) they have 
not acquired. 

 For more information about 
the ACIP recommendations, 
including indications and 
contraindications for use, see 
MMWR 56(RR02);1-24, or 
www.cdc.gov/mmwr/preview/ 
mmwrhtml/rr5602a1.htm

Vaccine Safety, Efficacy, 
and Duration of Protection 

 In studies of over 11,000 
females (9 to 26 years of age), 
the vaccine has been found 
to be safe and to cause no 
serious side effects. Adverse 
events were mainly mild 
injection site pain.
 
 Clinical trials have 
demonstrated 100% efficacy in 
preventing cervical precancers 
caused by the targeted HPV 
types and nearly 100% efficacy 
in preventing vulvar and vaginal 
precancers and genital warts 
caused by the targeted HPV 
types among women ages 16 to 
26 years, who were naive to the 
specific HPV vaccine types.39
 
 Data do not indicate that the 
vaccine has any therapeutic 
effect on HPV infection or HPVassociated 
disease, including 
existing Pap test abnormalities 
or genital warts.
 
 While it is possible that 
vaccination of males with the 
quadrivalent vaccine may offer 
direct health benefits to males 
and indirect health benefits to 
females, there are currently 
no efficacy data available to 
support use of HPV vaccine 
in males. Efficacy studies in 
males are ongoing. 

 The duration of vaccine 
protection is unclear.40 Current 
studies (with five-year followup) 
indicate that the vaccine is 
effective for at least five years. 
There is no evidence of waning 
immunity during that time period.
 
HPV Vaccine Cost and Coverage 

 The private-sector list price of 
the vaccine is $119.75 per dose 
(about $360 for the full series).
 
 The federal Vaccines for 
Children (VFC) Program will 
provide free vaccines to 
children and adolescents 
under 19 years of age who are 
uninsured, Medicaid-eligible, 
American Indian, or Alaska 
Native. The VFC Program 
also allows children and 
adolescents to receive VFC 
vaccines through Federally 
Qualified Health Centers or 
Rural Health Centers, if their 
private health insurance does 
not cover the vaccine. 

 Some states also provide 
free or low-cost vaccines 
at public health department 
clinics to people without 
health insurance coverage for 
vaccines. 

 While some insurance 
companies may cover 
the vaccine and cost of 
administration, others may not. 
Most large group insurance 
plans usually cover the cost 
of recommended vaccines. 
However, there is often a short 
lag-time after a vaccine is 
recommended and before 
it is available and covered by 
health plans. 

Although this vaccine offers 
a promising new approach 
to the prevention of HPV and 
associated conditions, this 
vaccine will not replace other 
prevention strategies, such as 
cervical cancer screening or 
protective sexual behaviors, 
because the vaccine will 
not protect against all types 
of genital HPV infection.41 
Cervical cancer screening 
recommendations have not 
changed for females who receive 
the HPV vaccine.
 
Vaccine providers should notify 
vaccinated females that:
 
 They will need regular 
cervical cancer screening as 
the vaccine will not provide 
protection against all types of 
HPV that cause cervical cancer.
 
 They should practice protective 
sexual behaviors (e.g., 
abstinence, monogamy, limiting 
their number of sex partners, 
and using condoms), as the 
vaccine will not prevent all 
cases of genital wartsnor will 
it prevent other STIs.
 
 They may not receive the full 
benefits of the vaccine if they 
receive the vaccine after they 
have become sexually active 
(and may have acquired a 
vaccine HPV type) or if they 
do not complete the full 
vaccine series. 

Counseling messages for 
prospective vaccine recipients 
are provided in an insert at the 
end of this booklet.
 
Other Vaccines in 
Development
 
 A bivalent HPV vaccine was 
submitted to FDA in March 
2007 and may be licensed in 
the next year. This vaccine 
would protect against the two 
types of HPV (16, 18) that 
cause 70% of cervical cancers.
 
 Therapeutic HPV vaccines 
vaccines that prevent 
development of pre-cancerous 
cells in women already infected 
with HPVare not as far along 
in clinical trials.
 
For updates on HPV 
vaccines, please visit:
 
Centers for Disease Control 
and Prevention (CDC) Division of 
STD Preventions HPV website, 
www.cdc.gov/std/hpv 
CDCs National Immunization 
Program website, 
www.cdc.gov/nip
 
ACIPs website, 
www.cdc.gov/nip/ACIP
 
VFC website, 
www.cdc.gov/nip/vfc 

Other Strategies to 
Prevent HPV Infection

Other strategies to prevent 
HPV transmission may include 
(a) reducing the duration of 
infectiousness, (b) decreasing 
the efficiency (likelihood) of 
transmission, and (c) reducing 
the number of sex partners.
 
(a) Reduce the Duration of 
Infectiousness
 
The most common approach to 
reducing infectiousness of an STI 
is treatment. However, there is 
no effective systemic treatment 
for genital HPV, and treatment is 
not recommended for subclinical 
genital HPV infection (diagnosed 
by colposcopy, biopsy, or acetic 
acid application or detected by 
laboratory tests) in the absence 
of squamous intraepithelial 
lesions (SIL).36 There is minimal 
evidence that treatment of HPVassociated 
lesions can prevent 
HPV transmission.
 
 Treatment for genital HPV may 
be applied to lesions, such 
as genital warts (see Genital 
Warts section, page 23), or 
cervical cancer precursors 
(using treatments, such as 
cryotherapy, electrocautery, 
or surgical excision).42
 
 Some evidence suggests that 
treatment of genital warts 
reduces the amount of HPV 
DNA that can be found in the 
tissue. However, it is unknown 
whether treatment reduces 
infectivity of partners.41, 43
 
 It is unclear what proportion 
of HPV-infected persons 
who spontaneously become 
HPV DNA negative truly clear 
HPV, and in what proportion 
of such individuals HPV 
simply becomes dormant or 
undetectable.
 
(b) Decrease the Efficiency 
of Transmission 

The most common approach 
to decreasing the efficiency 
of transmission of an STI is 
to use physical barriers, 
such as condoms.
 
As reported in CDCs Sexually 
Transmitted Diseases (STD) 
Treatment Guidelines, 2006:36
 
 Condom use might reduce 
the risk for HPV-associated 
diseases (e.g., genital warts and 
cervical cancer44) and mitigate 
the adverse consequences of 
infection with HPV. The use of 
condoms has been associated 
with higher rates of regression 
of CIN and clearance of HPV 
infection in women45 and with 
regression of HPV-associated 
penile lesions in men.46
 
 A limited number of 
prospective studies have 
demonstrated a protective 
effect of condoms on the 
acquisition of genital HPV. 
One recent prospective study 
among newly sexually active 
college women demonstrated 
that consistent condom use 
was associated with a 70% 
reduction in risk for HPV 
transmission.47

 However, HPV infection can 
occur in areas that are not 
covered or protected by a 
condom (e.g., scrotum, vulva, 
or perianus).
 
(c) Reduce the Number of 
Sex Partners
 
 The surest way to prevent HPV 
infection is to abstain from any 
genital contact, including nonpenetrative 
intimate contact of 
the genital area.13
 
 For those who choose to be 
sexually active, long-term 
mutual monogamy with a 
single uninfected partner is 
likely to be the next most 
effective approach to prevent 
infection.48 However, it is 
usually impossible to determine 
whether a partner who was 
sexually active in the past is 
currently infected with HPV, 
as most infected people 
are asymptomatic and have 
never had evidence of HPV related 
conditions, such as 
genital warts or Pap test 
abnormalities.2
 
 For those choosing to be 
sexually active, but who are 
not in long-term mutually 
monogamous relationships, 
reducing the number of sex 
partners is another effective 
strategy to avoid acquisition 
of genital HPV infection. 
Choosing a partner who is 
less likely to be HPV-infected 
(e.g., a partner with no or 
few previous sex partners) 
may help reduce the risk of 
acquiring genital HPV.13 

Detection of 
Genital HPV 
Infection
 
HPV DNA Test
 
Molecular tests can be used to 
detect HPV DNA. The only such 
test that is currently approved 
by the FDA is Digenes Hybrid 
Capture II HPV Test, a solution 
hybridization method to test for 
high-risk HPV DNA. Samples 
that can be tested with this 
technology include exfoliated 
cervical cells collected with a 
specially designed brush and 
placed into a liquid medium 
or in residual fluid left over 
from liquid-based cytology 
specimens. This HPV DNA test 
is designed to detect high-risk 
types of HPV (types 16, 18, 31, 
33, 35, 39, 45, 51, 52, 56, 58, 
59, and 68). The HPV DNA test 
detects whether one or more 
types of HPV are present; it does 
not identify individual HPV types.
 
The FDA has approved this 
high-risk HPV DNA assay for 
use in some women in the 
context of cervical cancer 
HPV Infection 
screening (see FDA-Approved 
Indications for High-Risk HPV 
DNA section, page 19). The 
principal utility of the test is in 
identifying women with high-risk 
HPV who are at risk for having 
or developing pre-cancerous or 
cancerous changes (CIN 2, 3 
lesion) in the 36 months following 
initial testing.
 
Another test is available to detect 
low-risk types of HPV, but this 
test is not FDA-approved and 
there are no clinical indications 
for this test.1, 28, 29, 49 

Direct-to-consumer advertising 
may prompt demand for the HPV 
test. However, while patients 
may request an HPV test, use 
of this test should be limited 
to the uses recommended by 
professional organizations (see 
FDA-Approved Indications for 
High-Risk HPV DNA Testing, 
page 19). 

There is currently no FDAapproved 
HPV DNA test for 
males, nor is HPV testing of 
males recommended. There is no 
clinical utility in testing men for 
HPV; infection does not indicate 
increased risk of disease for the 
man or his partner. While HPV is 
common in men, HPV-associated 
cancers are rare.
 
HPV DNA testing should not 
be used:
 
 for men;
 
 to check the HPV status of 
patients with genital warts or 
other STIs;
 
 to check the HPV status of 
partners of patients with genital 
warts or other STIs;
 
 to check the HPV status of 
partners of women with cervical 
cancer abnormalities; or
 
 to check the HPV status of 
pregnant women.
 
Other HPV Tests
 
There are no routine methods 
for culturing HPV. Serology tests 
are available for HPV, but these 
tests are used only in research 
settings. Many persons with 
detectable HPV DNA do not have 
antibodies, so these tests are 
not a good method to indicate 
infection with HPV.50 

Although primary prevention 
and detection are generally 
clinical objectives for STI care, 
HPV infection offers unique 
challenges. Infection is both 
very common in sexually active 
individuals, and it is generally 
asymptomatic. The ubiquitous 
nature of the virus, coupled 
with a relative rarity of clinical 
signs and symptoms, suggests 
focusing on the detection, 
prevention, and treatment of 
the potential consequences of 
HPV infection.

Section II: Prevention of Cervical Cancer
 
Cervical cancer once claimed 
the lives of more American 
women than any other type 
of cancer. But over the last 
40 years, widespread cervical 
cancer screening using 
the Pap test and treatment 
of pre-cancerous cervical 
abnormalities have resulted 
in a marked reduction in the 
incidence of and mortality due 
to cervical cancer in the U.S.3 
The American Cancer Society 
(ACS) estimates that in 2006, 
approximately 9,710 cases of 
invasive cervical cancer will be 
diagnosed, and 3,700 women 
will die from this disease in 
the U.S. 

The advent of an HPV vaccine 
(see HPV Vaccines, page 9) now 
offers an additional, promising 
method of preventing up to 
70% of cervical cancer cases 
through primary prevention. 
However, regular cervical cancer 
screening will still be necessary 
for vaccinated women because: 

1. The vaccine will NOT provide 
protection against all types 
of HPV that cause cervical 
cancer.
 
2. Women may not receive the 
full benefits of the vaccine 
if they do not complete the 
vaccine series.
 
3. Women may not receive the 
full benefits of the vaccine if 
they receive the vaccine after 
they have already acquired a 
vaccine HPV type. 

Key Public Health 
Message
 
Approximately half of all cervical 
cancers occur in women who 
have never been screened.31 
Therefore, screening is 
particularly important in women 
who have never or rarely been 
screened.
 
The following section focuses 
on secondary prevention 
of cervical cancer through 
cytology and HPV DNA testing. 
For an overview of primary 
prevention through vaccines, 
please see the HPV Prevention 
section on page 9.
 
Image caption: An exophytic invasive cervical cancer of 
the cervix is present. When cancers are not 
necrotic they can sometimes be mistaken for a 
large cervical condyloma.
 

Table 3: Cervical Cancer Screening Guidelines
 
American Cancer Society1 
www.cancer.org 
(ACS, Nov 2002) 

When to start Approximately 3 years after 
onset of vaginal intercourse, 
but no later than age 21
 
Intervals 
 Conventional Pap test Annually; every 2-3 years for 
women =30 with 3 negative 
cytology tests* 

 If liquid-based cytology used** Every 2 years; every 2-3 years 
for women =30 with 3 negative 
cytology tests*  

 If HPV testing used** Every 3 years if HPV negative, 
cytology negative 
 
When to stop Women >70 years with >3 
recent, consecutive negative 
tests & no abnormal tests in 
prior 10 years* 

Post total hysterectomy Discontinue if for benign reasons 
& no prior history of high-grade 
CIN*
 
* Some exceptions apply (e.g., women who are immunocompromised, have a history 
of prenatal exposure to DES). See guidelines for details.
 
** See Table 2 at www.cdc.gov/std/hpv/screening (entitled, Recommendations for 
Liquid-Based Cytology and HPV Testing) for recommended use.

U.S. Preventive 
Services Task Force2 
www.ahrq.gov/clinic/uspstfix.htm 
(USPSTF, Jan 2003) 
 
Within 3 years of onset of 
sexual activity or age 21, 
whichever comes first

 At least every 3 years 

 Insufficient evidence
 
 Insufficient evidence 

Women >65 years with negative 
tests, who are not otherwise at 
high risk for cervical cancer

Discontinue if for benign reasons  
 
American College 
of Obstetricians and 
Gynecologists3 
www.acog.org 
(ACOG, Aug 2003)

Approximately 3 years after 
onset of sexual intercourse, 
but no later than age 21

 Annually; every 2-3 years for 
women =30 with 3 negative 
cytology tests*  

 Annually; every 2-3 years for 
women =30 with 3 negative 
cytology tests* 

 Every 3 years if HPV negative, 
cytology negative 

Inconclusive evidence to 
establish upper age limit 

Discontinue if for benign reasons 
& no prior history of high-grade 
CIN* 

1. Saslow D, et al. American Cancer Society Guideline for the Early Detection of 
Cervical Neoplasia and Cancer. CA Cancer J Clin 2002; 52: 342-362. Available at 
http://caonline.amcancersoc.org/cgi/content/full/52/6/342 

2. USPSTF. Screening for Cervical Cancer. Jan 2003. Available at: http://www.ahcpr. 
gov/clinic/uspstf/uspscerv.htm 

3. ACOG. Cervical Cytology Screening. ACOG Practice Bulletin No. 45. ACOG 
2003;102: 417-427. See also: http://www.acog.org/from_home/publications/press_ 
releases/nr07-31-03-1.cfm 

Screening 
with Cervical 
Cytology 

The purpose of cervical cancer 
screening is to identify cervical 
cancer precursors that can be 
treated before they progress to 
cervical cancer.
 
There are three major 
professional organizations that 
issue cervical cancer screening 
guidelines: the U.S. Preventive 
Services Task Force (USPSTF); 
the American College of 
Obstetricians and Gynecologists 
(ACOG); and the ACS. Their 
screening recommendations are 
summarized in Table 3 on page 16.
 
Both conventional Pap tests 
(smear and slide) and a 
new liquid-based cytology 
(a method in which cervical 
cells are collected into a liquid 
medium) can be used to screen 
for cervical cancer. 

 The sensitivity of the 
conventional Pap test ranges 
from 30% to 87%, and the 
specificity ranges from 86% to 
100%53
 
 The sensitivity of liquid-based 
cytology ranges from 61% to 
95%, and the specificity ranges 
from 78% to 82%52, 53 

 The U.S. Preventive Services Task Force is 
an independent panel of experts in primary 
care and prevention that systematically 
reviews the evidence of effectiveness and 
develops recommendations for clinical 
preventive services.

Image Captions: 

Top: There is a cluster of cells with enlarged, 
hyperchromatic nuclei present. Several 
binucleated cells are present in this cluster. 
However, very few atypical cells were present on 
slide and although the cells are suggestive of SIL, 
they are not diagnostic of SIL.
 
Bottom: This cervix has a well-circumscribed 
area of acetowhitening that appears low-grade. 
However, cervical biopsy was diagnosed as 
CIN 2,3. 
 
HPV DNA 
Testing for 
High-Risk Types
 
A high-risk HPV DNA test is 
commercially available and 
approved for use in women in 
the setting of cervical cancer 
screening and management.

FDA-Approved 
Indications for High-Risk 
HPV DNA Testing
 
Testing is approved for: 

 Use in the management of 
women with ASC-US cervical 
cytology results. This test 
can be used to help determine 
which women (of any age) 
with ASC-US cervical cytology 
results should be referred for 
colposcopy and which can be 
followed up with cytological 
screening in 12 months.54
 
 Routine adjunctive screening 
with cervical cytology 
screening for women ages 
0 and older (e.g., use in 
conjunction with a Pap 
test for primary screening). 
This test is not approved for 
use with cervical cytology 
screening in women younger 
than age 30 because HPV 
infection is highly prevalent 
and usually transient in women 
at younger ages, while the 
prevalence of cervical cancer 
is relatively low, compared to 
older women. 
 
Use of HPV DNA 
Testing in Managing 
Women with ASC-US
 
Borderline cytologic abnormalities 
referred to as ASC-US are quite 
common in the U.S. Approximately 
4% to 5% of all cervical cytology 
results are reported as ASC-US.
 
Use of the HPV DNA test in the 
management of women with 
ASC-US Pap test results is 
recommended as an option by the 
American Society for Colposcopy 
and Cervical Pathology (ASCCP, 
www.asccp.org/index.html), ACS, 
and ACOG. The USPSTF found 
the evidence insufficient in its last 
review (2003) to recommend for 
or against the use of HPV DNA 
testing in this setting.56 

Management of Women 
with ASC-US Using 
HPV DNA Testing 

According to ACOG, ACS, and 
ASCCP guidelines:
 
 If the woman is found to 
be HPV DNA positive, refer 
to colposcopy.
 
 If the woman is found to be 
HPV DNA negative, repeat 
cytology in 12 months. 

Management of Women with Atypical Squamous 
Cells of Undetermined Significance (ASC-US) 

HPV DNA Testing 
Preferred if liquid-based 
cytology or co-collection 
available 

HPV Positive 
(for high-risk types) 

Colposcopy

No CIN/Cancer 
Cytology @ 6 & 12 mos 
OR 
HPV DNA testing @ 12 mos

= ASC or HPV (+)
Repeat Colposcopy

Negative 
Routine Screening  

CIN/Cancer 
Manage per 
ASCCP Guideline 

HPV Negative 
(for high-risk types) 
Repeat Cytology @ 12 months 
  
Reprinted from The Journal of Lower Genital Tract Disease Vol. 6 Issue 2 with the permission 
of the ASCCP American Society for Colposcopy and Cervical Pathology 2002. 

Management of Women Ages 30 and Older, 
Based on Cytology and HPV DNA Testing Results 

Cytology negative 
HPV negative
Routine Screening at 3 years 

Cytology negative 
HPV positive 
Repeat both tests at 6 - 12 months

Both negative 
Routine screening at 3 years 

Cytology ASC-US 
HPV negative 
Rescreen with cytology and HPV at 12 months
 
Cytology >ASC-US
HPV negative 
Colposcopy 

Any cytology result 
HPV positive 
Colposcopy

Cytology ASC-US 
HPV negative
Repeat Cytology at 12 months 

Cytology ASC-US 
HPV Positive
Colposcopy 
 

Cytology > ASC-US 
any HPV result 
Colposcopy

Reprinted from Interim guidance for the use of human papillomavirus DNA testing as an 
adjunct to cervical cytology for screening. Wright TC, Schiffman M, Solomon D, et al. 
Obstetrics and Gynecology 2004; 103(2): 304-309 fi g. 1. 
These algorithms can also be found as tear-outs at the end of this booklet.

High-risk HPV DNA testing 
may be a practical approach to 
managing women with ASC-US 
whenever liquid-based cytology 
is used for screening or when 
co-collection of a sample 
for HPV DNA testing can be 
performed. This is because 
HPV DNA testing may be more 
convenient for patients than their 
returning for a repeat cytology; 
approximately half of women 
with ASC-US will be high-risk 
HPV DNA negative and will not 
require colposcopy.57 HPV DNA 
testing in this setting has been 
shown to be more cost-effective 
than the other management 
strategies.54, 58 

Use of HPV DNA 
Testing for Routine 
Adjunctive Screening 
with a Pap Test for 
Women Age 30 and 
Older 

The combination of molecular 
testing for high-risk types of 
HPV together with a Pap test 
is considered by the ACS and 
ACOG to be an acceptable 
approach to cervical cancer 
screening of women age 30 
and older.54, 59, 60 However, the 
USPSTF found the evidence 
insufficient to recommend for 
or against the routine use of 
HPV DNA testing as a primary 
screening test for cervical 
cancer.58 

Patient Followup Based 
on Cytology and HPV 
DNA Testing 

According to ACS and ACOG 
guidelines:
 
 Women with negative results 
on both tests should not be 
re-screened for at least three 
years.
 
 Women who are HPV DNA 
positive, but cytology negative, 
should not be referred for 
colposcopy. Instead, they 
should be re-tested with both 
tests in 6 to 12 months.
 
Re-screening for women found 
to be both cytology negative and 
high-risk HPV DNA negative can 
be done at three years.54 This is 
because women with negative 
results by both cytology and 
HPV DNA testing have a very low 
risk of having a CIN 3 lesion or 
of developing a CIN 3 over the 
next three years.54, 61, 62, 63 The 
extended testing interval of three 
years in women who are both 
cytology negative and HPV DNA 
negative is a benefit of HPV DNA 
testing.
 
Please see the 2001 Consensus 
Guidelines for Managing Women 
with Cytological Abnormalities 
and Interim Guidance for Use 
of HPV DNA Testing as an 
Adjunct to Cervical Cytology 
for Screening for more 
information.54, 55 

HPV DNA testing should 
not be used: 

 in women <30 years of age 
with any Pap test result other 
than ASC-US; 

 as an adjunct to Pap for 
primary screening of women 
<30 years of age; 

 as an adjunct to Pap for 
women who are immuno 
compromised for any reason, 
including infection with HIV; 
and 

 as an adjunct to Pap for 
women who have had total 
hysterectomy for benign 
gynecologic disease.
 
Other Uses of HPV DNA 
Testing for High-Risk Types 

One professional organization 
also recommends use of the 
HPV DNA test for followup 
of cervical abnormalities 
(www.asccp.org); however there 
is no FDA-approved indication 
for this use. 

Performance of HPV DNA 
Testing Combined with 
Cytology for Women Over 
30 Years of Age 

In international cross-sectional 
studies that examined both 
cytology and the HPV DNA test 
result:54 

 The sensitivity of a single Pap 
test for identifying CIN 2, 3 or 
cancer ranged from 33% to 
94% (adding the HPV DNA 
test to conventional cytology 
increased the sensitivity to 
87% to 100%).
 
 The specificity of a single 
Pap test ranged from 87% to 
98%. Adding the HPV DNA 
test to conventional cytology 
decreased the specificity to 
69% to 95%.
 
Published studies have found 
that colposcopy is more sensitive 
than HPV DNA testing or repeat 
cytology for detection of cervical 
cancer precursor lesions; HPV 
DNA testing is more sensitive 
than repeat cytology.57, 64 

Remember:
 
 Women who are HPV DNA 
negative and cytology negative 
are at very low risk for having 
CIN 2, 3 or for developing it 
within the next three years and 
can be re-screened at three 
years. 

 The risk that women who 
are HPV DNA positive, but 
cytology negative, will have 
CIN 2, 3 or cancer is very low. 
Therefore, colposcopy should 
not be performed routinely in 
this circumstance. HPV DNA 
testing along with cervical 
cytology should be repeated 
at 6 to 12 months. If the 
woman is persistently high-risk 
HPV DNA positive, then she 
should receive a colposcopic 
examination. 

The use of the HPV DNA test 
may introduce new psychological 
and interpersonal components 
to cervical cancer screening 
and management. Women may 
experience anxiety, distress, fear, 
anger, and guilt in response to 
an HPV diagnosis.65 Providers 
should provide patients 
information and counseling when 
administering the test and when 
delivering HPV DNA test results.
 
Counseling messages for women 
receiving the HPV DNA test with 
Pap for cervical cancer screening 
are provided in an insert at the 
end of this booklet.
 
Counseling Women 
Infected with 
Genital HPV 

According to a national survey 
conducted in 2005, less than 
half of American women had 
heard of HPV, and only 23% of 
women were able to identify HPV 
as the primary cause of cervical 
cancer.66 While HPV awareness 
levels seem to be increasing 
among women (58%), it is 
unclear whether knowledge of its 
association with cervical cancer 
is increasing.67 

Qualitative surveys indicate that 
women want more information 
about HPV, specifically with 
respect to transmission, 
prevention, progression, and 
treatment, as well as risk of 
cancer.3
 
The provision of patient 
information and counseling 
must be considered both when 
administering the HPV DNA 
test and when delivering test 
results. The manner in which this 
information is communicated 
to patients can influence the 
psychological effect of this 
diagnosis, as well as a 
womans likelihood of following 
up with necessary testing or 
treatment.68, 69, 70
 
Counseling messages for 
patients with a high-risk HPV 
DNA test result are included in an 
insert at the end of this booklet.
 
Section III: Genital Warts
 
Diagnosis
 
 Diagnosis of genital warts is 
made by visual inspection.
 
 A genital warts diagnosis 
may be confirmed by biopsy, 
although biopsy is needed only 
in certain circumstances. 

 The use of HPV tests is not 
indicated for the routine 
diagnosis or management of 
visible genital warts. 

Treatment
 
 If left untreated, genital warts 
may resolve on their own, 
remain unchanged, or increase 
in size or number.
 
 The effect of treatment on 
future transmission of HPV 
infection is unclear.
 
 The primary goal of treating 
visible genital warts is removal 
for cosmetic reasons.
 
 In most patients, treatment 
can remove warts. However, 
recurrences are frequent.
 
 Some patients may forego 
treatment as genital warts may 
resolve on their own. 

Treatment Regimens
 
 A number of treatment options 
are available for visible genital 
warts. There is no definitive 
evidence to suggest that any 
one treatment is superior 
to others. Factors that may 
influence the selection of 
treatment include patient 
preference; available resources; 
provider experience; the size, 
number, anatomic site, and 
morphology of wart(s); and the 
cost, convenience, and adverse 
effects of treatment.
 
 Providers should be 
knowledgeable about and have 
available at least one patientapplied 
and one provideradministered 
treatment. 

Table 4: Recommended Treatment Regimens
 
Patient-Applied Treatments 
 Podofilox* 0.5% solution 
or gel 
 Imiquimod* 5% cream 

Provider-Applied Treatments 
 Cryotherapy 
 Podophyllin resin* 
 Trichloroacetic Acid (TCA) 
or Bichloroacetic Acid (BCA) 
80%90% 
 Surgical Removalby 
tangential scissor excision, 
tangential shave excision, 
curettage, or electrosurgery.
 
Note: If possible, the health care provider should apply initial 
treatment to demonstrate the proper application technique and 
identify which warts should be treated. Follow-up visits may be 
useful several weeks into therapy to determine appropriateness of 
medication use and patient response to treatment.
 
* These treatments should not be used during pregnancy, as their safety during 
pregnancy has not been established. 

Patients may prefer the privacy 
and convenience of patientapplied 
modalities.
 
 Many patients require a course 
of therapy rather than a single 
treatment.
 
 There is no evidence that the 
use of more than one therapy 
at a time will improve efficacy.
 
 The response to treatment and 
treatment side effects should 
be evaluated throughout the 
course of therapy. Treatment 
modality should be changed 
if a patient has not improved 
substantially.
 
 The use of locally developed 
and monitored treatment 
algorithms has been associated 
with improved clinical 
outcomes and is encouraged.
 
Please refer to CDCs Sexually 
Transmitted Diseases 
Treatment Guidelines, 2006 36 
(www.cdc.gov/STD/treatment) 
for more information about these 
treatments, including safety 
indications, directions for use, 
benefits, adverse effects, and 
possible complications.
 
Counseling Patients 
with Genital Warts
 
Information and counseling are 
important aspects of managing 
patients with genital warts. 
Counseling is most effective if 
provided in a non-judgmental 
manner appropriate to the 
patients culture, language, sex, 
sexual orientation, age, and 
developmental level.
 
Counseling messages for 
patients with genital warts are 
included in an insert at the end 
of this booklet.
 
Special 
Considerations 
for Women
 
 Neither the presence of genital 
warts nor their treatment is 
associated with the development 
of cervical cancer in women. 
Therefore, the presence of 
genital warts is not an indication 
for cervical colposcopy or a 
change in the frequency of Pap 
tests for women.
 
 The presence of genital warts 
alone is not an indication for 
cesarean delivery in expectant 
women. Cesarean delivery 
may be indicated for women 
with genital warts if the pelvic 
outlet is obstructed or if 
vaginal delivery would result in 
excessive bleeding.
 
 Pregnant women with genital 
warts should be counseled 
about the low risk of warts on 
the larynx (recurrent respiratory 
papillomatosis) in their infants 
or children. There are no 
controlled studies suggesting 
that cesarean delivery prevents 
this condition. 

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