Seroprevalence of Human Papillomavirus Type 16 in Children

Seroprevalence of mucosal and cutaneous human papillomavirus (HPV) types among children and adolescents in the general population in Germany

Background

In Germany, HPV vaccination of adolescent girls was introduced in 2007. Nationally representative data on the distribution of vaccine-relevant HPV types in the pre-vaccination era are, however, only available for the adult population. To obtain data in children and adolescents, we assessed the prevalence and determinants of serological response to 16 different HPV types in a representative sample of 12,257 boys and girls aged 1–17 years living in Germany in 2003–2005.

Methods

Serum samples were tested for antibodies to nine mucosal and seven cutaneous HPV types. The samples had been collected during the nationally representative German Health Interview and Examination Survey for Children and Adolescents in 2003–2006. We calculated age- and gender-specific HPV seroprevalence. We used multivariable regression models to identify associations between demographic and behavioral characteristics and HPV seropositivity.

Results

We found low but non-zero seroprevalence for the majority of tested HPV types among children and adolescents in Germany. The overall seroprevalence of HPV-16 was 2.6%, with slightly higher values in adolescents. Seroprevalence of all mucosal types but HPV-6 ranged from 0.6% for HPV-33, to 6.4% for HPV-31 and did not differ by gender. We found high overall seroprevalence for HPV-6 with 24.8%. Cutaneous HPV type seroprevalence ranged from 4.0% for HPV-38 to 31.7% for HPV-1. In the majority of cutaneous types, seroprevalence did not differ between boys and girls, but increased sharply with age, (e.g., HPV-1 from 1.5% in 1–3-years-old to 45.1% in 10–11-years-old). Associations between behavioral factors and type-specific HPV prevalence were determined to be heterogeneous.

Conclusions

We report the first nationally representative data of naturally acquired HPV antibody reactivity in the pre-HPV-vaccination era among children and adolescents living in Germany. These data can be used as baseline estimates for evaluating the impact of the current HPV vaccination strategy targeting 9–14-years-old boys and girls.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07028-8.

High seroprevalence of multiple high-risk human papillomavirus types among the general population of Bonaire, St. Eustatius and Saba, Caribbean Netherlands

BACKGROUND

Incidence and mortality of human papillomavirus (HPV)-related cancers differs geographically, with high rates in Caribbean countries. Seroepidemiological data provide information on lifetime cumulative HPV exposure and contributing risk factors, but has not been available yet for Caribbean Netherlands (CN), comprising the islands Bonaire, St. Eustatius and Saba. Therefore, a cross-sectional population-based serosurveillance study was performed in this (recently girls-only HPV-vaccinated) population in 2017.

METHODS

Blood samples from participants (n = 1,823, 0-90 years) were tested for seven high-risk (hr)-HPV-specific IgG-antibodies using a VLP-based multiplex-immunoassay. Risk factors for HPV-seropositivity were analysed among persons unvaccinated aged ≥ 15 years who ever had sex (n = 1,080).

RESULTS

Among unvaccinated individuals aged ≥ 15 years, overall seropositivity was high (34%), with over half of them being seropositive for ≥ 2 hr-HPV types, and HPV16 and 52 being most prevalent (13%). Seroprevalence was substantial higher in unvaccinated women (51%) than men (18%), predominantly peaking in women aged 20-59 years, and was highest on St. Eustatius (38%). Besides age and sex, sexual risk factors were associated with HPV-seropositivity.

CONCLUSIONS

In accordance with the Caribbean region, seroprevalence of multiple hr-HPV types was high in CN. These data corroborate the decision regarding introduction of a sex-neutral HPV-vaccination program and the relevance for considering a population-based cervical cancer screening program.

Quality Improvement Initiative to Improve Human Papillomavirus Vaccine Initiation at 9 Years of Age

OBJECTIVE

Adolescent human papillomavirus (HPV) vaccine rates remain low. Early vaccination may improve the efficacy of the vaccine and immunization rates; however, clinicians have not routinely made a strong recommendation for younger adolescents. This study assessed the feasibility of routine vaccination at 9 years of age.

METHODS

Three sequential quality improvement (QI) interventions were implemented to shift the initiation of the HPV vaccine to 9 years of age in a primary care network in low-income neighborhoods in Columbus, Ohio. The first intervention changed the electronic medical record alert for the HPV vaccine from 11 to 9 years of age and focused on cancer prevention when discussing the vaccine with families. The second intervention was formation of an HPV QI team. The third intervention was a clinic incentive for HPV captured opportunity rates. Immunization rates were monitored using statistical process control charts to compare the HPV immunization rate in a sample of 9- and 10-year-old children with a sample of 11- and 12-year-old children.

RESULTS

The percentage of patients receiving an HPV vaccine before 11 years increased from 4.6% to 35.7% during the 6 months after the QI initiative began and to 60.8% 18 months after the project began. In comparison, the HPV vaccination rate in the sample of 11- and 12-year-olds increased from 78.7% to 82.8% 18 months later.

CONCLUSIONS

This QI project used multiple interventions to increase HPV vaccination at 9 years of age in a large primary care network serving a diverse low-income population.

Antibody response to human papillomavirus vaccination and natural exposure in individuals with Fanconi Anemia

Fanconi anemia (FA) is a rare genetic disorder associated with predisposition to head and neck and gynecological squamous cell cancers. In the general population, these cancers are commonly linked to human papillomavirus (HPV) infection. Antibodies to natural HPV infection and HPV vaccination were evaluated in 63 individuals with FA while considering host immune factors. Approximately 30% of reportedly unvaccinated participants were seropositive (HPV6-38%, HPV11-25%, HPV16-26%, and HPV18-26%). Seropositivity was significantly associated with having had sex regardless of age (p=.007). Most participants showed seropositivity after HPV vaccination (HPV6-100%, HPV11-100%, HPV16-100% and HPV18-92%). Interestingly, titers for all 4 subtypes were significantly lower in the post-hematopoietic stem cell transplant (HSCT) participants compared to those who received the vaccine, but had not undergone HSCT (HPV6-p=.030, HPV11-p=.003, HPV16-p=.018, HPV18-p=<.001). It is unclear if these titers sufficiently protect from new infection since protective serologic cut offs have not yet been defined for the HPV vaccine. Individual immune functions were not associated with HPV seropositivity, however, underlying heterogeneous immune deficiency may explain higher rates of seropositivity in our younger unvaccinated participants (age 4-13 years). To better measure the efficacy of HPV vaccination in those with FA and other immune-compromised or cancer-prone disorders, future well-controlled vaccine studies are required.

Seroprevalence of seven high-risk HPV types in The Netherlands

BACKGROUND

To obtain insight into the age-specific seroprevalence for seven high-risk human papillomavirus (hr-HPV) serotypes (HPV16, 18, 31, 33, 45, 52, and 58) among the general population in the pre-vaccination era in The Netherlands.

METHODS

From a cross-sectional population-based study (ISRCTN 20164309) performed in 2006/2007 6384 sera of men, women and children were tested for seven hr-HPV specific antibodies using a fluorescent bead-based multiplex immunoassay with virus-like particles of the seven HPV serotypes.

RESULTS

An increase in seroprevalence was observed in adolescents, especially for the most prevalent HPV type 16 (up to 11.3%). The increase was most pronounced in women, but was less clear for the other six HPV serotypes. Relatively stable seroprevalences were found in the middle aged cohorts and a slight decrease in the elderly. For the age cohorts >14 years, the seroprevalence among women (25.2%) was higher compared with men (20.3%) (p=0.0002). We found that 10.1% of the population was seropositive for multiple HPV serotypes.

CONCLUSIONS

The HPV vaccination program is targeted at preadolescents as is justified by the results in this study in which a step-up in HPV seroprevalence is observed at ages of sexual debut. Although direct interpretation of seroprevalence data are hampered by cross-reactivity and seroconversion rate, these data are useful as baseline to evaluate long-term population effects of the HPV16/18 vaccination program.

Cross-sectional study on the prevalence of HPV antibodies in the general population of the Czech Republic

Objectives

The assessment of the prevalence of antibodies to human papillomaviruses (HPV) in the healthy population is essential for effective planning of HPV vaccine implementation into the preventive programmes for HPV-associated diseases and for the prospective monitoring of the impact of HPV vaccines in the Czech population.

Methods

The seropositivity for HPV-6, 11, 16, 18, 31 and 33 virus-like particles was determined in sera from 3150 healthy individuals (age range 6–76 years) by means of enzyme-linked immunoassay.

Results

The seroprevalences for HPV-6, 11, 16, 18, 31 and 33 were 23.8%, 15.2%, 14.5%, 9.9%, 16.4% and 9.6% in women and 18.4%, 13.7%, 6.5%, 5.4%, 6.1% and 4.3% in men. For both genders, except for HPV11, these rates were age dependent. The prevalence of antibodies to HPV-16 and/or 18 reached the maximum of 27.0% in women 30–39 years of age and of 14.4% in men 50–59 years of age. The highest proportion of individuals' seropositive for any of the vaccine types HPV-6/11/16/18 was in 30- to 39-year-old women (50.0%) and in ≥60-year-old men (37.6%). Antibodies specific for vaccine HPV types were detected in 18.0% of children 6- to 14-year-old but in 26.4%, those older than 14 years.

Conclusions

The data reveal age-specific differences in the HPV seropositivity rates between healthy women and men and support the implementation of HPV vaccination in the Czech Republic before the age of 13.

Age-specific human papillomavirus antibody and deoxyribonucleic acid prevalence: a global review

PURPOSE

Global data on human papillomavirus (HPV) serological and deoxyribonucleic acid (DNA) prevalence are essential to optimize HPV prophylactic vaccination strategies.

METHODS

We conducted a global review of age-specific HPV antibody and studies with both antibody and DNA prevalence for HPV-16, -18, -6, and -11.

RESULTS

One hundred seventeen studies were included; participants' ages ranged from several hours to >90 years. HPV-16 seroprevalence was generally higher in Africa, Central and South America, and North America, more prevalent among women than among men, and peaked around ages 25-40 years. HPV-18 seroprevalence was generally lower than HPV-16 with a later age peak. Data were limited for HPV-6 and -11, both of which peaked at ages similar to HPV-18. Among 9-26-year-old females, HPV-16 seroprevalence ranged from 0%-31% in North America, 21%-30% in Africa, 0%-23% in Asia/Australia, 0%-33% in Europe, and 13%-43% in Central and South America. HPV-16/-18 DNA prevalence peaked 10-15 years before corresponding HPV-16/-18 antibody prevalence.

CONCLUSIONS

Females within the HPV vaccine-eligible age-group (9-26 years) had a range of dual HPV-16 DNA and serology negativity from 81%-87%, whereas 90%-98% were HPV-16 DNA negative. Serology and DNA data are lacking worldwide for females younger than age 15 years, the prime target group for vaccination.

Next Generation Cancer Protection: The Bivalent HPV Vaccine for Females

Nearly a half a million women throughout the world develop cervical cancer every year Parkin and Bray (“Chapter 2. The burden of HPVrelated cancers,” Vaccine, vol. 24, no. 3, pp. S11–S25, 2006); 80% of these women are in countries without a quality-assured cytology screening program. It is in this setting that Cervarix could reduce the incidence of cervical cancer to about 9.5/100,000 women. New evidence indicates that this might be able to be accomplished with a single dose of Cervarix, a great advantage to public health implementation programs Kreimer et al. (“Proof-of-principle evaluation of the efficacy of fewer than three doses of a bivalent HPV16/18 vaccine, The Journal of the National Cancer Institute, vol. 103, no. 19, pp. 1444–1451, 2011). In countries with screening programs, adenocarcinoma is the most difficult to detect and treat with later-stage presentation and higher mortality Smith et al. (“The rising incidence of adenocarcinoma relative to squamous cell carcinoma of the uterine cervix in the United States—a 24-year population-based study,” Gynecologic Oncology, vol. 78, no. 2, pp. 97–105, 2000) and Gunnell et al. (“A longitudinal Swedish study on screening for squamous cell carcinoma and adenocarcinoma: evidence of effectiveness and overtreatment,” Cancer Epidemiology Biomarkers and Prevention, vol. 16, no. 12, pp. 2641–2648, 2007). With additional cross-protection to HPV 31, 33, and 45 and protection against HPV 16 and 18 lasting at least 9.4 years, Cervarix may reduce adenocarcinomas in screened populations by more than 90%. This paper will detail the evidence about the efficacy, immunogenicity, and safety of Cervarix in the studied populations contrasting public health goals with individual health options.

Factors affecting transmission of mucosal human papillomavirus

Human papillomavirus (HPV) is the most common sexually transmitted infection. The effect of HPV on public health is especially related to the burden of anogenital cancers, most notably cervical cancer. Determinants of exposure to HPV are similar to those for most sexually transmitted infections, but determinants of susceptibility and infectivity are much less well established. Gaps exist in understanding of interactions between HPV, HIV, and other sexually transmitted infections. The roles of mucosal immunology, human microbiota at mucosal surfaces, host genetic factors and hormonal concentrations on HPV susceptibility and infectivity are poorly understood, as are the level of effectiveness of some primary or secondary preventive measures other than HPV vaccination (such as condoms, male circumcision, and combination antiretroviral therapy for HIV). Prospective couples studies, studies focusing on mucosal immunology, and in-vitro raft culture studies mimicking HPV infection might increase understanding of the dynamics of HPV transmission.

Current concepts on human papillomavirus infections in children

Current evidence is strong enough to conclude that human papillomavirus (HPV) can be transmitted both sexually and non-sexually. The debate on HPV infections in children still continues but it is more focused on HPV prevalence than on transmission modes. HPV DNA detection in amniotic fluid, foetal membranes, cord blood and placental trophoblastic cells all suggest HPV infection in utero, i.e. prenatal transmission. Based on recent meta-analysis, vertical transmission occurs in approximately 20% of cases. Most of the mucosal HPV infections in infants are incident, persistent infections in oral and genital mucosa being found in less than 10% and 2% respectively. The mother seems to be the main transmitter of HPV to her newborn, but subsequent HPV infections are acquired horizontally via saliva or other contacts. Bimodal peak prevalence is seen for skin warts, oral papillomas and recurrent respiratory papillomatosis (RRP) in younger and older age groups, suggesting similar epidemiology. Of the clinical HPV diseases, juvenile-onset-RRP and genital condylomata are problematic; the former because of its life-threatening potential and the latter because of possible sexual abuse. HPV6 and 11 are the most common genotypes in both the lesions. Early in life, infections by the high-risk HPV genotypes may also remain persistent for a considerable period, and should be of considerable importance for HPV vaccination strategies.

Current prophylactic HPV vaccines and gynecologic premalignancies

PURPOSE OF REVIEW

Studies of the human papillomavirus (HPV) vaccines, Cervarix and Gardasil provide strong evidence for the recommendation that HPV vaccines may minimize the incidence of cervical cancer over time.

RECENT FINDINGS

Both Cervarix and Gardasil provided more than 90% efficacy in preventing cervical intraepithelial neoplasia grade 2+ (CIN 2+) disease caused by HPV 16 and 18 in women 16-26 years who were seronegative and PCR-negative for HPV 16 and 18 at baseline. Cervarix provides more than 75% efficacy in independent cross-protection against persistent HPV 31 and 45, and 47% efficacy against HPV 33; whereas Gardasil offers 50% efficacy only against persistent HPV 31. A reduction in excisional therapies for CIN 2+ is nearly 70% for Cervarix, and 40% for Gardasil. Cervarix efficacy is documented to 6.4 years; Gardasil's to 5 years. Immunologically, Cervarix induces three to nine-fold higher peak-neutralizing antibody titers to HPV 16/18 than Gardasil, has significantly higher cervicovaginal mucus-neutralizing antibody presence than Gardasil, and significantly higher B memory cell response than Gardasil. Safety reports indicate injection site reactions for both Cervarix and Gardasil. Rare serious adverse events have been reported.

Currently approved prophylactic HPV vaccines

Cervarix and Gardasil are two prophylactic HPV vaccines designed primarily for cervical cancer prevention. Cervarix is effective against HPV-16, -18, -31, -33 and -45, the five most common cancer-causing types, including most causes of adenocarcinoma for which we cannot screen adequately. Gardasil is effective against HPV-16, 18 and 31, three common squamous cell cancer-causing types. In addition, Gardasil is effective against HPV-6 and -11, causes of genital warts and respiratory papillomatosis. The most important determinant of vaccine impact to reduce cervical cancer is its duration of efficacy. To date, Cervarix's efficacy is proven for 6.4 years and Gardasil's for 5 years.

Sexual abuse and sexually transmitted infections in children and adolescents

PURPOSE OF REVIEW

Sexual abuse is unfortunately common in the United States. The presence of a sexually transmitted infection in a child or adolescent should prompt an evaluation to exclude sexual abuse.

RECENT FINDINGS

The present article reviews the demographics of sexual abuse, the prevalence of specific sexually transmitted infections, such as Neisseria gonorrhoeae, Chlamydia trachomatis, HIV, human papillomavirus (HPV) and herpes simplex virus (HSV) and which children and adolescents are at highest risk for contracting such infections. The use of nonculture methods, such as nucleic acid amplification tests (NAATs), to evaluate prepubertal children for N. gonorrhoeae or C. trachomatis, and the use of HIV postexposure prophylaxis are discussed.

SUMMARY

Any child or adolescent with a sexually transmitted infection should be evaluated for sexual abuse. Specific infections in prepubertal children, such as Neisseria gonorrhoeae or Chlamydia trachomatis, are due to abusive contact and should be reported to Child Protective Services. As the modes of transmission of anogenital infections with HPV and HSV are unclear, an evaluation for sexual abuse should be done. Although transmission of HIV after sexual abuse is rare, HIV postexposure prophylaxis must be administered in a timely fashion, and adequate outpatient support provided to facilitate compliance and follow-up.

Review of Gardasil

Human papillomavirus (HPV) is necessary for the development of cervical cancer. Cervical cancer is the second most common cancer in women worldwide but 80% occurs in developing countries, not countries with Pap screening programs. Pap screening programs in industrialized countries have reduced the incidence of cervical cancer to 4-8/100,000 women. HPV vaccines may be a promising strategy for cervical cancer in women without access to screening programs. In industrialized countries, the benefit of HPV vaccines focuses on individual abnormal Pap test reduction not cancer prevention. The focus of this review is to cover the side effects of Gardasil in perspective with the limited population benefit cervical cancer reduction in countries with organized Pap screening programs. In addition, information about Gardasil benefits, risks and unknowns for individual patient decision making for vaccination is presented. Gardasil offers protection against CIN 2+ lesions caused by HPV 16/18 and against genital warts caused by HPV 6/11 for at least 5 years. Combining Gardasil with repeated cytology screenings may reduce the proportion of abnormal cytology screens and hence reduce the associated morbidity with the subsequent colposcopies and excisional procedures.

Detection of antibodies against epidermodysplasia verruciformis-associated canine papillomavirus 3 in sera of dogs from Europe and Africa by enzyme-linked immunosorbent assay

The role of papillomaviruses (PVs) in the development of canine cancers is controversial. However, recently a novel canine PV (CPV3) was detected in a dog affected with a condition reminiscent of epidermodysplasia verruciformis (EV). The aim of the present study was to investigate the seroprevalence of CPV3 by using generic enzyme-linked immunosorbent assays (ELISAs) for the detection of antibodies against either canine oral PV (COPV) or CPV3. Therefore, the capsid proteins of both PV types were expressed as glutathione S-transferase fusion protein antigens and adsorbed to glutathione-casein-coated ELISA plates. After showing that PV type-specific antibodies could be detected in the sera from dogs with confirmed COPV or CPV3 infection, CPV3- and COPV-seropositive samples were detected in two sets of canine sera collected in Switzerland and South Africa, respectively. We found specific antibodies against COPV and CPV3 among the tested sera and also a large number that were positive for both antigens. The seroprevalences of PV antibodies of 21.9% (COPV) and 26.9% (CPV3) among the tested dogs from South Africa were higher than those among the dogs from Switzerland at 10.5% (COPV) and 1.3% (CPV3). Our data suggest a need for further CPV-related seroepidemiological surveys in different countries, especially in the context of clinical manifestations and possible breed predispositions. For this purpose, the newly developed ELISAs can be a useful tool.

Vaccination and screening programs: harmonizing prevention strategies for HPV-related diseases

HPV vaccine is an exciting promise of the preventive medicine. Although HPV-immunization programs still reveal a number of unanswered questions, they represent a novel opportunity for primary prevention against cervical cancer and other HPV-related pre-neoplastic and neoplastic diseases. It is reasonable that the short and long-term benefits of vaccination on cervical and vulvo-vaginal HPV-related pathology will emerge when assuring over time a clear and complete information to the community and harmonizing the prevention strategies. Indeed, HPV-vaccination programs will require an understanding of new paradigms of infection and cancer control, and thus will require a rationale integration with the currently operating screening systems.

High-risk human papilloma viruses (HPVs) were not detected in the benign skin lesions of a small number of children

AIM

Human papilloma virus (HPV) can be transmitted via sexual as well as nonsexual routes. Recently, 'high-risk' HPVs were detected in the oral mucosa of children in whose cases there was no suspicion of sexual abuse. This implies that HPV 16 and 18 have additional nonsexual modes of transmission in childhood, such as vertical transmission and autoinoculation.

METHODS

Using polymerase chain reaction (PCR) assays, we examined the skin tissues of 12 children with benign skin lesions, aged between 6 and 13 years, for the presence of HPV.

RESULTS

Among 12 biopsy skin specimens, no 'high-risk' HPV DNA was detected. Specific PCRs for HPV DNA 16 and 18 were also negative.

CONCLUSION

This preliminary case-control study indicates the absence of mucosal 'high-risk' HPV types in the benign skin lesions of children.

Seroprevalence of 34 human papillomavirus types in the German general population

The natural history of infections with many human papillomavirus (HPV) types is poorly understood. Here, we describe for the first time the age- and sex-dependent antibody prevalence for 29 cutaneous and five mucosal HPV types from 15 species within five phylogenetic genera (alpha, beta, gamma, mu, nu) in a general population. Sera from 1,797 German adults and children (758 males and 1,039 females) between 1 and 82 years (median 37 years) were analysed for antibodies to the major capsid protein L1 by Luminex-based multiplex serology. The first substantial HPV antibody reactions observed already in children and young adults are those to cutaneous types of the genera nu (HPV 41) and mu (HPV 1, 63). The antibody prevalence to mucosal high-risk types, most prominently HPV 16, was elevated after puberty in women but not in men and peaked between 25 and 34 years. Antibodies to beta and gamma papillomaviruses (PV) were rare in children and increased homogeneously with age, with prevalence peaks at 40 and 60 years in women and 50 and 70 years in men. Antibodies to cutaneous alpha PV showed a heterogeneous age distribution. In summary, these data suggest three major seroprevalence patterns for HPV of phylogenetically distinct genera: antibodies to mu and nu skin PV appear early in life, those to mucosal alpha PV in women after puberty, and antibodies to beta as well as to gamma skin PV accumulate later in life.

Serologic response to human papillomavirus 16 among Australian women with high-grade cervical intraepithelial neoplasia

This study evaluated the detection of human papillomavirus (HPV) 16 antibody in HPV 16-associated cervical intraepithelial neoplasia (CIN) in Australian women. Seroreactivity to HPV 16 L1 virus-like particles was assessed in patients with CIN 2 (n= 169) and CIN 3 (n= 229) lesions previously tested for the presence of HPV DNA. Seropositivity was significantly commoner in women with HPV 16 DNA-positive lesions (98/184) than in women with no HPV DNA in the lesion (15/47) or with HPV of types other than 16 in the lesion (43/167) (P= 0.0004). In addition, seropositivity was observed in 33% (55/169) of women with CIN 2 and 46% (106/229) of women with CIN 3, in keeping with the lower fraction of CIN 2 (57/169) than CIN 3 (127/229) biopsies positive for HPV 16 DNA. HPV 16 seropositivity is most common in women with HPV 16-associated CIN, but many patients with HPV-associated CIN 3 are seronegative, and HPV 16 seropositivity is common in women with CIN associated with other HPV types. Overall, HPV 16 serology is a poor predictor of presence of HPV 16-associated CIN 3 in patient population studied.

Human Papillomavirus Infection Among Sexually Active Young Women in the United States: Implications for Developing a Vaccination Strategy

OBJECTIVES

Population-level data on prevalence and distribution of human papillomavirus (HPV) types in the United States are necessary to guide optimal vaccination strategies.

STUDY

Urine specimens from 3262 women ages 18 to 25 in the National Longitudinal Study of Adolescent Health (Wave III) were tested and typed for HPV. Poststratification sampling weights generated nationally representative estimates.

RESULTS

Overall HPV prevalence was 26.9% and as high as 14.3% among women with 1 lifetime partner but did not vary by geographic region. High-risk types were detected in 20%; approximately 10% were infected with types in current candidate vaccines. HPV infection was independently associated with mixing sex with alcohol, a black partner, >3 lifetime sex partners, being single, and illegal drug use. Having a current sex partner and receptive oral sex were inversely associated with HPV.

CONCLUSION

HPV prevalence was high throughout the country, even among women with only 1 lifetime partner, suggesting early and widespread rather than targeted immunization of young women.

Chapter 6: Epidemiology and transmission dynamics of genital HPV infection

This chapter provides an overview of the epidemiology of human papillomavirus (HPV) infection, with a focus on the dynamics of sexual transmission. We explore concepts related to the spread of sexually transmitted infections, including population prevalence, duration of infectivity, patterns of sexual contacts, and transmissibility, including modifiers of susceptibility and infectivity. HPV prevalence and incidence are high in most studies, particularly amongst young women. There is strong evidence that transmission occurs primarily via sexual activity, most commonly vaginal and anal intercourse. Although the duration of infectivity may be short, current evidence suggests that HPV is highly transmissible. The implications of transmission dynamics for the success of future HPV vaccines are discussed.

Human Papillomavirus Infections of the Genital and Respiratory Tracts in Young Children

Human papillomavirus (HPV) causes papillomas (warts) on the skin and respiratory mucosal surfaces (laryngeal and oral papillomas) in addition to condyloma acuminata (anogenital warts). HPV has become one of the most common sexually transmitted diseases in adults. Vertical transmission from mother to infant during birth is well recognized. Laryngeal papillomas are the most common tumors of the larynx in children worldwide, and recurrent lesions are common occurrences. Anogenital warts in children are problematic in that child sexual abuse is a potential means of acquisition, but many cases are acquired perinatally. Postnatal acquisition by nonsexual means also can occur. The likelihood of sexual abuse as the mode of acquisition increases with increasing age in childhood. The virus infects primarily epithelial cells, where it can exist as a long-term latent infection that can reactivate or persist actively (even subclinically), with resultant accumulation of host chromosomal mutations. The latter accounts for the oncogenic potential of a number of HPV types, and childhood infections may lead to neoplasia later in life. Regression of papillomas over the course of months to years is the usual natural course. Numerous treatments are available, but most do not prevent persistent infection or problematic recurrences. Multivalent HPV vaccines have been developed, and early results of clinical trials appear to be very promising.