Human Papillomavirus Seroprevalence Research Articles

Cross-sectional study of HPV-16 infection in a population-based subsample of Hispanic adults

ObjectiveThis study aimed to estimate the prevalence and correlates of seropositivity to human papillomavirus (HPV)-16 in a subsample of adults who participated in the parent study Epidemiology of Hepatitis C...

DNA detection and seroprevalence of human papillomavirus in a cohort of adolescent women

ObjectivesHuman papillomavirus (HPV) infections are common in adolescent women, while the rare cancerous sequelae of HPV infections do not generally occur until the 4th or 5th decades of life. This...

Seroprevalence of Human Papillomavirus (HPV) Type 6 and 16 Vary by Anatomic Site of HPV Infection in Men

It is largely unknown if antihuman papillomavirus (HPV) serum antibody responses vary by anatomic site of infection in men. This study assessed type-specific anti-HPV serum antibody prevalence associated with corresponding HPV DNA detection in the external genitalia and the anal canal of 1,587 heterosexual men and 199 men who have sex with men (MSM). We observed that HPV 6 and 16 seroprevalence was higher in the presence of same HPV-type infection in the anal canal compared with same HPV-type infection in the external genitalia only, and among MSM compared with the heterosexual men. Seropositivity to HPV 6 was strongly associated with HPV 6 DNA detection in the anal canal but not in the external genitalia alone among both heterosexual men [adjusted prevalence ratio (APR), anal+/genital+ vs. anal-/genital-: 4.2, 95% confidence interval (CI), 11.7-10.5; anal+/genital- vs. anal-/genital-: 7.9 (95% CI, 3.7-17.0)] and MSM [APR, anal+/genital+ vs. anal-/genital-: 5.6 (95% CI, 2.7-11.9); anal+/genital- vs. anal-/genital-: 3.2 (95% CI, 2.1-4.9)]. Similar associations between seropositivity to HPV 16 and anal HPV 16 DNA detection were only observed in MSM [anal+/genital+ vs. anal-/genital-: 3.1 (95% CI, 2.0-5.0); anal+/genital- vs. anal-/genital-: 2.2 (95% CI, 1.3-3.5)]. Our data showed that seroprevalence varied by anatomic site of HPV infection, suggesting differences in epithelium type present at these anatomic sites may be relevant. Our finding is instrumental in advancing our understanding of immune mechanism involved in anatomic site-specific antibody response.

Age-Specific Seroprevalence of Human Papillomavirus 16, 18, 31, and 58 in Women of a Rural Town of Colombia

The study's objective was to estimate human papillomavirus (HPV) genotype-specific seroprevalence to determine population HPV exposure and inform vaccine policy. This study is a cross-sectional prevalence survey of 878 women of Pueblorrico, a rural town of Colombia. A standardized questionnaire was used to obtain information on demographic characteristics, sexual and reproductive history, and smoking habits. Seropositivity to HPV-16, -18, -31, and -58 was determined by virus-like particles in an enzyme-linked immunosorbent assay. Overall seropositivity to any HPV genotype was 27.9%. The combined seroprevalence of women 15 to 19 and 20 to 24 years old was 35.4% (95% confidence interval [CI], 25.9-46.2) and 36.0% (95% CI, 27.7-45.3), respectively. Seroprevalence for HPV-16 was 17% (95% CI, 14.6-19.6); for HPV-18, 9.8% (95% CI, 8.0-11.9); for HPV-31, 11.4% (95% CI, 9.5-13.7); and for HPV 58, 12.5% (95% CI, 10.5-14.9). Higher HPV seropositivity was associated with the lifetime number of occasional sexual partners (odds ratio, 3.05; 95% CI, 1.26-7.37) and having more than 2 regular sexual partners (odds ratio, 3.00; 95% CI, 1.21-7.45) in women younger than 44 and older than 45 years old, respectively. Use of oral contraceptives and tobacco/cigarettes was significantly associated with reduced HPV seropositivity in women older than 45 but not in women younger than 44 years old. Human papillomavirus seropositivity is associated with measures of sexual behavior, particularly a greater lifetime number of sexual partners. Hormonal and tobacco/cigarette use may be factors influencing the HPV seropositivity in women older than 45 years old.

Prevalence and Seroprevalence of Low-Risk Human Papillomavirus in Korean Women

Little is known about the prevalence and seroprevalence of low-risk human papillomavirus (HPV) and the risk factors for HPV infection in Korean women. We determined the prevalence of low-risk HPV among 902 women aged 20-59 yr and the seroprevalence of low-risk HPV subtypes 6 and 11 among 1,094 women aged 9-59 yr in the general population. Genital low-risk HPV DNA was assessed by liquid hybridization and polymerase chain reaction. Antibody titers against HPV 6 and 11 were measured by a multiplexed competitive luminex technique. The prevalence of genital low-risk HPV was 4.9%. It reached its highest peak of 10.3% at 20-29 yr of age and a second peak of 3.2% at 50-59 yr of age. The seroprevalence of HPV 6 or 11 was 9.4%. It reached its highest peak of 12.7% at 25-29 yr of age and a second peak of 12.3% at 50-59 yr of age. In multivariable analysis, the number of lifetime sexual partners and past history of sexually transmitted diseases were associated with the seroprevalence but not prevalence of HPV. It is suggested that younger women should receive prophylactic HPV vaccination before they become sexually active and exposed to HPV in their 20s. This study provides baseline data for developing HPV vaccination programs and monitoring vaccine efficacy in Korea.

Epidemiology of HPV genotypes in Uganda and the role of the current preventive vaccines: A systematic review.

BackgroundLimited data are available on the distribution of human papillomavirus (HPV) genotypes in the general population and in invasive cervical cancer (ICC) in Uganda. Yet, with the advent of preventive HPV vaccines that target HPV 16 and 18 responsible for causing about 70% of ICC cases in the world, such information is crucial to predict how vaccination and HPV-based screening will influence prevention of ICC.MethodsTo review the distribution of HPV infection and prevalent genotypes, electronic databases (e.g. PubMed/MEDLINE and HINARI) were searched for peer reviewed English articles on HPV infection up to November 30, 2010. Eligible studies were selected according to the following criteria: DNA-confirmed cervical or male genital HPV prevalence and genotypes, HPV incidence estimates and HPV seroprevalence among participants.ResultsTwenty studies were included in the review. Among HIV negative adult women, the prevalence of HR-HPV infections ranged from 10.2% -40.0% compared to 37.0% -100.0% among HIV positive women. Among HIV positive young women aged below 25 years, the prevalence of HR-HPV genotypes ranged from 41.6% -75.0% compared to 23.7% -67.1% among HIV negative women. Multiple infections with non vaccine HR-HPV genotypes were frequent in both HIV positive and HIV negative women. The main risk factors for prevalent HPV infections were age, lifetime number of sexual partners and HIV infection. Incident infections with HR-HPV genotypes were more frequent among adult HIV positive than HIV negative women estimated at 17.3 and 7.0 per 100 person-years, respectively. Similarly, incident HR-HPV among young women aged below 25 years were more frequent among HIV positive (40.0 per 100 person-years) than HIV negative women (20.3 per 100 person-years) women. The main risk factor for incident infection was HIV infection. HPV 16 and 18 were the most common genotypes in ICC with HPV 16/18 contributing up to 73.5% of cases with single infections.Among uncircumcised adult HIV positive males, HR-HPV prevalence ranged from 55.3% -76.6% compared to 38.6% -47.6% in HIV negative males. Incident and multiple HR-HPV infections were frequent in HIV positive males. Being uncircumcised was the main risk factor for both prevalent and incident HPV infection.ConclusionInfections with HR-HPV genotypes were very common particularly among HIV positive individuals and young women irrespective of HIV status. Given the high prevalence of HIV infection, HPV-associated conditions represent a major public health burden in Uganda. However, although the most common HPV genotypes in ICC cases in Uganda were those targeted by current preventive vaccines, there were a large number of individuals infected with other HR-HPV genotypes. Technology allowing, these other HR-HPV types should be considered in the development of the next generation of vaccines.

Prevalence of Human Papillomavirus Antibodies in Males and Females in England

Most studies of human papillomavirus (HPV) epidemiology have employed DNA testing, which measures current infections. Serum antibodies offer a longer-term marker of infection in individuals who seroconvert and can therefore provide additional information about the exposure of populations to HPV. Sera from a population-based sample of males and females aged 10 to 49 years, in England, were tested for type-specific HPV antibodies using a multiplexed competitive Luminex assay and previously defined cutoffs of 20, 16, 20, and 24 mMU mL for HPV 6, 11, 16, and 18, respectively. Seropositivity and geometric mean titers of seropositives were analyzed by HPV type, gender, and age. Catalytic models were developed to explore potential effects of antibody waning over time and changing risk of infection by age-cohort. Seroprevalence for HPV 6, 11, 16, and 18 was 16.4%, 5.7%, 14.7%, and 6.3%, respectively, among females and 7.6%, 2.2%, 5.0%, and 2.0%, respectively, among males. Seroprevalence in females was significantly higher than males (P < 0.001 for all types) and showed a decline in older ages that was not seen in males. There was no evidence of declining antibody titers with increasing age. Model results suggest that cohort effects mediated through changes in sexual behavior better explain the observed trend in seroprevalence than waning antibodies over time. Preimmunization HPV seroprevalence in England shows similar trends to reports from other developed countries. We find the lower seroprevalence in older females probably reflects changes in sexual behavior over the last few decades. This study provides baseline data to monitor the impact of the immunization programme.

Human Papillomavirus (HPV) 6, 11, 16, and 18 Seroprevalence Is Associated with Sexual Practice and Age: Results from the Multinational HPV Infection in Men Study (HIM Study)

Few human papillomavirus (HPV) serology studies have evaluated type-specific seroprevalence of vaccine HPV types in men. This study investigates seroprevalence of HPV 6, 11, 16, and 18, and associated risk factors in men residing in three countries (United States, Mexico, and Brazil). Data from 1,477 men aged 18 to 70 enrolled in the HPV Infection in Men Study (HIM Study) were analyzed. Serum antibody testing was performed with virus-like particle-based ELISA. Potential risk factors were assessed for individual HPV types by the use of logistic regression. Overall, HPV-6, 11, 16, and 18 seroprevalence was 14.8%, 17.3%, 11.2%, and 5.8%, respectively. Thirty-four percent of men were seropositive to one or more HPV types. When examined by sexual practice, 31.2% of men who had sex with women, 65.6% of men who had sex with men (MSM), and 59.4% of men who had sex with both men and women (MSMW) were seropositive to one or more HPV types. Seroprevalence increased with age among young-to-middle-aged men with significant upward age trends observed for HPV 11, 16, and 18. Men with multiple lifetime male anal sex partners were 2 to 4 times more likely to be HPV 6 or 11 seropositive and 3 to 11 times more likely to be HPV 16 or 18 seropositive. Our data indicate that exposures to vaccine HPV types were common in men and highly prevalent among MSM and MSMW. Our study provides strong evidence that the practice of same-sex anal intercourse is an independent risk factor for seroprevalence of individual vaccine HPV types. Examination of antibody responses to HPV infections at various anatomic sites in future studies is needed to elaborate on the mechanism.

Seroprevalence of human papillomavirus 6, 11, 16, and 18 in young primiparous women in Sao Paulo, Brazil.

Data on epidemiology of HPV infection are needed for the development of human papillomavirus (HPV) vaccine recommendations, especially in countries where HPV vaccination is not yet included in public vaccination programs. The aim of this study was to determine the prevalence of serum antibodies to HPV types 6, 11, 16, and 18 and associated factors among young women after birth of the first child. This cross-sectional study was carried out in a large public maternity hospital in Sao Paulo, Brazil. Three hundred one women aged 15 to 24 years who gave birth to their first child were recruited between 43 and 60 days after delivery. Seroprevalence was performed using a type-specific enzyme-linked immunosorbent assay based on HPV Late protein 1 viruslike particles. The association of seroreactivity with these 4 HPV types with selected demographic and behavioral factors was assessed by Generalized Linear Model analysis. Fifty-eight (19.3%) women (95% confidence interval, 15.0%-24.2%) had antibodies to any of the 4 viruslike particles tested. The overall seroprevalence rates of the HPV types were: HPV16, 9.0%; HPV18, 7.0%; and HPV 6+11, 7.7%, which are targeted by the HPV prophylactic vaccines. In the multivariate analysis, only age (inversely, P = 0.044 for trend) and previous sexually transmitted disease (P = 0.008) were 2 factors independently associated with HPV seropositivity. These data offer additional information on the epidemiology of HPV in a group of young Brazilian women after first delivery and contribute to establish a baseline of HPV seroprevalence against which post-HPV vaccine era seroprevalence can be compared.

Age-specific HPV seroprevalence among young females in The Netherlands

ObjectivesTo obtain insight into the age-specific seroprevalence for human papillomavirus (HPV) 6, 11, 16 and 18 among females before introduction of HPV vaccination in The Netherlands.MethodsIn a population-based study in...

HPV 6/11, 16, 18 Seroprevalence in Men in Two US Cities

A vaccine to prevent human papillomavirus (HPV) 6, HPV 11, HPV 16, or HPV 18 and associated diseases is licensed for females, and it may be licensed for men in the future. There are limited data on HPV 6/11, 16, and/or 18 seroprevalence in men. A total of 490 men aged 18 to 40 years were enrolled in a study of HPV in men in Tucson, AZ, and Tampa, FL. Enrolled men completed a self-administered questionnaire, and HPV serology was performed using HPV 6/11, 16, and 18 VLP assays. Overall, seroprevalence to HPV 16 was 12.1%, HPV 6/11 was 9.7%, and to HPV 18 was 5.4%. Seroprevalence to HPV 6/11, 16, and/or 18 was 21% and was highest among 35 to 40 year olds (48%); prevalence in this age group was significantly higher compared to the 18 to 24 year olds (adjusted odds ratio (aOR) 6.8, 95% confidence interval (CI) 3.7, 12.8). Independent predictors of seropositivity to HPV 6/11, 16, and/or 18 were older age, greater number of female sex partners in the past 3 months, and current smoking. HPV vaccine-type seroprevalence was highest in 35 to 40 year old men. These data on the epidemiology of HPV seroprevalence in men are useful for discussions regarding recommendations for HPV vaccine if licensed for use in men.

The seroprevalence of human papillomavirus by immune status and by ethnicity in London

BackgroundThe natural history of cutaneous HPV is unclear and in particular, seroprevalence among individuals with different levels of immune function and ethnicity is unknown. As part of a study of cutaneous squamous cell carcinoma (SCC) and HPV among organ transplant recipients (OTR) from London, we investigated the seroprevalence and risk factors for 34 HPV types (detected using Luminex technology) among 409 OTR patients without skin cancer (243 Caucasians and 166 non-Caucasians), 367 individuals with end stage renal failure on dialysis (222 Caucasians and 145 non-Caucasians) and 152 immunocompetent (IC) individuals without skin cancer (102 Caucasians and 50 non-Caucasians) to compare the HPV seroprevalence in patients with differing immune status and ethnicity. In total, seroprevalence data from 928 individuals, all from London, was available.ResultsOverall, no difference between HPV seroprevalence by immune status was observed (P = 0.3) among Caucasian or among non-Caucasian individuals, with seroprevalence varying from 87% to 94% across different immune status and ethnic groups. Those individuals seropositive to multiple types of one genus were more likely to be seroreactive to multiple types of another genus, independent of immune status or ethnicity. Lower seroprevalence for gammaHPV 4, and to a lesser extent gammaHPV 48, were observed among OTR compared to IC and dialysis patients. Higher seroprevalence against antibodies to betaHPV 93 were detected more frequently in non-Caucasians than Caucasians whereas muHPV 1 and, to a lesser extent, gammaHPV 4 were found more frequently among Caucasians - these findings were independent of immune status. Within non-Caucasian subgroups, the seroprevalence of 8 HPV (alpha-mucosal HPV16 and 13, alpha-cutaneous HPV7 and 2, betaHPV8, 17, 23 and 38) was significantly (P < 0.02) higher in Black compared to Asian patients. HPV16 being sexually transmitted, this might suggest a potential sexual route of transmission for some beta HPV types.ConclusionWe did not observe major disturbance in antibody response between immunocompetent, dialysis and OTR individuals, but significant differences in HPV seroprevalence were identified according to ethnicity. Further research is needed to clarify the natural history of cutaneous HPV, particularly given the growing research interest in its possible role in the pathogenesis of cutaneous SCC.

Antibody responses to 26 skin human papillomavirus types in the Netherlands, Italy and Australia

Solar UV radiation is the main risk factor for cutaneous squamous cell carcinoma (SCC), but infections with skin human papillomavirus (HPV) types have also been linked to the development of SCC. Little is known about the natural history of these infections and whether the seroprevalence of skin HPV types is affected by ambient or individual levels of sun exposure. This study investigated this by analysing sera for antibodies to 26 skin HPV types from five phylogenetic genera obtained from 807 healthy individuals from the Netherlands, Italy and Australia, countries with strong differences in sunlight intensity. Overall HPV seroprevalence was similar across the three countries (50-57 % for beta-HPV types, 40-48 % for gamma-HPV types), and the most frequent beta-HPV and gamma-HPV types were the same in all countries. The highest seroprevalences for 24 of the 26 skin HPV types were observed in Italy (14 types) and Australia (ten types). Seroprevalence among men was generally higher than among women, and the male sex was significantly associated with both beta-HPV [odds ratio (OR) 2.81, 95 % confidence interval (CI) 1.64-4.82] and gamma-HPV (OR 2.42, 95 % CI 1.40-4.18) antibodies in Australia. The only measure of sun sensitivity or UV exposure significantly associated with skin HPV seroprevalence was found for weekend sun exposure in Australia and beta-HPV antibodies. It was concluded that type spectra and HPV seroprevalence are similar in countries with different sunlight intensity, and that levels of UV exposure do not play a strong role in the development of skin HPV antibodies in this study population.

Dynamics of human papillomavirus serology in women followed up for 36 months after pregnancy

We determined L1 antibodies for human papillomavirus (HPV) types 6, 11, 16, 18 and 45 by multiplex serology in our prospective HPV family study. We report seroprevalence, seroconversion and antibody decay in 290 women (mean age, 25.5 years) sampled before delivery and at 12, 24 and 36 months of follow-up. Multiplex HPV genotyping of the baseline oral and genital scrapings was performed. At baseline, seroprevalence of HPV 6, 11, 16, 18 and 45 was 53.3, 21.5, 34.9, 21.5 and 9.0%, respectively. Seropositivity for low-risk HPV (LR-HPV) was associated significantly with age at onset of sexual activity (P=0.001), number of sexual partners until age 20 (P=0.018), lifetime number of sexual partners (P=0.0001), history of genital warts (P=0.0001) and being seropositive for high-risk (HR) HPV (P=0.0001). The same covariates also predicted seropositivity for HR-HPV. During follow-up, 26.7, 13.9, 17.0, 16.8 and 6.6% of the women seroconverted to L1 antigen of HPV 6, 11, 16, 18 and 45, respectively, between 18.2 and 23.8 months. Independent predictors of seroconversion to LR-HPV were unemployment (P=0.019) and absence of anal sex practice (P=0.031), and to HR-HPV, absence of smoking history and lifetime number of sexual partners. Decay of HPV 6, 11, 16, 18 and 45 antibodies was observed in 2.3, 4.0, 5.3, 4.5 and 1.5 % of the women, respectively, with decay time varying from 27.2 to 35.8 months. These data imply that (i) a substantial proportion of young women are seropositive for both LR- and HR-HPV types, (ii) they frequently undergo seroconversion within 18-24 months, predicted by common covariates, and (iii) antibody decay over 3 years is rare.

Human Papillomavirus Infection in Ulaanbaatar, Mongolia: A Population-Based Study

Data on human papillomavirus (HPV) and cervical cancer burden in Central Asia are scarce. To investigate HPV infection in Ulaanbaatar, the capital of Mongolia, we obtained cervical cell specimens from a population of 969 women ages 15 to 59 years. DNA of 44 HPV types was detected using a GP5+/6+ PCR-based assay. Seropositivity for L1 proteins of HPV 16, 18, 31, 33, 45, 52, and 58 was assessed using multiplex HPV serology. Cytologic abnormalities were detected in 127 women (13.1%), among whom 6 cervical intraepithelial neoplasia grade 3 and 2 invasive cervical cancers were diagnosed. Overall HPV DNA prevalence was 35.0%, being highest (48.5%) in women ages <25 years. High-risk types were detected in 24.5% of women. HPV DNA prevalence declined with age but remained >25% in all age groups. HPV seroprevalence was also very high (38.0%) and increased steadily from 33.2% to 48.9% in women ages <25 and 50 to 59 years, respectively. However, the proportion of women positive for both HPV markers of any individual HPV type was low. HPV16 was the most frequently detected type by PCR (6.1%), serology (23.0%), or both (2.1%). Lifetime number of sexual partners and induced abortions were shown to be directly associated with HPV DNA and/or seroprevalence. HPV prevalence in Ulaanbaatar was higher than that detected by similar HPV testing protocols in other populations in Asia or elsewhere and would suggest an important, yet unquantified, cervical cancer burden. Improving cervical cancer prevention, through screening and HPV vaccination, is an important public health issue for Mongolia.

Seroepidemiology of Human Papillomavirus Type 11 in the United States: Results From the Third National Health and Nutrition Examination Survey, 1991–1994

The national seroprevalence of the nononcogenic human papillomavirus (HPV) type 11, one of the types targeted by the quadrivalent HPV vaccine, has not been evaluated in the United States. The objectives of this study were to estimate the national seroprevalence and evaluate predictors of HPV-11 seropositivity. We tested serum samples for HPV-11 antibodies and analyzed questionnaire data from the second phase of the National Health and Nutrition Examination Survey III, 1991--1994. Seroprevalence estimates were weighted to represent the US population. : Overall seroprevalence of HPV-11 infection was 4.7%. Seroprevalence was significantly higher among females (5.7%) than among males (3.6%). Independent predictors of HPV-11 seropositivity included sex, race/ethnicity, lifetime number of sex partners, education, and HPV-16 seropositivity. This study represents the most comprehensive picture of HPV-11 infection in the United States to date, and provides baseline data on the prevalence of HPV-11 before availability of the quadrivalent HPV vaccine.

Seroprevalence and Risk Factors for Human Papillomavirus in Taiwan

The aim of the study was to tailor a future Human papillomavirus (HPV) vaccine campaign and to help perform early primary prevention of HPV infection in Taiwan, where the incidence of cervical cancer is high. A cross-sectional survey was conducted of 826 female students, ages 10, 13, 16 and 19-22 years. A self-administered questionnaire was used to collect information on risk factors for HPV infection. Serum samples were tested for antibodies to HPV 16 capsids using a virus-like particle-based enzyme-linked immunosorbence assay. The age-adjusted odds ratio of HPV seropositivity was calculated for each risk factor by multiple logistic regression analysis. HPV 16 antibodies were detected in 13 (1.6%) of 826 participants. The HPV 16 seroprevalence was 0.35% (1/287), 0.85% (2/235), 3.2% (6/185) and 3.4% (4/119), respectively, for age groups of 10, 13, 16 and 19-22 years. In the multiple regression analysis, the history of having sexual activity was the most significant risk predictor for HPV 16 seropositivity. The seroprevalence of HPV 16 increased dramatically among high school seniors and university students, and was significantly associated with sexual activity. Vaccination against HPV is suggested to be undertaken in early adolescence, before 16 years of age and prior to sexual debut.

Serologic Response to Oncogenic Human Papillomavirus Types in Male and Female University Students in Busan, South Korea

In the absence of genital samples, human papillomavirus (HPV) serology may be useful to assess HPV infection in young men and women. HPV seroprevalence and determinants of seropositivity were assessed in 817 female and 518 male university students in Busan, South Korea, of whom 74% and 44%, respectively, reported never having had penetrative sexual intercourse. Type-specific HPV DNA status, assessed by a short PCR fragment primer set, was available from genital samples. Seropositivity to L1 proteins of HPV types 16, 18, 31, 33, 45, 52, and 58 were assessed using multiplex HPV serology. Among women, HPV seroprevalence was significantly higher among sexually active (26.1%) than nonsexually active students [11.1%, odds ratio (OR) = 2.9; 95% confidence interval (95% CI), 1.8-4.7], although the association was weaker than that for HPV DNA prevalence (OR, 14; 95% CI, 4.7-42). Furthermore, HPV seroprevalence was higher among HPV DNA-positive (24%) than HPV DNA-negative women (13%), and there was a positive correlation of type-specific seroprevalence with the presence of HPV DNA of the same type. In contrast, HPV seropositivity among men was not associated with sexual behavior or the presence of HPV DNA. Seroprevalence correlates with genital HPV exposure in young women, but its meaning in young men is unclear.

Human Papillomavirus Seroprevalence Among Young Male and Female Drug Users

To determine seroprevalence and correlates of exposure to HPV 16, 18, and 53 among 15- to 30-year-old drug users in Baltimore, MD. Young, newly initiated injection and noninjection drug users underwent a behavioral risk assessment and HPV serology testing. Sex-specific analyses were performed comparing seropositive and seronegative participants using chi2, Mann-Whitney tests, and logistic regression. Participants (n = 553) were 43.0% female, 40.2% African American, and median age was 24 years. HPV seroprevalence among females and males, respectively, was: HPV-16, 38.2% and 7.0%; HPV-18, 42.4% and 7.3%; and HPV-53, 27.7% and 5.1%. Correlates of HPV seropositivity among females included being African American and anal sex, and among males, having had sex with another male. HPV seroprevalence was high among young drug users and significantly higher among females than males, supporting previous findings. Further research is required to fully understand HPV risk factors among men and the contribution of anal transmission in women.

Seroprevalence of human papillomavirus types 16 and 18 in the general population in Taiwan: Implication for optimal age of human papillomavirus vaccination

Background The optimal age for administration of recently approved prophylactic human papillomavirus (HPV) vaccines remains undetermined. Objectives The aim of the study was to explore the age-specific seroprevalence of HPV 16 and 18 in the general population to design an HPV vaccination campaign for Taiwan. Study design HPV seroprevalence was assessed by virus-like particle (VLP)-based ELISA in 1702 plasma samples collected in 1999. Results The sample population consisted of 1000 (58.8%) females and 702 (41.2%) males; age ranged from 17 days to 86 years. The age-specific distributions reveal a significant rise in HPV 16 seropositivity commencing at 19–25 years of age and peaking at >60 years. The trend of seropositivity increase with age was also highly significant for HPV 18 ( P Trend < 0.0001). Males had lower overall seroprevalence in gender comparison (7.6% versus 3.85% for HPV 16, 3.9% versus 2.71% for HPV 18), were older at seroconversion (19–25 years versus 26–30 years) with a more obvious seropositivity nadir in middle age. Conclusion The age-specific seroprevalence of HPV 16 and 18 increases in young adults after the age of 18 years, with gender distribution varying. We conclude that the optimal age for universal HPV vaccination in Taiwan is 15 years or below.