Seroresponses to virus-like particles of human papillomavirus types 16, 18, 31, 33, and 45 in San people of Southern Africa

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.

Human papillomavirus (HPV) L1 and L1-L2 virus-like particle-based multiplex assays for measurement of HPV virion antibodies

Humoral immunity to human papillomavirus (HPV) has not been fully characterized, and there is currently no standard serologic test for the measurement of HPV antibodies. Most HPV serologic assays developed to date are based on virus-like particles (VLPs) of the major HPV capsid protein, L1. We sought to compare the performance of a multiplex HPV L1 VLP-based serologic assay to that of an assay based on VLPs comprised of both L1 and the minor capsid, L2. We developed HPV L1 VLP and L1-L2 VLP-based multiplex seroassays for the detection of HPV type 16 (HPV16) and HPV18 virion binding antibodies using Luminex fluorescent bead technology. We compared the performance of these assays to that of established pseudovirion-based neutralization and L1 VLP-based enzyme-linked immunosorbent assays (ELISAs). A total of 391 serum specimens from unvaccinated adult males and females were tested. The L1 and L1-L2 VLP multiplex seroassays each demonstrated substantial agreement with both the neutralization assays and the ELISAs for the detection of HPV16 antibodies (κ = 0.60 to 0.64). However, the L1-L2 VLP seroassay demonstrated better agreement with neutralization assays for the detection of HPV18 antibodies than the L1 VLP seroassay (κ = 0.74 and 0.43, respectively). L1 and L1-L2 VLP seroassays showed excellent agreement with one another for the detection of HPV16 antibodies (κ = 0.86) but only moderate agreement for HPV18 antibodies (κ = 0.44). The HPV L1-L2 VLP seroassay performs well for the concurrent measurement of HPV16 and -18 antibodies in large numbers of samples and may be extended to include other HPV types.

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.

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.

Genotype distribution of cervical human papillomavirus DNA in women with cervical lesions in Bioko, Equatorial Guinea

Background

The HVP vaccine is a useful tool for preventing cervical cancer. The purpose of this study is to determine the most frequent HPV genotypes in Equatorial Guinea in order to develop future vaccination strategies to apply in this country.

Methods

A campaign against cervical cancer was carried out in the area on a total of 1,680 women. 26 of the women, following cytological screening, were treated surgically with a loop electrosurgical excision procedure (LEEP). Cases were studied histologically and were genotyped from paraffin blocks by applying a commercial kit that recognized 35 HPV types.

Results

Cytological diagnoses included 17 HSIL, 1 LSIL, 5 ASC-H and 3 AGUS. Histological diagnosis resulted in 3 cases of microinvasive squamous cell carcinoma stage IA of FIGO, 9 CIN-3, 8 CIN-2, 2 CIN-1, 3 flat condylomas and mild dysplasia of the endocervical epithelium. Fifteen of twenty-five cases genotyped were positive for HPV (60%). HPV 16 and 33 were identified in four cases each, HPV 58 in two other cases, and HPV 18, 31, 52, and 82 in one case, with one HPV 16 and 58 coinfection.

Conclusion

The frequency of HPV types in the African area varies in comparison to other regions, particularly in Europe and USA. Vaccination against the five most common HPV types (16, 33, 58, 18, and 31) should be considered in the geographic region of West Africa and specifically in Equatorial Guinea.

Human papillomavirus types 16 and 18 DNA load in relation to coexistence of other types, particularly those in the same species

BACKGROUND

Infection with multiple human papillomavirus (HPV) types is common. However, it is unknown whether viral DNA load is related to the coexistence of other types.

METHODS

Study subjects were 802 and 303 women who were positive for HPV16 and HPV18, respectively, at enrollment into the Atypical Squamous Cells of Undetermined Significance and Low-Grade Squamous Intraepithelial Lesion Triage Study. HPV16 and HPV18 E7 copies per nanogram of cellular DNA in cervical swab samples were measured by real-time PCR in triplicate.

RESULTS

Concurrent coinfection was common in this population of women with minor cervical lesions; multiple HPV types were detected in 573 (71.4%) of 802 HPV16-positive women and 227 (74.9%) of 303 HPV18-positive women. The adjusted odds ratio associating coinfection with per 1 log unit increase in HPV16 DNA load was 0.78 (95% confidence interval, 0.68-0.89); it was 0.64 (95% confidence interval, 0.52-0.79) for a similar analysis of HPV18 DNA load. Women with, compared with without, coinfection of A9 species types possessed a significantly lower HPV16 DNA load (P < 0.001), whereas women with, compared with without, coinfection of A7 species types possessed a significantly lower HPV18 DNA load (P = 0.001). A trend of decrease in HPV16 DNA load with increasing number of the coexisting non-HPV16 A9 species types was statistically significant (P(trend) = 0.001).

CONCLUSION

Coinfection with other types was associated with lower HPV16 and HPV18 DNA load. The extent of reduction was correlated to phylogenetic distance of the coexisting types to HPV16 and HPV18, respectively.

The seroprevalence of IgG antibodies to human papillomavirus (HPV) types HPV-16, HPV-18, and HPV-11 capsid-antigens in mothers and their children

Human papillomavirus (HPV) types causing anogenital lesions and cancer are accepted as being sexually transmitted. The methods whereby children acquire these anogenital type HPV infections are unclear. The present study determined the prevalence of anti-HPV-16, HPV-11 and HPV-18 IgG antibodies in mothers and their children in an attempt to identify evidence of HPV transmission from mother to child. HPV virus-like particles (VLP) VLP-16, VLP-11 and VLP-18 were used in enzyme-linked immunosorbent assay to identify IgG antibodies in serum from 100 mothers and their 111 children. Antibodies to VLP-16, VLP-11 and VLP-18 were found in serum from 17%, 21% and 16% of mothers, respectively and seroprevalences were 9%, 11.7% and 9.9%, respectively amongst the children. Of the 111 children, 23 (20.7%) showed antibodies to one or more of the three HPV types tested. Seven of these (30.4%) HPV IgG positive children had the same antibodies to one or more HPV types as their mothers. The prevalence of HPV-11 was similar in children of seropositive compared with seronegative mothers (14% and 11%, respectively). The prevalence of HPV-16 and HPV-18 was higher in children of seropositive mothers compared with seronegative mothers (for HPV-16, 18% and 7%, respectively, P = 0.1, for HPV-18, 19% and 8%, respectively, P = 0.2). None of these differences were statistically significant indicating a lack of correlation between antibodies in mothers and children and no evidence to support vertical or horizontal mother to child transmission of HPV infection. Indications were of multiple sources of HPV infection in the children.

Sustained efficacy up to 4.5 years of a bivalent L1 virus-like particle vaccine against human papillomavirus types 16 and 18: follow-up from a randomised control trial

BACKGROUND

Effective vaccination against HPV 16 and HPV 18 to prevent cervical cancer will require a high level of sustained protection against infection and precancerous lesions. Our aim was to assess the long-term efficacy, immunogenicity, and safety of a bivalent HPV-16/18 L1 virus-like particle AS04 vaccine against incident and persistent infection with HPV 16 and HPV 18 and their associated cytological and histological outcomes.

METHODS

We did a follow-up study of our multicentre, double-blind, randomised, placebo-controlled trial reported in 2004. We included women who originally received all three doses of bivalent HPV-16/18 virus-like particle AS04 vaccine (0.5 mL; n=393) or placebo (n=383). We assessed HPV DNA, using cervical samples, and did yearly cervical cytology assessments. We also studied the long-term immunogenicity and safety of the vaccine.

FINDINGS

More than 98% seropositivity was maintained for HPV-16/18 antibodies during the extended follow-up phase. We noted significant vaccine efficacy against HPV-16 and HPV-18 endpoints: incident infection, 96.9% (95% CI 81.3-99.9); persistent infection: 6 month definition, 94.3 (63.2-99.9); 12 month definition, 100% (33.6-100). In a combined analysis of the initial efficacy and extended follow-up studies, vaccine efficacy of 100% (42.4-100) against cervical intraepithelial neoplasia (CIN) lesions associated with vaccine types. We noted broad protection against cytohistological outcomes beyond that anticipated for HPV 16/18 and protection against incident infection with HPV 45 and HPV 31. The vaccine has a good long-term safety profile.

INTERPRETATION

Up to 4.5 years, the HPV-16/18 L1 virus-like particle AS04 vaccine is highly immunogenic and safe, and induces a high degree of protection against HPV-16/18 infection and associated cervical lesions. There is also evidence of cross protection.

Human papillomavirus-specific antibody status in oral fluids modestly reflects serum status in human immunodeficiency virus-positive individuals

Serological assays are valuable tools for studies of the epidemiology of human papillomaviruses (HPVs). The efficacy of a less invasive oral-fluid assay for detection of HPV antibodies was examined. Matched serum, saliva, and oral mucosal transudate (OMT) specimens collected from 150 human immunodeficiency virus-seropositive patients were tested for immunoglobulin G antibodies against HPV-6 and HPV-11 combined (HPV-6/11) and HPV-16 capsids. Antibodies to HPV were detected in both types of oral specimens. Seroprevalence rates were 55% for HPV-6/11 and 37% for HPV-16, whereas oral prevalence rates were significantly lower (for HPV-6/11 in saliva, 31%, and in OMT, 19%; for HPV-16 in saliva, 19%, and in OMT, 17%). HPV antibody detection in OMT more accurately reflected the presence of antibodies in serum than did HPV antibody detection in saliva. More stringent saliva assay cutpoints yielded stronger associations between oropositivity and seropositivity; less stringent OMT cutpoints yielded stronger associations between oropositivity and seropositivity. Although HPV antibodies were detected in oral fluids, further optimization of the assay is necessary before oral-fluid testing can be implemented as a reliable alternative to serum testing for HPV.

Serologic response to human oncogenic papillomavirus types 16, 18, 31, 33, 39, 58 and 59 virus-like particles in colombian women with invasive cervical cancer

The serologic response against virus-like particles (VLP) from 7 high risk genital papillomaviruses was investigated by ELISA in 147 Colombian women with invasive cervical cancer and 147 age-matched cytologically normal and HPV-DNA negative women. Anti-VLP antibodies were detected in 82% of the invasive cervical cancer patients and in 56% of the controls. Detection of antibodies against multiple HPV types is the rule and the presence of high antibody titers was associated with higher survival of cancer patients. Higher anti-VLP seroprevalence was observed in younger cancer patients. In those followed serologically for 1 year, antibodies generally remained at the same level. However, in some patients an increase or decrease in antibody levels occurred simultaneously for multiple HPV types, suggesting cross-reactivity between the HPV types investigated. Investigation of seroreactivity between 8 high risk HPVs suggested that there is some cross-reactivity between phylogeneticaly-related types such as 16, 31, 33 and 58; and 18, 45 and 59. In conclusion, our results confirmed (i) the high rate of HPV infections in Colombia, both in patients with cervical cancer and in the general population, and the particularly high rate of infections due to HPV 31 and 58; and (ii) the validity of anti-VLPs as a marker of present or past HPV infection. The simultaneous appearance or disappearance of antibodies against multiple HPV VLPs suggests that the antibodies detected by ELISA are not always type specific.