Anna-Lise Williamson

Identification of HPV16 Lineages in South African and Mozambican Women with Normal and Abnormal Cervical Cytology

Background: Human papillomavirus 16 (HPV16) is an oncogenic virus responsible for the majority of invasive cervical cancer cases worldwide. Due to genetic modifications, some variants are more oncogenic than others. We analysed the HPV16 phylogeny in HPV16-positive cervical Desoxyribonucleic Acid (DNA) samples collected from South African and Mozambican women to detect the circulating lineages. Methods: Polymerase chain reaction (PCR) amplification of the long control region (LCR) and 300 nucleotides of the E6 region was performed using HPV16-specific primers on HPV16-positive cervical samples collected in women from South Africa and Mozambique. HPV16 sequences were obtained through Next Generation Sequencing (NGS) methods. Geneious prime and MEGA 11 software were used to align the sequences to 16 HPV16 reference sequences, gathering the A, B, C, and D lineages and generating the phylogenetic tree. Single nucleotide polymorphisms (SNPs) in the LCR and E6 regions were analysed and the phylogenetic tree was generated using Geneious Prime software. Results: Fifty-eight sequences were analysed. Of these sequences, 79% (46/58) were from women who had abnormal cervical cytology. Fifteen SNPs in the LCR and eight in the E6 region were found to be the most common in all sequences. The phylogenetic analysis determined that 45% of the isolates belonged to the A1 sublineage (European variant), 34% belonged to the C1 sublineage (African 1 variant), 16% belonged to the B1 and B2 sublineage (African 2 variant), two isolates belonged to the D1–3 sublineages (Asian-American variant), and one to the North American variant. Conclusions: The African and European HPV16 variants were the most common circulating lineages in South African and Mozambican women. A high-grade squamous intraepithelial lesion (HSIL) was the most common cervical abnormality observed and linked to European and African lineages. These findings may contribute to understanding molecular HPV16 epidemiology in South Africa and Mozambique.

Vaccine and Non-Vaccine HPV Types Presence in Adolescents with Vertically Acquired HIV Five Years Post Gardasil Quadrivalent Vaccination: The ZIMGARD Cohort

Background: Human papillomavirus (HPV) vaccination programs are a key intervention in protecting individuals against HPV-related disease. HIV1-infected individuals are at increased risk of HPV-associated cancers. This study was conducted to evaluate the potential role of prophylactic HPV vaccines in preventing new HPV infections among participants with perinatally acquired HIV who received the quadrivalent HPV vaccine at least five years before this study. Methods: This cross-sectional study was conducted at Newlands Clinic, Harare, Zimbabwe. The clinic provided the Gardasil quadrivalent HPV vaccine (4vHPV) to 624 adolescents living with HIV starting in December 2015. Vaginal and penile swabs were collected and tested for HPV types from the study participants who had received the 4vHPV vaccine 5–6 years before enrolment. Results: We present the results of 98 participants (44.6% female) vaccinated at a median age of 15 years (IQR 12–16). The mean amount of time since vaccination was 6 years (SD: ±0.4). The HPV-positive rate amongst the analyzed swabs was 69% (68/98). Among 30/98 (31%) HPV-positive participants, 13/98 (13%) had low-risk HPV types, and 17/98 (17%) had high-risk HPV types. Twelve participants tested positive for HPV18, only one participant tested positive for HPV16, and an additional four (4.3%) tested positive for either type 6 or 11, with respect to vaccine-preventable low-risk HPV types. Conclusion: The Gardasil quadrivalent HPV vaccine (4vHPV) was expected to protect against infection with HPV types 16, 18, 6, and 11. We demonstrated a possible waning of immunity to HPV18 in 17% of the participants, and an associated loss in cross-protection against HPV45. We observed a relatively high prevalence of ‘opportunistic non-vaccine HPV types’ or ‘ecological niche occupiers’ in this cohort, and suggest further research on the involvement of these types in cervical and other genital cancers. Our study is one of the few, if not the first, to report on HPV vaccine immunoprotection among people living with HIV (PLWH), thereby setting a baseline for further studies on HPV vaccine effectiveness among PLWH.

Acceptability of self- collection for human papillomavirus detection in the Eastern Cape, South Africa

Human papillomavirus (HPV) testing on vaginal self-collected and cervical clinician-collected specimens shows comparable performance. Self-sampling on FTA cards is suitable for women residing in rural settings or not attending regular screening and increases participation rate in the cervical cancer screening programme. We aimed to investigate and compare high-risk (HR)-HPV prevalence in clinician-collected and self-collected genital specimens as well as two different HPV tests on the clinician collected samples. A total of 737 women were recruited from two sites, a community health clinic (n = 413) and a referral clinic (n = 324) in the Eastern Cape Province. Cervical clinician-collected (FTA cards and Digene transport medium) and vaginal self-collected specimens were tested for HR-HPV using the hpVIR assay (FTA cards) and Hybrid Capture-2 (Digene transport medium). There was no significant difference in HR-HPV positivity between clinician-collected and self-collected specimens among women from the community-based clinic (26.4% vs 27.9%, p = 0.601) or the referral clinic (83.6% vs 79.9%, p = 0.222). HPV16, HPV35, and HPV33/52/58 group were the most frequently detected genotypes at both study sites. Self-sampling for HPV testing received a high positive response of acceptance (77.2% in the community-based clinic and 83.0% in referral clinic). The overall agreement between hpVIR assay and HC-2 was 87.7% (k = 0.754). The study found good agreement between clinician-collected and self-collected genital specimens. Self-collection can have a positive impact on a cervical screening program in South Africa by increasing coverage of women in rural areas, in particular those unable to visit the clinics and women attending clinics where cytology-based programs are not functioning effectively.

Distribution of Human Papillomavirus (HPV) Genotypes in HIV-Negative and HIV-Positive Women with Cervical Intraepithelial Lesions in the Eastern Cape Province, South Africa

South African women have a high rate of cervical cancer cases, but there are limited data on human papillomavirus (HPV) genotypes in cervical intraepithelial neoplasia (CIN) in the Eastern Cape province, South Africa. A total of 193 cervical specimens with confirmed CIN from women aged 18 years or older, recruited from a referral hospital, were tested for HPV infection. The cervical specimens, smeared onto FTA cards, were screened for 36 HPV types using an HPV direct flow kit. HPV prevalence was 93.5% (43/46) in CIN2 and 96.6% (142/147) in CIN3. HIV-positive women had a significantly higher HPV prevalence than HIV-negative women (98.0% vs. 89.1%, p = 0.012). The prevalence of multiple types was significantly higher in HIV-positive than HIV-negative women (p = 0.034). The frequently detected genotypes were HPV35 (23.9%), HPV58 (23.9%), HPV45 (19.6%), and HPV16 (17.3%) in CIN2 cases, while in CIN3, HPV35 (22.5%), HPV16 (21.8%), HPV33 (15.6%), and HPV58 (14.3%) were the most common identified HPV types, independent of HIV status. The prevalence of HPV types targeted by the nonavalent HPV vaccine was 60.9% and 68.7% among women with CIN2 and CIN3, respectively, indicating that vaccination would have an impact both in HIV-negative and HIV-positive South African women, although it will not provide full protection in preventing HPV infection and cervical cancer lesions.

Recent Developments in Human Papillomavirus (HPV) Vaccinology

Human papillomavirus (HPV) is causally associated with 5% of cancers, including cancers of the cervix, penis, vulva, vagina, anus and oropharynx. The most carcinogenic HPV is HPV-16, which dominates the types causing cancer. There is also sufficient evidence that HPV types 18, 31, 33, 35, 39, 45, 51, 52, 56, 58 and 59 cause cervical cancer. The L1 protein, which, when assembled into virus-like particles, induces HPV-type-specific neutralising antibodies, forms the basis of all commercial HPV vaccines. There are six licensed prophylactic HPV vaccines: three bivalent, two quadrivalent and one nonavalent vaccine. The bivalent vaccines protect from HPV types 16 and 18, which are associated with more than 70% of cervical cancers. Prophylactic vaccination targets children before sexual debut, but there are now catch-up campaigns, which have also been shown to be beneficial in reducing HPV infection and disease. HPV vaccination of adults after treatment for cervical lesions or recurrent respiratory papillomatosis has impacted recurrence. Gender-neutral vaccination will improve herd immunity and prevent infection in men and women. HPV vaccines are immunogenic in people living with HIV, but more research is needed on the long-term impact of vaccination and to determine whether further boosters are required.