Investigator

Cathy Visser

University Of Pretoria

CVCathy Visser
Papers(2)
Aptima HPV E6/E7 mRNA…Combining cervical ca…
Collaborators(6)
Frederick Haynes Van …Greta DreyerJustin HarveyKarin Louise RichterLeon Cornelius SnymanMatthys H. Botha
Institutions(3)
University Of PretoriaStellenbosch Universi…Tygerberg Hospital

Papers

Aptima HPV E6/E7 mRNA and cytology cross-sectional performance as primary screening tests for detection of high-grade cervical lesions in HIV positive and negative women in South Africa

Objective To assess the performance of APTIMA ® HPV E6/E7 mRNA assay (AHPV) with HPV 16 and 18/45 genotyping (AHPV-GT) and cytology in detecting cervical cancer and precancer in HIV positive and negative women in South Africa. Methods A multicentre cross-sectional study was performed in women aged 25–64 (n = 992) with cytology and AHPV with AHPV-GT reflex testing. All screen-positive and a random subset of screen-negative women were referred for colposcopy and biopsy. Results On cytology, low-grade squamous intraepithelial lesion (LSIL) or higher was found in 9.7% of HIV negative and 35.8% of HIV positive women. HPV mRNA positivity was 19.5% (4.4% HPV 16, 2.8% HPV 18/45, and 6.9% other high-risk HPV) in HIV negative women, compared to 45.8% (9.4% HPV 16, 9.7% HPV 18/45, and 27.6% other high-risk HPV) in HIV positive women . The prevalence of histological abnormalities in HIV negative vs HIV positive women was 24.3 vs 46.0% for cervical intraepithelial neoplasia (CIN) 2+, 10.2 vs 24.1% for CIN3+, and 1.4 vs 2.4% for invasive squamous cell carcinoma. AHPV sensitivity for detection of CIN3 + performed the best: 69.0% (95% confidence interval (CI) 56.8–81.1) in HIV negative vs 81.4% (95% CI 73.7–89.0) in HIV positive women, followed by ASCUS + (atypical squamous cells of undetermined significance) cytology: 58.6% (95% CI 45.7–71.6) vs 76.5% (95% CI 68.1–84.8). The best positive predictive value for CIN2 + was for AHPV-GT16, followed by AHPV-GT16,18/45 and cytology LSIL+: HIV-negative women 84.0% (95% CI 68.9–99.1); 76.9% (95% CI 63.3–90.6); 75.0% (95 CI% 61.2–88.9) and HIV-positive women 92.5% (95% CI 84.1–100); 86.8% (95% CI 79.1–94.6); 84.0% (95% CI 77.6–90.3). Conclusion Significantly more HPV infection and cytological/histological abnormalities and advanced disease were seen in HIV positive women. The lower than expected clinical sensitivities of all screening tests are comparable to HPV DNA sensitivities reported in similar populations. AHPV with AHPV-GT performed better than cytology as a screening and triage test.

Combining cervical cancer screening for mothers with schoolgirl vaccination during human papillomavirus (HPV) vaccine implementation in South Africa: results from the VACCS1 and VACCS2 trials

The platform provided by human papillomavirus (HPV) vaccination for linked public health interventions to improve cervical cancer prevention remains incompletely explored. The Vaccine And Cervical Cancer Screen (VACCS) cross-sectional observation trials aimed to evaluate the efficacy of school-based HPV vaccination linked with maternal cervical cancer screening. Girls from 29 schools in two provinces in South Africa were invited in writing to receive HPV vaccination. Two approaches to informed consent were compared, namely an audiovisual presentation (VACCS1) and in written format (VACCS2). Markers of vaccine uptake and coverage were calculated, namely uptake among the invited and consented cohorts, and rates of completion and sufficient vaccination. Mothers and female guardians received educational material about cervical cancer, and either a self-sampling device or an invitation to attend existing screening facilities. Knowledge was assessed via structured questionnaires (before and after), and screening uptake was self-reported and directly assessed and compared between these approaches. Vaccine acceptance among 5137 invited girls was similar for the two methods of consent; 99.3% of consented girls received a first dose; overall completion rate was 90.5%. More girls were vaccinated using a two-dose (974/1016 (95.9%)) than a three-dose regimen (1859/2030 (91.6%)). The questionnaire (n=906) showed poor maternal knowledge which improved significantly (p<0.05) after health education; only 54% of mothers reported any previous screening. The offer of a self-sampling device (n=2247) was accepted by 43.9% of mothers, but only 26% of those invited to screen at existing facilities (n=396) reported subsequent screening. Successful linking of primary health interventions to control cervical cancer was demonstrated. School-based HPV vaccination, linked to health education, self-sampling, and molecular screening resulted in significant improvements in knowledge and screening.

2Papers
6Collaborators