Prevalence of cervical human papillomavirus (HPV) infection in Vanuatu.

To provide information on human papillomavirus (HPV) prevalence and the distribution of individual HPV types in Pacific Islands, we conducted a population-based survey in Vanuatu, South Pacific. Nine hundred and eighty-seven women between 18 and 64 years of age were included. GP5(+)/6(+)-mediated PCR assay was used for HPV testing. The prevalence of 44 HPV types was 28.4% corresponding to an age (world)-standardized prevalence of 25.0% [95% confidence interval (CI), 21.9%-28.0%]. The prevalence of high-risk (HR) HPV types was 21.7% (age-standardized prevalence of 19.2%; 95% CI, 16.4%-22.0%). Among 840 women with adequate cytologic results, 13.6% showed cervical abnormalities, including 3.6% with high-grade squamous intraepithelial lesions (HSIL) and 0.8% with invasive cervical carcinoma. HPV prevalence declined from 46.1% in women aged ≤21 to 15.3% in those ≥45 years. Being single was significantly associated with HPV positivity. HR HPV findings by PCR assay and hybrid capture 2 (HC2; conducted in Vanuatu) were moderately correlated (κ test = 0.59). The positive predictive values of HR HPV positivity for HSIL or worse were 27.6% for PCR and 35.2% for HC2 among women aged ≥30. Nearly half of screening-positive women could not be reevaluated mainly on account of the difficulty to trace back women. The availability of a rapid HPV testing method that allows see-and-treat approaches at the same visit would be, therefore, essential. On account of their high cumulative burden of cervical lesions, also women older than 40 years should be included in at least the first screening round in unscreened populations.

Evaluation of a cervical cancer screening program based on HPV testing and LLETZ excision in a low resource setting.

We conducted studies in Vanuatu to evaluate potential screening and treatment strategies to assist with control of cervical cancer. In a pilot study of 496 women, visual inspection and cytology were evaluated as screening tests for detection of CIN 2 or worse (CIN2+), observed in 21 of 206 subjects biopsied on the basis of abnormal visual inspection or cytology. Sensitivity of visual inspection with Lugol's Iodine for detection of CIN2+ on biopsy was 0.63, specificity was 0.32, and the positive predictive value was 0.09. For HSIL cytology, sensitivity was 0.99, specificity was 0.77, and the positive predictive value was 0.88. HSIL cytology was significantly more sensitive and had a significantly higher PPV for CIN 2+ than visual inspection (p<0.01). In a further study of 514 women, we compared testing for HR HPV and cytology as predictors of biopsy proven CIN 2+. Sensitivity of HSIL cytology for CIN2+ as established by loop excision of the cervix was 0.81, specificity was 0.94, and positive predictive value was 0.48. Sensitivity of a positive test for HR HPV for detection of CIN2+ was non-significantly different from cytology at 0.81, specificity was 0.94, and positive predictive value was 0.42. Combining the two tests gave a significantly lower sensitivity of 0.63, a specificity of 0.98, and a positive predictive value of 0.68. For women over 30 in a low resource setting without access to cytology, a single locally conducted test for high risk HPV with effective intervention could reduce cervical cancer risk as effectively as intervention based on cytology conducted in an accredited laboratory.