Official figures suggest the change from Pap smear tests to human papillomavirus (HPV) testing has been effective.

In 2017, the National Cervical Screening Program switched from biennial cytological Pap testing of asymptomatic women aged 18–69 years, to 5-yearly primary HPV testing of women aged 25–74 years.

It has been a “major paradigm shift” according researchers led by Dr Dorothy Machalek from the Centre for Women’s Infectious Diseases at Melbourne’s Royal Women’s Hospital.

A retrospective review of 195,606 specimens submitted for HPV testing between December 2017 and 31 May 2018, found oncogenic HPV was detected in 8.1 per cent of screening tests and 20.9 per cent of non-screening tests.

Among oncogenic HPV-positive screening tests from women of recommended screening age (25–74 years), 35.5 per cent also had a cytologic abnormality.

The proportion of HPV16/18-positive samples with high-grade abnormality was 15.3 per cent. For samples positive for other oncogenic HPV types, the proportion was 6.3 per cent. Repeat HPV testing after 12 months was recommended for 5.4 per cent and direct colposcopy for 2.6 per cent of screened women aged 25–74 years.

“A key finding was that the rate of referral to colposcopy based on HPV primary screening sample results for women of recommended screening age (2.6 per cent) was considerably higher than that based on historical primary cytology screening results from our laboratory (0.8 per cent),” Prof Machalek and colleagues wrote.

“The higher rate is broadly consistent with clinical trial data and predictions from modelling.

“The switch from cytology- to primary HPV-based screening in Australia will ensure cervical screening is evidence-based and best practice,” they concluded.

“While the predicted long-term benefits are substantial, timely monitoring of the transitional phase is critical for ensuring the program performs as expected and community confidence in the policy is maintained.”

The full study is accessible here.