The 2010 global proficiency study of Human Papillomavirus genotyping in vaccinology.

Accurate and internationally comparable Human Papillomavirus (HPV) DNA genotyping is essential both for evaluation of HPV vaccines and for effective monitoring and implementation of vaccination programs. World Health Organisation (WHO) HPV Laboratory Network (LabNet) regularly issues international proficiency studies. The 2010 HPV genotyping proficiency panel for HPV vaccinology contained 43 coded samples composed of purified plasmids of sixteen HPV types (HPV 6, 11, 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68a and 68b) and 3 coded extraction controls. Proficient typing was defined as detection in both single and multiple infections of 50 International Units (IU) of HPV 16 and HPV 18 DNA and 500 genome equivalents (GE) for the other 14 HPV types. Ninety-eight laboratories worldwide submitted a total of 132 datasets. Twenty-four different HPV genotyping assay methods were used, with Linear Array being most commonly used. Other major assays used were Lineblot/Inno-LiPa, CLART, type-specific real-time PCR, PCR-Luminex and different microarray assays. Altogether 72 data sets were proficient for detection of more than one type, only 26 data sets proficiently detected all sixteen HPV types. The major oncogenic HPV types, 16 and 18, were proficiently detected in 95.0% (114/120) and 87.0% (94/108) of datasets, respectively. Forty-six datasets reported multiple false positive results and were considered non-proficient. A trend towards increased sensitivity of assays was seen for the 41 laboratories that participated in both 2008 and 2010. In conclusion, continued global proficiency studies will be required for establishing comparable and reliable HPV genotyping services for vaccinology worldwide.