Journal of Medical Virology 81:545–551 (2009) High-Risk HPV Types in Lesions of the Uterine Cervix of Female Commercial Sex Workers in the Philippines Michiko Miyashita, 1 Dorothy M. Agdamag, 2 Toshiyuki Sasagawa, 3 Kaori Matsushita, 1 Lourdes Ma. Salud, 4 Calixto O. Salud, 4 Kunikazu Saikawa, 5 Prisca S. Leano, 2 Teresita Pagcaliwagan, 4 Jessica Acuna, 4 Azumi Ishizaki, 1 Seiji Kageyama, 1 and Hiroshi Ichimura 1 * 1 Department of Viral Infection and International Health, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan 2 STD AIDS Cooperative Central Laboratory, San Lazaro Hospital, Manila, Philippines 3 Graduate School of Health Science, Kanazawa University, Kanazawa, Japan 4 Makati Social Hygiene Clinic, Manila, Philippines 5 Department of Human Pathology, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan In order to prevent cervical cancer, vaccines against human papilloma virus types 16 (HPV-16) and 18 (HPV-18) have been implemented world- wide. However, the HPV types that cause cancer can differ according to geographical area and ethnicity. In this new era of the HPV vaccine, it is important to elucidate the prevalent HPV types in each area. Therefore, the prevalence of HPV infection and cervical abnormalities among 369 female commercial sex workers in the Philippines were examined. HPV L1 gene was amplified by polymerase chain reaction (PCR) using modified GP5þ/6þ primers, and genotyping was per- formed by sequencing cloned PCR products. HPV DNA was detected in 211 (57.2%) women, among whom 46 HPV types were identified. HPV- 52 was most common and multiple-type infection was observed in 44.5%. Among 56 women with abnormal cervical cytology (low- and high-grade squamous intraepithelial lesions and adeno- carcinoma in situ), HPV-52 was most common (23.2%), followed by HPV-16 (19.6%), -58 (10.7%), and -67 (10.7%). Only 27% of these women were positive for HPV-16 and -18. Multivariate analysis revealed that HPV-16, -39, -52, -67, and -82 were significantly associated with abnormal cytology. Repeated analysis of HPV-52 single-positive samples using the original GP5þ/6þ PCR primers produced negative results in 57% of cases, suggesting that the prevalence of HPV-52 infec- tion may have been underestimated in previous studies, and the current vaccines may not be sufficient for preventing infection and the devel- opment of premalignant lesions of the cervix in women in the Philippines. J. Med. Virol. 81:545–551, 2009. ß 2009 Wiley-Liss, Inc. KEY WORDS: HPV high-risk type; cervical cytology; Philippines; female commercial sex workers INTRODUCTION Human papillomavirus (HPV) is the most important risk factor for cervical cancer [Mun ˜ oz et al., 2003], which is the second most common malignancy and the third most common cause of cancer-related death in women [Parkin et al., 2005]. The incidence and mortality of cervical cancer are very high in women of reproductive age, especially in developing countries [Parkin et al., 2005; Frain et al., 2006]. Cervical cancer screening using cytological testing and HPV vaccination are paramount for preventing cervical cancer in young women. More than 40 HPV types have been identified in the mucosal epithelia of the human genital tract; these are classified into high-risk and low-risk types according to their ability to cause cancer [Mun ˜ oz et al., 2003]. HPV type 16 (HPV-16) is the most common high-risk type and is detected in 50–60% of high-grade squamous Grant sponsor: Ministry of Health, Labor, and Welfare (International Health Cooperation Research); Grant number: 19C-4. *Correspondence to: Hiroshi Ichimura, MD, PhD, Department of Viral Infection and International Health, Graduate School of Medical Science, Kanazawa University, 13-1 Takaramachi, Kanazawa 920-8640, Japan. E-mail: ichimura@med.kanazawa-u.ac.jp Accepted 4 November 2008 DOI 10.1002/jmv.21416 Published online in Wiley InterScience (www.interscience.wiley.com) ß 2009 WILEY-LISS, INC.