Molecular-Epidemiological Study for 19 High and Medium-Risk HPV types in Bulgarian Patients

Cervical cancer ranks as the 4th leading cause of female cancer and cancer deaths in the world. More than 99% of cervical cancer cases are due to HPV infection. Vaccination can significantly reduce the number of HPV-related cancers in the future. The next big step is to change the order of the tests, ie. cervical cells are first tested for HPV, and then analyzed under a microscope. The objective of our study was to define the incidence of 19 types of HPV in Bulgarian women attended for routine gynecologic examination, in order to obtain the molecular-epidemiological spectrum of this infection in the context of the actual preventive programs. We have used the medium-high risk PapillomaStrip kit, based on the principle of reverse hybridization, in samples of 151 Bulgarian women. We detected the total frequency of 44.4% for HPV infection and higher frequency in younger age group ( 40 years old women (28%). The most frequent HPV types from our study were HPV 45 and 52 (10.6%), HPV 66 (8.6%) and HPV 31 (8%). In PAPI/II it was HPV52 (11.3%), followed by HPV45 (10.5%) and HPV66 (8.3%). In PAPIII the most common was HPV16 (44.4%), followed by HPV 45, 31, 66 and 59 (each of 22.2%). We emphasized on the high frequency of HPV45 in our study, which is reported as one of the most frequent types in cervical cancer. In conclusion, HPV genotyping provides information on the carriage of high-risk types and increased attention to these patients. This is a valuable information for planning preventive programs in regard to choosing diagnostic tests and vaccination. Our results revealed the wide spectrum of HPV infection in Bulgarian women, as about 70% of infected patients carry high-risk HPV 45, 52, 31, 16 and 18.