High prevalence of HPV 18 and multiple infections with oncogenic HPV genotypes in women at risk of cervical cancer examined in Manaus, Brazil

ABSTRACT

Cervical cancer is a serious public health problem in Brazil, especially in Manaus (Amazonas), the city with the highest incidence rate of cervical cancer in the country. Persistent infection with oncogenic human papillomavirus (HPV) genotypes is the cause of disease development. The aim of this study was to investigate the prevalence of oncogenic genotypes in women at high risk for cervical precancer examined in two policlinics in Manaus. One hundred and two patients who underwent colposcopy took part in the research. The DNA samples obtained from the cervical epithelium were analyzed by PCR with type-specific primers for the detection of eight oncogenic genotypes, which were chosen based on previous studies. The presence of HPV virus was detected in all samples. The most prevalent oncogenic genotypes were 18 (47.1%) and 16 (45.1%). Interestingly, HPV 18 was considered uncommon in this region. In addition to these, genotypes 31 (19.6%), 58 (19.6%), 33 (18.6%), and 45 (15.7%) also had a relatively high frequency in this population. Fifty-six women (54.9%) had multiple infections with up to five oncogenic types. Also, the presence of genotypes other than 16 and 18 was observed in most samples (57.8%), which also deserves attention since they are not covered by currently available vaccines against HPV in Brazil. The high prevalence and multiple infections with several oncogenic HPV genotypes in association with precursor lesions for cervical cancer highlighted the need to improve strategies to prevent this disease in Amazonas.