title: Prevalence of human papillomavirus types in cervical cancerous and precancerous lesions of Ecuadorian women.
abstract: Human Papillomavirus (HPV) is the most common sexually transmitted infection worldwide and it is responsible for most cases of uterine cancer. In Ecuador there is limited information about HPV types (and variants) in cancerous lesions; however, identifying the type-specific HPV prevalence in cervical lesions of women living in Ecuador is important to better predict the impact of HPV prophylactic vaccination in this country. We studied the prevalence of HPV types in cervical cancerous or precancerous lesions from 164 Ecuadorian women and found that 86.0% were HPV positive. The most common types were HPV16 (41.8%) and HPV58 (30.5%). Interestingly, HPV18 was detected only in 2.8% of the HPV-positive samples. Fifteen DNA sequences (genes E6 and L1) from 16 samples positive for HPV16 belonged to the European lineage, considered one of the least carcinogenic lineages, and 1 (6.25%) to the Asian-American lineage. Similar analysis in 12 HPV58 positive samples showed that 10 (83.3%) sequences grouped in sublineage A2, which belongs to the oldest HPV58 lineage, 1 belonged to A3 and 1 to lineage C. This study suggests that the currently used HPV vaccines (bivalent and tetravalent) may have lower effectiveness in Ecuador than in other geographic locations where HPV18 is more prevalent.
authors.affiliation: Instituto de Microbiología, Universidad San Francisco de Quito, Quito, Ecuador.
authors.forename: Lorena
authors.initials: L
authors.lastname: Mejía
authors.affiliation: Instituto de Microbiología, Universidad San Francisco de Quito, Quito, Ecuador.
authors.forename: Diana
authors.initials: D
authors.lastname: Muñoz
authors.affiliation: Instituto de Microbiología, Universidad San Francisco de Quito, Quito, Ecuador.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Trueba
authors.affiliation: Unidad de Ginecología y Colposcopía, Hospital SOLCA, Quito, Ecuador.
authors.forename: Leopoldo
authors.initials: L
authors.lastname: Tinoco
authors.affiliation: Instituto de Microbiología, Universidad San Francisco de Quito, Quito, Ecuador.
authors.forename: Sonia
authors.initials: S
authors.lastname: Zapata
mesh_terms: D000328:Adult; D000368:Aged; D004484:Ecuador / Q000453:epidemiology; D005260:Female; D005838:Genotype; D006801:Humans; D008875:Middle Aged; D027383:Papillomaviridae / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D030361:Papillomavirus Infections / Q000150:complications / Q000453:epidemiology* / Q000821:virology*; D010802:Phylogeny; D011230:Precancerous Conditions / Q000453:epidemiology / Q000821:virology*; D015995:Prevalence; D017422:Sequence Analysis, DNA; D002583:Uterine Cervical Neoplasms / Q000453:epidemiology / Q000821:virology*
keywords: Ecuador; HPV16 variants; HPV58 variants; cervical cancer