Molecular analysis of human Papillomavirus detected among women positive for cervical lesions by visual inspection with acetic acid/Lugol's iodine (VIA/VILI) in Libreville, Gabon.
BACKGROUND
The human papillomavirus (HPV) is the causative agent of cervical cancer, which is the leading cancer-related cause of death for women in Sub-Saharan Africa. In 2013, the Gabonese Ministry of Health and the Sylvia Bongo Ondimba Foundation implemented cervical cancer screening programs based on the detection of cancerous lesions by visual inspection with acetic acid and/or Lugol's iodine (VIA/VILI). This pilot study was set up to determine the HPV profile and analyze the nucleotide sequence variation of HPV16 circulating in patients with cervical abnormalities detected by VIA/VILI testing.


METHODS
The cervical abnormalities observed upon VIA/VILI were confirmed by liquid-based cytology for all tested women. Nested PCR using the MY09/11 and GP5+/6+ primer sets was used to detect HPVs present in the extracted DNA. HPV genotypes were determined after sequencing of amplicons based on a high-throughput sequencing approach. For isolates of the HPV16 genotype, the E6 gene and the long control region (LCR) were directly sequenced using Sanger method.


RESULTS
The study included 87 women who showed a positive VIA/VILI result. Cervical abnormalities were found in 40.23 % of women and 40 % were classified as high-grade lesions. The HPV detection rate was 82.9 % among women with abnormal cytology. Among all the identified high-risk HPV genotypes, HPV16, 18 and 33 were the most frequent. Multiple HPV infections were observed in 42.31 % of HPV-infected women. Analysis of the HPV16 sequence variation in the E6 gene and in the LCR showed that 85.3 and 14.7 % belonged to the African and European lineages, respectively. Among the African branch variants, Af2 was the most frequently identified in this study.


CONCLUSIONS
This study offers the first report of the HPV detection rate and molecular epidemiology among Gabonese women with a positive result in a VIA/VILI screening test. Moreover, data on the HPV16 sequence variation confirm the predominance of African variants in high-grade lesions.
Department of Zoonosis and Emerging Diseases, Centre International de Recherches Médicales de Franceville (CIRMF), Franceville, BP 769 Gabon.
Pamela Boundzanga
PB
Moussavou
Institut de Cancérologie de Libreville (ICL), Libreville, Gabon.
Ismaël Hervé
IH
Koumakpayi
Department of Zoonosis and Emerging Diseases, Centre International de Recherches Médicales de Franceville (CIRMF), Franceville, BP 769 Gabon.
Andriniaina Andy
AA
Nkili-Meyong
Department of Zoonosis and Emerging Diseases, Centre International de Recherches Médicales de Franceville (CIRMF), Franceville, BP 769 Gabon.
Ingrid
I
Labouba
Institut de Cancérologie de Libreville (ICL), Libreville, Gabon.
Ulrich
U
Bisvigou
Institut de Cancérologie de Libreville (ICL), Libreville, Gabon.
Junie K
JK
Chansi
Institut de Cancérologie de Libreville (ICL), Libreville, Gabon.
Corinne
C
Engohan-Aloghe
Centre Hospitalier Universitaire de Libreville (CHUL), Service de gynécologie obstétrique, Libreville, Gabon.
Frederic
F
Dissanami
Centre Hospitalier Universitaire de Libreville (CHUL), Service de gynécologie obstétrique, Libreville, Gabon.
Nathalie
N
Ambounda
Institut Pasteur, Unité Environnement et risques infectieux, Cellule d'Intervention Biologique d'Urgence, Paris, France.
Anne-Sophie
AS
Delannoy-Vieillard
Institut Pasteur, Unité Environnement et risques infectieux, Cellule d'Intervention Biologique d'Urgence, Paris, France.
Laure
L
Diancourt
Department of Zoonosis and Emerging Diseases, Centre International de Recherches Médicales de Franceville (CIRMF), Franceville, BP 769 Gabon ; Ministère de la Santé, Direction général de la Santé, Libreville, Gabon.
Dieudonne
D
Nkoghe
Department of Zoonosis and Emerging Diseases, Centre International de Recherches Médicales de Franceville (CIRMF), Franceville, BP 769 Gabon ; Institut de Recherches et de Développement (IRD), Maladies Infectieuses et vecteurs: Ecologie, génétique, Evolution et Contrôle (IRD 224 - CNRS 5290 6 UM1- UM2), Montpellier, France.
Eric M
EM
Leroy
Institut de Cancérologie de Libreville (ICL), Libreville, Gabon.
Ernest
E
Belembaogo
Department of Zoonosis and Emerging Diseases, Centre International de Recherches Médicales de Franceville (CIRMF), Franceville, BP 769 Gabon ; Centre National de la Recherche Scientifique, UMR3569, Paris, France.
Nicolas
N
Berthet
Detection rate; Gabon; Human papillomavirus; Molecular variant; Visual inspection