PCR-RFLP-Detected Human Papilloma Virus Infection in a Group of Senegalese Women Attending an STD Clinic and Identification of a New HPV-68 Subtype

Abstract

Cancer of the cervix is the most common malignant tumor among women in Africa and, in particular, Senegal. Studies of the prevalence of human papilloma virus (HPV) infection in Africa have mainly focused on carcinomas. Data on the presence of the virus in women with normal cervical cytology are scarce. In this study, 158 cytologically normal women who had been referred to the ‘Institut Pasteur de Dakar’ (Senegal) for various genital complaints were investigated for the presence of HPV on exfoliated cells by PCR-RFLP. HPV was detected in 13.9% of cases. Oncogenic type HPV 16 was the most common type (40.9%), followed by HPV 53 and HPV 58, both detected in 13.6% of cases. Mixed HPV infections were present in 13.6% of the subjects. Only HPVs belonging to the intermediate-high risk group were detected. These data suggest the need for careful cytological control of patients. A PCR-HPV fragment (GA115) possessing an original RFLP pattern was isolated. After sequencing, it showed a nucleotide homology of 97.1% with HPV 68 and should therefore be considered a new HPV 68 subtype. The use of PCR-RFLP strategy enables detection and typing of all known and as yet unknown genital HPVs. Variant and subtype classification of HPV types identified by oligonucleotide probe methods may need to be refined, especially for less prevalent HPVs and in areas where little information on HPV prevalence is available. More studies are needed to characterize satisfactorily the epidemiology of HPV in Africa.

Cervical human papillomavirus infection and squamous intraepithelial lesions in rural Gambia, West Africa: viral sequence analysis and epidemiology

“…The DNA sequences of HPV-16, -18, -33 and -68 revealed HPV variants found by other African studies. In particular, the Gambian HPV-68 samples are an exact DNA match to an HPV-68 subtype first isolated from a study in neighbouring Senegal (Astori et al, 1999). Our study also confirms the importance of HPV-16 Af1, the most prevalent of the HPV-16 subtypes in Africa (Yamada et al, 1997).…”

“…The high cervical HPV infection prevalence and SIL are in agreement with Gambian Cancer Registry data (Koulibaly et al, 1997;Bah et al, 2001). Comparable prevalences of 14% have been observed in two cytologically normal populations in Senegal, the only nation on which The Gambia borders (Astori et al, 1999;Xi et al, 2003). A recent study from Nigeria, West Africa, of an unselected population of similar size typed by GP5 þ / 6 þ PCR-ELISA, found an HPV prevalence of 26% (Thomas et al, 2004).…”

“…Three selective urban Senegalese studies found a very low prevalence of HPV-35 ranging from no HPV-35 positive samples (Astori et al, 1999;Chabaud et al, 1996) to 1% in the most recent (Xi et al, 2003). Inconsistency between studies examining Senegal and Gambian populations with overlapping ethnic groups, religious practices and trade routes initially appears incongruous.…”

Genotypes of human papilloma virus in Sudanese women with cervical pathology

“…Many sexually active populations in many parts of the world have been infected with HPV during their lifetime [2], most HPV-infected individuals eliminate the virus without developing clinical symptoms [3]. Nearly 100 HPV types have been molecularly identified and about 40 of these can infect the ano-genital tract [4].…”

“…Thus, the prevalence of HPV in a population of people is invariably greater than the number of women who develop cervical lesions. HPV type distribution and cervical cancer has been studied in other African countries [3,9]. However, there is as yet no published data from The Sudan.…”