Human Papillomavirus Genotypes and HPV16 E6/E7 Variants among Patients with Genital Cancers in Vietnam.

We previously reported human papillomavirus type 52 (HPV52) as the most prevalent high-risk genotype in non-cancer individuals in Vietnam. This study aimed to evaluate HPV genotypes and HPV16 E6 and E7 (E6/E7) gene variations in Vietnamese patients with genital cancers. Biopsy samples were collected from 124 Vietnamese patients with genital cancers (20 with vaginal, 50 with vulvar, and 54 with penile cancer). The HPV-DNA was amplified and genotyped, and HPV16 E6/E7 genes were compared with those previously reported for women with normal cervical cytology (N = 23). HPV-DNA was detected in 80.6% (100/124) of the cancer patients (80.0% of vaginal, 82.0% of vulvar, and 79.6% of penile), with HPV16/18 in 86.0% (86/100) and HPV52 in 7.0% (7/100) of the HPV-positive samples. The HPV-DNA prevalence and HPV genotype distribution did not significantly differ among the genital cancer patients (both P = 0.95). Significantly fewer instances of the HPV16 A4 sublineage (34.8% vs. 82.6%, P < 0.0001) and HPV16 E7 29S (36.4% vs. 87.0%, P = 0.0002) occurred in the cancer patients than in the women with normal cytology. Our results indicate that HPV16/18 accounts for more than 85% of genital cancers in Vietnam, and the HPV16 sublineage A4 containing E7 29S may be less oncogenic.

Discrepancies in prevalence trends for HIV, hepatitis B virus, and hepatitis C virus in Haiphong, Vietnam from 2007 to 2012.

We previously reported a significant reduction in the prevalence of human immunodeficiency virus type 1 (HIV) from 2007 to 2012 in people who inject drugs (PWID; 35.9% to 18.5%, p < 0.001) and female sex workers (FSW; 23.1% to 9.8%, p < 0.05), but not in blood donors (BD) or pregnant women, in Haiphong, Vietnam. Our aim in the present study was to assess trends in the prevalence of infection with hepatitis B and C viruses (HBV and HCV, respectively). We also investigated the coinfection rates of HBV and HCV with HIV in the same groups. Between 2007 and 2012, HBV prevalence was significantly decreased in BD (18.1% vs. 9.0%, p = 0.007) and slightly decreased in FSW (11.0% vs. 3.9%, p = 0.21), but not in PWID (10.7% vs. 11.1%, p = 0.84). HCV prevalence was significantly decreased in PWID (62.1% in 2007 vs. 42.7% in 2008, p < 0.0001), but it had rebounded to 58.4% in 2012 (2008 vs. 2012, p < 0.0001). HCV prevalence also increased in FSW: 28.6% in 2007 and 2009 vs. 35.3% in 2012; however, this difference was not significant (2007 vs. 2012, p = 0.41). Rates of coinfection with HBV and HCV among HIV-infected PWID and FSW did not change significantly during the study period. Our findings suggest that the current harm reduction programs designed to prevent HIV transmission in PWID and FSW may be insufficient to prevent the transmission of hepatitis viruses, particularly HCV, in Haiphong, Vietnam. New approaches, such as the introduction of catch-up HBV vaccination to vulnerable adult populations and the introduction of HCV treatment as prevention, should be considered to reduce morbidity and mortality due to HIV and hepatitis virus coinfection in Vietnam.

Correlates of HIV Testing Among Transgender Women in Ho Chi Minh, Vietnam.

HIV prevalence among transgender women (TW) in Ho Chi Minh City is estimated at 18 %. However, no evidence-based programs or surveillance data exist in Vietnam specific to HIV testing uptake. We examined prevalence and correlates of past-year HIV testing among TW (n = 204) recruited in 2015 via snowball sampling. 59.3 % reported HIV testing in the previous year. In adjusted models, factors positively associated with HIV testing included consistent condom use during sex work with male clients; STI testing in past year; sex with casual partners in the past month; and experiences of police harassment. Factors negatively associated with recent HIV testing included daily/weekly alcohol use and post-traumatic stress symptoms. This study found significant associations between greater safety in sexual behaviors and higher rates of HIV testing. Targeted and specific services are needed for TW in Vietnam in order to address sexual risk behaviors and provide appropriate access to regular HIV testing.

Change in the Prevalence of HIV-1 and the Rate of Transmitted Drug-Resistant HIV-1 in Haiphong, Northern Vietnam.

We previously reported a significant decrease in HIV-1 prevalence, with no increase in drug-resistant HIV-1 among injecting drug users (IDU), female sex workers (FSW), and blood donors (BD), in Haiphong, Vietnam, from 2007 to 2009. In 2012, 388 IDU, 51 FSW, and 200 BD were recruited for further analysis. None had a history of antiretroviral treatment. From 2007 to 2012, HIV-1 prevalence was reduced from 35.9% to 18.6% (p<0.001), 23.1% to 9.8% (p<0.05), and 2.9% to 1% (p=0.29) in IDU, FSW, and BD, respectively. Of 79 anti-HIV-1 antibody-positive samples, 61 were successfully analyzed for the pol-reverse transcriptase (RT) region. All HIV-1 strains were CRF01_AE. Nonnucleoside RT inhibitor-resistant mutations, Y181C/I, were detected in three subjects; one had the nucleoside RT inhibitor-resistant mutations L74V and M184V and one had E138K. The prevalence of transmitted drug-resistant HIV-1 in Haiphong increased slightly from 1.8% in 2007 to 6.6% in 2012 (p=0.06).

E6 and E7 variants of human papillomavirus-16 and -52 in Japan, the Philippines, and Vietnam.

Human papillomavirus (HPV) has several intragenotypic variants with different geographical and ethnic distributions. This study aimed to elucidate the distribution patterns of E6 and E7 (E6/E7) intragenotypic variants of HPV type 16 (HPV-16), which is most common worldwide, and HPV-52, which is common in Asian countries such as Japan, the Philippines, and Vietnam. In previous studies, genomic DNA samples extracted from cervical swabs were collected from female sex workers in these three countries and found to be positive for HPV-16 or HPV-52. Samples were amplified further for their E6/E7 genes using type-specific primers and analyzed genetically. Seventy-nine HPV-16 E6/E7 genes were analyzed successfully and grouped into three lineages: European (Prototype), European (Asian), and African-2. The prevalences of HPV-16 European (Prototype)/European (Asian) lineages were 19.4%/80.6% (n = 31) in Japan, 75.0%/20.8% (n = 24) in the Philippines, and 0%/95.8% (n = 24) in Vietnam. The 109 HPV-52 E6/E7 genes analyzed successfully were grouped into four lineages, A-D; the prevalences of lineages A/B/C/D were, respectively, 5.1%/92.3%/0%/2.6% in Japan (n = 39), 34.4%/62.5%/0%/3.1% in the Philippines (n = 32), and 15.8%/73.7%/7.9%/2.6% in Vietnam (n = 38). The distribution patterns of HPV-16 and HPV-52 lineages in these countries differed significantly (P < 0.000001 and P = 0.0048, respectively). There was no significant relationship between abnormal cervical cytology and either HPV-16 E6/E7 lineages or specific amino acid mutations, such as E6 D25E, E6 L83V, and E7 N29S. Analysis of HPV-16 and HPV-52 E6/E7 genes can be a useful molecular-epidemiological tool to distinguish geographical diffusion routes of these HPV types in Asia.

Infection with high-risk HPV types among female sex workers in northern Vietnam.

Vaccines against two high-risk human papillomavirus (HPV) types, HPV-16, and HPV-18, are in use currently, with high efficacy for preventing infections with these HPV types and consequent cervical cancers. However, circulating HPV types can vary with geography and ethnicity. The aim of this study was to investigate the prevalence of HPV types and the association between HPV types and abnormal cervical cytology among female sex workers in Northern Vietnam. Cervical swabs and plasma samples were collected from 281 female sex workers at two health centers in Hanoi and Hai Phong in 2009. The HPV L1 gene was amplified by PCR using original and modified GP5(+)/6(+) primers. Amplified PCR products were genotyped by the microarray system GeneSquare (KURABO) and/or clonal sequencing. Of the 281 women, 139 (49.5%) were positive for HPV DNA. Among the HPV-positive samples, 339 strains and 29 different types were identified. Multiple-type and high risk-type HPV infections were found in 85 (61.2%) and 124 (89.2%) women, respectively. The most common genotype was HPV-52, followed by HPV-16, HPV-18, and HPV-58. Abnormal cervical cytology was detected in 3.2% (9/281) of the women, and all of these samples were positive for HPV-DNA. Age ≤25 years and infection with human immunodeficiency virus were associated positively with HPV infection among the women while ever smoking was associated negatively. These results show that HPV-52 is most prevalent among female sex workers in Northern Vietnam, most of whom had normal cervical cytology. This information may be important for designing vaccination strategies in Vietnam.

No increase of drug-resistant HIV type 1 prevalence among drug-naive individuals in Northern Vietnam.

We reported previously that the prevalence of drug-resistant HIV-1 among antiretroviral therapy (ART)-naive individuals in Northern Vietnam was 2.9% in 2007 and 6.2% in 2008. To investigate the continuing trend of prevalence, we collected plasma samples from 958 individuals in Hai Phong and Hanoi in 2009, extracted viral RNA from HIV-1 antibody-positive samples, and analyzed them genetically. HIV-1 antibody prevalence was 26.8% in injecting drug users (n=302), 13.4% in female sex workers (n=284), 0.5% in blood donors (n=206), and 0.6% in pregnant women (n=166). All HIV-1 strains were CRF01_AE. Nonnucleoside reverse-transcriptase inhibitor resistance mutations were found in two (2.0%) of the 102 successfully analyzed cases (one case with the Y181C and one with the K101E). No nucleoside reverse-transcriptase inhibitor resistance or protease inhibitor resistance mutations were detected. The prevalence of circulating ART-resistant HIV-1 in Northern Vietnam did not increase from 2007 to 2009, although the rate of ART coverage did increase.

Prevalence of HBV infection among different HIV-risk groups in Hai Phong, Vietnam.

Hepatitis B virus (HBV) infection in Hai Phong, northern Vietnam, was characterized by analyzing the prevalence and genotype distribution of HBV as well as co-infection with human immunodeficiency virus type 1 (HIV-1) among five different risk groups for HIV infection. Plasma samples were collected from intravenous drug users (n=760, anti-HIV-1 antibody positive rate: 35.9%), female sex workers (FSWs; n=91, 23.1%), seafarers (n=94, 0%), pregnant women (n=200, 0.5%), and blood donors (n=210, 2.9%) in 2007 [Ishizaki et al. (2009): AIDS Res Hum Retroviruses 25:175-182]. Samples were screened for the hepatitis B surface antigen (HBsAg) and anti-HBs antibody and analyzed genetically. The cumulative HBV incidence rate (HBsAg+anti-HBs) was 53.2% (10.7+42.5%) in intravenous drug users, 51.6% (11.0+40.6%) in FSWs, 54.3% (9.6+44.7%) in seafarers, 50.5% (12.5+38.0%) in pregnant women, and 51.0% (18.1+32.9%) in blood donors; there was no significant difference among these groups. Of 163 HBsAg-positive samples, 113 could be analyzed genetically. Phylogenetic analysis, based on the preS1 region, revealed genotype B4 was most prevalent (90/113; 79.6%), followed by C1 (17.7%), I1 (1.8%), and B2 (0.9%). There was no significant difference in HBV genotype distribution among different HIV infection-risk groups. The prevalence of HBsAg was 10.3% (31/301) in HIV-1-infected individuals and 12.5% (132/1,054) in non-HIV-1-infected individuals, which was not significant. In addition, no significant difference in HBV genotype distribution was observed between HBV/HIV-1 coinfected and HBV mono-infected groups. These results suggest that, although HBV and HIV-1 share modes of transmission, major transmission routes of HBV have been different from those of HIV-1 in Hai Phong, Vietnam.