HIV-1 CRF07_BC infections, injecting drug users, Taiwan

Forty years of HIV infection and AIDS in Taiwan: Reflection on the past and looking toward the future

We review the epidemiology, policies, and control programs of HIV infection in Taiwan in the past 40 years since the first case of HIV infection was diagnosed in 1984. With the introduction of combination antiretroviral therapy (ART) in Taiwan in 1997, the incidences of HIV-related opportunistic illnesses and mortality have significantly declined. However, despite improved access to HIV testing and treatment, late presentation of HIV infection remains common. Unprotected sex, particularly among men who have sex with men, continues to be the leading risk for HIV transmission after implementation of harm reduction program to control an outbreak of HIV infection among people who inject drugs that occurred in 2003-2007. The sequential introduction of well-tolerated, effective, single-tablet antiretroviral regimens has facilitated the implementation of "treat-all" policy in 2016, rapid ART initiation within 7 days of diagnosis in 2018, and same-day ART initiation in 2021 when immunochromatography was used for rapid confirmation of HIV infection. Government-funded pilot program of pre-exposure prophylaxis for HIV infection, which was launched in 2016 followed by wider enrollment of people at high risk for HIV acquisition in 2018, have contributed to sustained declines of the incidence of HIV infection since 2018, along with high rates of linkage to HIV care, ART initiation, viral suppression, and retention in care in Taiwan. Challenges remain to achieve HIV elimination and long-term successful management of HIV infection, which include stigma and discrimination, late presentation of HIV infection, and accelerated ageing with increasing rates of co-morbidities among people with HIV.

Genetic history of hepatitis C virus genotype 6 in Taiwan

Unlike hepatitis C virus (HCV) genotype (GT) 6, which is widely circulated in Southeast Asia and South China, GT 6 was not reported in Taiwan until 2006. GT 1b and 2a, also known as global HCV subtypes, have been reported as major GTs circulating in Taiwan. Because of improvement in genotyping kits and sequencing techniques for the subtyping of HCV, an increasing number of GT 6 subtypes have been reported, especially subtype 6a among intravenous drug users with human immunodeficiency virus infection after an outbreak since 2003. Thus, HCV GT 6 infection is regarded to be closely associated with injection drug use. However, recently, we found an unexpectedly high GT 6 prevalence in the general population in Tainan, southern Taiwan. Most of these GT 6 samples belonged to a putative novel subtype closely related to 6g and 6w instead of 6a. Phylogenetic analyses indicated that this putative 6g-related novel subtype and 6w could be indigenous in southern Taiwan for centuries. Southern Taiwan could be the origin of HCV subtype 6w. This finding might change the perspective of HCV epidemiology in Taiwan.

Hepatitis C Virus Subtypes Novel 6g-Related Subtype and 6w Could Be Indigenous in Southern Taiwan with Characteristic Geographic Distribution

Hepatitis C virus (HCV) genotype (GT) 6 is the most genetically diverse GT and mainly distributed in Southeast Asia and south China but not Taiwan. Earlier studies showed the major HCV GTs in Taiwan were GT 1b and 2 with very rare GT 6 except in injection drug users (IDUs), and subtype 6a is the main GT 6 subtype among IDUs. Recently, we reported a much higher prevalence (18.3%) of GT 6 in Tainan City, southern Taiwan. This study was designed to clarify the subtypes of GT 6 in this endemic area. A total of 3022 (1343 men and 1679 women) HCV viremic patients were enrolled. Subtypes of GT 6 were determined by sequencing of core/E1 and nonstructural protein 5B in 322 of 518 GT 6 patients. The overall GT 6 prevalence rate was 17.1% (518/3022), with higher prevalence districts (>25%) located in northern Tainan. A novel 6g-related subtype is the most prevalent subtype (81.0%), followed by 6w (10.8%), 6a (7.5%), and 6n (0.7%). The high GT 6 prevalence in Tainan was mainly due to a novel 6g-related subtype and 6w. These two subtypes could be indigenous in Tainan with characteristic geographic distribution.

Non-opioid recreational drug use and a prolonged HIV outbreak among men who have sex with men in Taiwan: An incident case-control study, 2006-2015

BACKGROUND/PURPOSE

Limited data are available on the role of illicit non-injecting drug use in a prolonged HIV outbreak that predominantly affected men who have sex with men (MSM) in Taiwan since 2006. We aimed to assess associations between specific types of drug use and incident HIV infections in this outbreak.

METHODS

We conducted a retrospective case-control study among MSM clients at voluntary counselling and testing (VCT) service at National Taiwan University Hospital (Taipei, Taiwan). We used BED IgG-capture enzyme immunoassay to identify incident HIV infection (cases), individually matched to HIV-negative MSM clients (controls) by HIV testing date. We used a structured questionnaire to obtain the information on illicit drug use and sexual risk behaviors.

RESULTS

From a total of 15,305 MSM client visits during 2006-2015, 387 cases were matched to 1012 controls. Use of inhaled nitrites (adjusted odds ratio [aOR] 2.1), MDMA (aOR 2.9), amphetamines (aOR 1.6), and ketamine (aOR 1.5) were independently associated with incident HIV infection. Polydrug (≥2 drugs) use was associated with the highest risk (aOR 4.3; 95% CI 2.6-7.2). While the proportion of MSM VCT clients who reported use of any recreational drug remained stable during 2006-2015 (average: 9.7%, P: 0.38), there was a shift in specific types of drug use, from MDMA/ketamine to inhaled nitrites/amphetamine, after 2011 (all Ps < 0.05).

CONCLUSION

Non-opioid recreational drugs use is associated with incident HIV infection in this prolonged HIV outbreak. There is an urgent need to formulate an effective public health response to mitigate the risk.

The Examination of Viral Characteristics of HIV-1 CRF07_BC and Its Potential Interaction with Extracellular Galectin-3

HIV-1 CRF07_BC is a B’ and C subtype recombinant emerging virus and many of its viral characteristics remain unclear. Galectin-3 (Gal3) is a β-galactose binding lectin that has been reported as a pattern recognition receptor (PRR) and is known to mediate adhesion between cells and microbes. This study aims to examine the viral characteristics of HIV-1 CRF07_BC virus and the role of extracellular galectin-3 in HIV-1 CRF07_BC infection. A total of 28 HIV-1+ injecting drug users (IDUs) were recruited and 24 (85.7%) were identified as HIV-1 CRF07_BC. Results indicate that significant higher serum galectin-3 was measured in CRF07_BC infected patients and CRF07_BC infection triggered significant galectin-3 expression (p < 0.01). Viral characteristics demonstrate that CRF07_BC virions display a higher level of envelope gp120 spikes. The virus infectivity assay demonstrated that co-treatment with galectin-3 significantly promoted CRF07_BC attachment and internalization (p < 0.01). A co-immunoprecipitation assay showed that pulldown galectin-3 co-precipitated both CD4 and gp120 proteins. Results from an enzyme-linked immunosorbent assay (ELISA) indicate that the galectin-3 promoting effect occurs through enhancement of the interaction between gp120 and CD4. This study suggests that CRF07_BC was predominant in HIV-1+ IDUs and CRF07_BC utilized extracellular galectin-3 to enhance its infectivity via stabilization of the gp120-CD4 interaction.

Amino Acid Deletions in p6Gag Domain of HIV-1 CRF07_BC Ameliorate Galectin-3 Mediated Enhancement in Viral Budding

HIV-1 CRF07_BC is a recombinant virus with amino acid (a.a.) deletions in p6^Gag, which are overlapped with the Alix-binding domain. Galectin-3 (Gal3), a β-galactose binding lectin, has been reported to interact with Alix and regulate HIV-1 subtype B budding. This study aims to evaluate the role of Gal3 in HIV-1 CRF07_BC infection and the potential effect of a.a. deletions on Gal3-mediated regulation. A total of 38 HIV-1+ injecting drug users (IDUs) were enrolled in the study. Viral characterization and correlation of Gal3 were validated. CRF07_BC containing 7 a.a. deletions and wild-type in the p6^Gag (CRF07_BC-7d and -wt) were isolated and infectious clones were generated. Viral growth kinetic and budding assays using Jurkat-CCR5/Jurkat-CCR5-Gal3 cells infected with CRF07_BC were performed. Results indicate that 69.4% (25/38) of the recruited patients were identified as CRF07_BC, and CRF07_BC-7d was predominant. Slow disease progression and significantly higher plasma Gal3 were noted in CRF07_BC patients (p < 0.01). Results revealed that CRF07_BC infection resulted in Gal3 expression, which was induced by Tat. Growth dynamic and budding assays indicated that Gal3 expression in Jurkat-CCR5 cells significantly enhanced CRF07_BC-wt replication and budding (p < 0.05), while the promoting effect was ameliorated in CRF07_BC-7d. Co-immunoprecipitation found that deletions in the p6^Gag reduced Gal-3-mediated enhancement of the Alix–Gag interaction.

Characterization of a Novel HIV-1 CRF01_AE/CRF07_BC Recombinant Virus Form in Guizhou, China

We identified a novel CRF01_AE and 07_BC HIV-1 recombinant form in Guizhou province in southwest China. The phylogenetic analysis of the near full-length sequence reveals that it was divided into five segments by four breakpoints, and the CRF01_AE regions of the recombinant were clustered with subcluster 4 lineage of CRF01_AE, which mainly circulated among men who have sex with men (MSM) in China. The CRF07_BC regions of the recombinant were clustered with CRF07_BC lineage, which circulated among Chinese MSM. This is the first detection of a novel HIV-1 second-generation recombinant form (CRF07_BC/CRF01_AE) in Guizhou, which shows the increasing significance of heterosexual transmission contributing to the complexity of the HIV-1 epidemic in southwest China, and more effort measures should be taken to monitor the genetic evolution of HIV-1 strains and prevent HIV-1 transmissions.

Genomic Characterization of a New HIV-1 CRF01_AE/CRF07_BC Recombinant Virus Form in Guizhou in Southwest China

A novel HIV-1 second-generation recombinant form (CRF01_AE/CRF07_BC) was isolated from an HIV-positive subject among men who have sex with men (MSM) in Guizhou province in Southwest China. Recombinant analyses of the near full-length genome suggested that the strain was composed of CRF01_AE and CRF07_BC with one region of CRF07-BC inserted into a CRF01-AE backbone. Further analysis indicated that the CRF01_AE regions of the recombinant were highly clustered together with a subcluster 4 lineage of CRF01_AE, which is exclusively circulating among MSM in China. The CRF07_BC region of the recombinant was clustered with the CRF07_BC cluster, which was identified among MSM. The emergence of the novel HIV-1 recombinant may be a harbinger of more novel intersubtypes recombinants occurring in Guizhou province in Southwest China, and was of great important in understanding the dynamics and complexity of the HIV-1 epidemic in this region.

Characterization of the Drug Resistance Profiles of Patients Infected with CRF07_BC Using Phenotypic Assay and Ultra-Deep Pyrosequencing

The usefulness of ultra-deep pyrosequencing (UDPS) for the diagnosis of HIV-1 drug resistance (DR) remains to be determined. Previously, we reported an explosive outbreak of HIV-1 circulating recombinant form (CRF) 07_BC among injection drug users (IDUs) in Taiwan in 2004. The goal of this study was to characterize the DR of CRF07_BC strains using different assays including UDPS. Seven CRF07_BC isolates including 4 from early epidemic (collected in 2004–2005) and 3 from late epidemic (collected in 2008) were obtained from treatment-naïve patient’s peripheral blood mononuclear cells. Viral RNA was extracted directly from patient’s plasma or from cultural supernatant and the pol sequences were determined using RT-PCR sequencing or UDPS. For comparison, phenotypic drug susceptibility assay using MAGIC-5 cells (in-house phenotypic assay) and Antivirogram were performed. In-house phenotypic assay showed that all the early epidemic and none of the late epidemic CRF07_BC isolates were resistant to most protease inhibitors (PIs) (4.4–47.3 fold). Neither genotypic assay nor Antivirogram detected any DR mutations. UDPS showed that early epidemic isolates contained 0.01–0.08% of PI DR major mutations. Furthermore, the combinations of major and accessory PI DR mutations significantly correlated with the phenotypic DR. The in-house phenotypic assay is superior to other conventional phenotypic assays in the detection of DR variants with a frequency as low as 0.01%.

First Appearance of HIV-1 CRF07_BC and CRF08_BC Outside China

Neither full length genomic sequence of CRF07_BC nor that of CRF08_BC was found in any other countries since they originated in Yunnan, China, in early 1990s. Here, we first report that CRF07_BC and CRF08_BC appeared among intravenous drug users in Shan state of Myanmar bordering Yunnan, and confirmed that they spread from China to Myanmar. The introduction of CRF07_BC and CRF08_BC in northern Myanmar may forebode a changing subtype epidemic in Southeast Asia.

A Smartphone Application Supporting Recovery from Heroin Addiction: Perspectives of Patients and Providers in China, Taiwan, and the USA

Smartphone-based interventions are increasingly used to support self-monitoring, self-management, and treatment and medication compliance in order to improve overall functioning and well-being. In attempting to develop a smartphone application (S-Health) that assists heroin-dependent patients in recovery, a series of focus groups (72 patients, 22 providers) were conducted in China, Taiwan, and the USA to obtain their perspectives on its acceptance and potential adoption. Data were analyzed according to the Diffusion of Innovation (DOI) theory of characteristics important to the adoption of innovation. Important to Relative Advantage, USA participants cited S-Health's potential ability to overcome logistical barriers, while those in China and Taiwan valued its potential to supplement currently limited services. In terms of Compatibility, participants across sites reported recovery needs and goals that such an application could be helpful in supporting; however, its utility during strong craving was questioned in China and Taiwan. Important factors relevant to Complexity included concerns about smartphone access and familiarity, individualization of content, and particularly in China and Taiwan, participants wanted assurance of privacy and security. The study results suggest a general acceptance, but also indicate cultural variations in access to therapeutic and other social support systems, legal repercussions of substance use, societal perceptions of addiction, and the role of family and other social support in recovery. Taking these factors into consideration is likely to increase diffusion as well as effectiveness of these smartphone-based interventions.

Evaluation of performance of human immunodeficiency virus antigen/antibody combination assays in Taiwan

BACKGROUND

The fourth-generation human immunodeficiency virus (HIV) combination assay, which can simultaneously detect the presence of anti-HIV antibody and HIV antigen, has been shown to shorten the window period in HIV diagnosis compared with the third-generation HIV antibody immunoassay. This study was aimed to determine the performance of HIV combination assays in Taiwan, where the HIV-1 seroprevalence is 0.007% and HIV-2 infection has never been reported.

METHODS

Performance of three fourth-generation HIV Ag/Ab combination assays (Dia.Pro, Wantai, and Bio-Rad) and one third-generation HIV Ab immunoassay (AxSYM HIV 1/2 gO) was assessed.

RESULTS

A total of 152 specimens, including 86 confirmed HIV-seropositive and 66 HIV-seronegative samples, were used in the study. The sensitivity of four assays varied from 98.8% to 100%, and specificity varied from 98.5% to 100%. Performance of the 75 equivocal samples, the HIV status of which was confirmed later, in terms of negative prediction varied from 81.8% to 87.5%. The Bio-Rad and Dia.Pro assays exhibited higher sensitivity for the detection of p24 antigen among the three fourth-generation HIV combination assays.

CONCLUSION

The three fourth-generation HIV Ag/Ab combination assays exhibited better sensitivity, specificity, and negative prediction than the third-generation HIV Ab immunoassay.

Molecular Epidemiology of HIV-1 Infection among Men who Have Sex with Men in Taiwan in 2012

The number of men who have sex with men (MSM) infected with HIV-1 in Taiwan has increased rapidly in the past few years. The goal of this study was to conduct a molecular epidemiological study of HIV-1 infection among MSM in Taiwan to identify risk factors for intervention. Voluntary counseling program and anonymous testing were provided to patrons at 1 gay bar, 7 night clubs and 3 gay saunas in Taipei and New Taipei Cities in 2012. HIV-1 subtypes were determined using gag subtype-specific PCR and phylogenetic analysis by env sequences. Recent HIV-1 infection was determined using LAg-Avidity EIA. In-depth interviews and questionnaires were used to identify risk factors. The prevalence and incidence of HIV-1 among MSM in Taiwan were 4.38% (53/1,208) and 3.29 per 100 person-years, respectively. Of 49 cases genotyped, 48 (97.9%) were infected with subtype B and 1 with CRF01_AE (2%). Phylogenetic analysis of 46 HIV-1 strains showed that 25 (54.4%) subtype B strains formed 9 clusters with each other or with other local strains. The CRF01_AE case clustered with a reference strain from a Thai blood donor with bootstrap value of 99. Multivariate logistic regression analysis showed that risk factors associated with HIV-1 infection included use of oil-based solution as lubricant (vs. saliva or water-based lubricants, OR= 4.23; p <0.001); exclusively receptive role (vs. insertive role, OR= 9.69; p <0.001); versatile role (vs. insertive role, OR= 6.45; p= 0.003); oral sex (vs. insertive role, OR= 11.93; p= 0.044); times of sexual contact per week (2-3 vs. zero per week, OR= 3.41; p= 0.021); illegal drug use (OR= 4.12; p <0.001); and history of sexually transmitted diseases (OR= 3.65; p= 0.002). In conclusion, there was no new HIV-1 subtype or circulating recombinant form responsible for the increase of HIV-1 among MSM in Taiwan in 2012. Misuse of oil-based solution as lubricant is a new risk factor identified among MSM in Taiwan. The Taiwan's Centers for Disease Control has created a video (www.youtube.com/watch?v=BinExvvOTMM&feature=iv&src_vid=BW81-PfmY3E&annotation_id=annotation_2436493705) to correct such misconception in its AIDS prevention campaign.

Changing patterns of HIV epidemic in 30 years in East Asia

The HIV epidemic in East Asia started relatively late compared to the rest of the world. All countries or areas, except for North Korea, had reported HIV and AIDS cases, with China being the major contributor to the epidemic. Though initially driven by injecting drug use in China, East Asia did not experience an explosive spread. Strong commitment in China and early harm reduction programs in Taiwan managed to reduce transmission substantially among injecting drug users. In contrast to China and Taiwan, injection drug use has accounted just a little, if not at all, for the spread of HIV in other East Asian counties. However, following a global trend, sexual contact has become a major route of infection across the region. While much progress has been achieved in this region, with the epidemic among other key populations relatively stable, the emerging epidemic through sex between men is a growing concern. Recent estimates suggest that HIV prevalence among men who have sex with men (MSM) has reached 6.3 % in China, 7.5 % in Mongolia, and ranges between 8.1 %-10.7 % in Taiwan and between 2.7 %- 6.5 % in South Korea. In Japan, 74 % of male HIV cases were among MSM in 2012, while Hong Kong has witnessed a sharp increase of HIV cases among MSM since 2004. There is urgent need to address issues of discrimination and stigma toward homosexuality, and to strengthen the strategies to reach and care for this population.

Patients infected with CRF07_BC have significantly lower viral loads than patients with HIV-1 subtype B: mechanism and impact on disease progression

The circulating recombinant form (CRF) 07_BC is the most prevalent HIV-1 strain among injection drug users (IDUs) in Taiwan. It contains a 7 amino-acid deletion in its p6gag. We conducted a cohort study to compare viral loads and CD4 cell count changes between patients infected with subtype B and CRF07_BC and to elucidate its mechanism. Twenty-one patients infected with CRF07_BC and 59 patients with subtype B were selected from a cohort of 667 HIV-1/AIDS patients whom have been followed up for 3 years. Generalized estimated equation was used to analyze their clinical data and the results showed that patients infected with CRF07_BC had significantly lower viral loads (about 58,000 copies per ml less) than patients with subtype B infection (p = 0.002). The replicative capacity of nine CRF07_BC and four subtype B isolates were compared and the results showed that the former had significantly lower replicative capacity than the latter although all of them were CCR5- tropic and non-syncytium inducing viruses. An HIV-1-NL4-3 mutant virus which contains a 7 amino-acid deletion in p6gag (designated as 7d virus) was generated and its live cycle was investigated. The results showed that 7d virus had significantly lower replication capacity, poorer protease-mediated processing and viral proteins production. Electron microscopic examination of cells infected with wild-type or 7d virus demonstrated that the 7d virus had poorer and slower viral maturation processes: more viruses attached to the cell membrane and higher proportion of immature virions outside the cells. The interaction between p6gag and Alix protein was less efficient in cells infected with 7d virus. In conclusion, patients infected with CRF07_BC had significantly lower viral loads than patients infected with subtype B and it may due to the deletion of 7 amino acids which overlaps with Alix protein-binding domain of the p6gag.

Ascertaining the 2004-2006 HIV type 1 CRF07_BC outbreak among injecting drug users in Taiwan

Objective

To ascertain the explosive 2004–2006 outbreak of HIV-1 CRF07_BC among intravenous drug users (IDU) in Taiwan, which more than doubled the total number of reported HIV cases in less than 3 years, resulting in a 45-fold increase in cumulative IDU/HIV cases and a 40-fold increase in previously seldom-reported female IDU/HIV cases.

Methods

A mathematical model was utilized to fit the monthly case data, in order to estimate the turning points (peak incidence) and the reproduction number R of the outbreak. Furthermore, correlation analysis was carried out to assess the correlation between infections among the male and female IDUs.

Results

Model fit revealed a two-wave epidemic during April 2004–March 2007. The larger second wave started shortly after May 2005 and peaked in October 2005 before gradually subsiding. R was estimated to be 3.15 (3.14–3.16) and 27.21 (26.73–28.05) for the two respective waves. The time series of monthly differences in male and female case data were found to be most significantly correlated at lag 0 (i.e., r > 0.7) with r = 0.906 and 0.804, respectively in each direction. The Granger causality test indicated that the male time series caused the corresponding female time series with a lag of 2 months or less.

Conclusions

The modeling results revealed the presence of a small first wave in 2004, before an explosion of cases after May 2005. Furthermore, a harm reduction program implemented in August 2005 contributed to the downturn in the epidemic after October. Correlation results also suggest that the upsurge in male HIV cases led to the subsequent drastic surge in female cases.

Near full-length genomic characterization of a HIV type 1 BC recombinant strain from Manipur, India

Genetic complexity of HIV-1 is brought about by recombination between HIV-1 subtypes which leads to the development of epidemiologically significant founder strains. In the present study, the near full-length genome sequence of an HIV-1 isolate from an injecting drug user of Manipur (India) was determined, which evidenced the presence of a novel HIV-1 BC recombinant strain. Near full-length genome was amplified by polymerase chain reaction using primer walking approach. The recombination break points were detected using bootscan and simplot analyses. This isolate exhibited a mosaic structure consisting of subtype C backbone with subtype B insertions at the upstream of pol gene (3026-3259) and the downstream of env gene which spanned till the nef gene (8183-8961). Phylogenetic relationships determined with neighbor-joining trees, revealed that the subtype C sequences clustered with sequences from Indian subtype C HIV-1 strains, and the subtype B sequences clustered with HIV-1 subtype B strains from Thailand. This finding may create a complex scenario of HIV-1 epidemic among the injecting drug users of Manipur in near future.

Mortality among a cohort of drug users after their release from prison: an evaluation of the effectiveness of a harm reduction program in Taiwan

AIMS

To determine the effect of methadone maintenance therapy (MMT) on mortality among injection drug users.

DESIGN

A cohort of prisoners with a history of injecting opiates who were followed after their release from prison in July 2007. Mortality between July 2007 and December 2008 was determined by linking the National Death Registry with the Methadone Maintenance Treatment (MMT) database.

SETTING

Taiwan.

PARTICIPANTS

A total of 4357 amnestied prisoners with a history of opiate injection.

MEASUREMENTS

The total mortality rates (MR) among the cohort were calculated based on their person-time contribution to methadone attendance and re-incarceration during follow-up. We used survival methods with MMT and re-incarceration as time-varying covariates adjusted for length of follow-up in the community.

RESULTS

A total of 142 deaths occurred: 13 in the 1st week after release [MR = 13.7/100 person-years (pyrs)], which was greater than that in the next 4 weeks [MR = 3.2/100 pyrs, relative rate (RR) = 4.3, P < 0.001]. Overall, 1982 (46%) subjects enrolled in MMT; however, 1282 of them discontinued MMT after enrolling.

FINDINGS

The mortality among those who continued in MMT attendance was lower (MR = 0.24/100 pyrs) than those who never enrolled in MMT (MR = 2.6/100 pyrs) or those who enrolled but dropped out of MMT (MR = 7.0/100 pyrs) after adjusting for age, gender and human immunodeficiency virus status at amnesty (RR = 0.07).

CONCLUSIONS

In ex-prisoners in Taiwan with a history of opiate injecting, enrollment and continued participation in methadone maintenance treatment is associated with substantially lower mortality.

Surveillance of HIV type 1 recent infection and molecular epidemiology among different risk behaviors between 2007 and 2009 after the HIV type 1 CRF07_BC outbreak in Taiwan

The objective of this study was to analyze recent infections and the molecular epidemiology of human immunodeficiency virus type 1 (HIV-1) among different risk groups since the outbreak of circulating recombinant form CRF07_BC among intravenous drug users (IDUs) in 2004 in Taiwan. Phylogenetic analysis was performed using the env and pol fragment sequences amplified from these specimens. The BED IgG capture incidence EIA (BED-CEIA assay) was used to determine recent infections. Among the 683 HIV-1-positive individuals enrolled between 2007 and 2009, 394 (57.7%) were subtype B, 260 (38.1%) were CRF07_BC, 26 (3.8%) were CRF01_AE, two (0.3%) were CRF08_BC, and one (0.1%) was CRF06_cpx. While the percentage of CRF07_BC decreased (58.5-17.9%, p < 0.001) from 2007 to 2009, the percentage of subtype B increased (37.6% to 74.9%, p < 0.001). A concordant decrease in the proportion of recent infections to new infections among IDUs (63.6% to 9.8%, p < 0.001), accompanied with an increase of the proportion of recent infections in MSM (men having sex with men) (22.4-67.1%, p = 0.77) and heterosexual groups (13.1- 23.2%, p = 0.852), was observed. The decrease in CRF07_BC infections and the reduction in the proportion of recent infections among IDUs reflected the success of harm reduction strategies initiated by the government in 2005.

Heroin dependence and bloodborne virus transmission behaviors for HIV infection among newly incarcerated injection drug users in Taiwan

The purpose of the study was to determine heroin dependence and risky behaviors associated with human immunodeficiency virus (HIV) infection among newly incarcerated injection drug users (IDUs). Three self-administrated questionnaires were collected among 450 newly incarcerated male heroin users during 2005-2007. Inmates were categorized as heroin-dependent if they met three or more of the six ICD-10 criteria. Heroin-dependent inmates had higher scores of bloodborne virus transmission risk than non-dependent IDUs (12.8 ± 16.0 vs. 7.2 ± 11.5, p < 0.001). Multiple logistic regression analysis indicated that heroin dependence was a significant moderator of the association between risky injection behaviors and HIV infection. It is crucial to integrate substance treatment with behavioral interventions into harm reduction programs to prevent bloodborne virus transmission among IDUs.

Molecular epidemiology of hepatitis D virus infection among injecting drug users with and without human immunodeficiency virus infection in Taiwan

An outbreak of human immunodeficiency virus (HIV) infection occurred among injecting drug users (IDU) in Taiwan between 2003 and 2006, when an extremely high prevalence of hepatitis C virus (HCV) infection was also detected. To determine whether clusters of hepatitis D virus (HDV) infection occurred in this outbreak, 4 groups of subjects were studied: group 1, HIV-infected IDU (n = 904); group 2, HIV-infected non-IDU (n = 880); group 3, HIV-uninfected IDU (n = 211); and group 4, HIV-uninfected non-IDU (n = 1,928). The seroprevalence of hepatitis B virus (HBV) was 19.8%, 18.4%, 17.1%, and 6.7%, and HDV seroprevalence among HBV carriers was 75.4%, 9.3%, 66.7%, and 2.3%, for groups 1, 2, 3, and 4, respectively. Ninety-nine of 151 (65.6%) HDV-seropositive IDU had HDV viremia: 5 were infected with HDV genotype I, 41 with genotype II, 51 with genotype IV, and 2 with genotypes II and IV. In the phylogenetic analysis, only one cluster of 4 strains within the HDV genotype II was identified. Among patients with HCV viremia, a unique cluster within genotype 1a was observed; yet, patients within this cluster did not overlap with those observed in the HDV phylogenetic analysis. In summary, although IDU had a significantly higher HDV seroprevalence, molecular epidemiologic investigations did not support that HDV was introduced at the same time as HCV among IDU.

Molecular epidemiology of HIV-1 subtype B, CRF01_AE, and CRF07_BC infection among injection drug users in Taiwan

OBJECTIVE

An explosive outbreak of HIV-1 circulating recombinant form (CRF) 07_BC among injection drug users (IDUs) in Taiwan was first reported in 2004 and reach the peak in 2005. The objectives of this study were to investigate the molecular epidemiology of different HIV-1 subtypes and their associated risk factors among Taiwanese IDUs in 2004 and 2005.

METHODS

Questionnaires and blood specimens were collected from inmates from 4 detention centers and 2 prisons. HIV-1 subtypes were determined using nested polymerase chain reactions with multiplex primers and phylogenetic analyses. A case-control study was conducted to elucidate risk factors associated with CRF07_BC infection.

RESULTS

A total of 93.8%, 4%, and 2.2% of 451 inmates with IDU history were infected with CRF07_BC, subtype B, and CRF01_AE, respectively. Besides CRF07_BC, a new outbreak of CRF01_AE infection was identified among IDUs from central region. Multivariate analysis showed that sharing dissolved heroine solution [odds ratio (OR) = 17.2], sharing syringes (OR = 34), number of persons sharing syringes (2 vs. 1, OR = 3.1), and lower educational level (OR = 2.3) were risk factors associated with CRF07_BC infection.

CONCLUSIONS

Sharing dissolved heroine solution is a neglected risk factor associated with HIV-1 infection and it should be emphasized in the AIDS education and harm reduction programs immediately.

Genetic characterization analysis of the tat exon-1 region of HIV type 1 CRF07_BC strains in China

HIV-1 CRF07_BC is one of the predominant strains in China, however, there have been few reports about the genetic characteristics of accessory genes of this strain. In this study, 236 CRF07_BC tat exon-1 regions were obtained by nested PCR and were followed by sequencing. Our results showed some variations in crucial functional domains, especially in the basic region. There were two conserved amino acid variations in the 1 approximately 56 aa fragment of tat gene exon-1 of 07_BC isolates, which were R7N (71.6%) and R46F (90.3%), as compared with subtype B' strains in Thailand. The analysis of the sequences provides some valuable information for an exploration of the predominance of the HIV-1 CRF07_BC epidemic.

Molecular epidemiology of HCV genotypes among injection drug users in Taiwan: Full-length sequences of two new subtype 6w strains and a recombinant form_2b6w

Human immunodeficiency virus type 1 (HIV-1) circulating recombinant form (CRF) 07_BC strain has caused serious outbreaks among injection drug users in Taiwan since 2004. The objective of this study was to conduct a molecular epidemiological study of HCV genotypes in intravenous drug users in Taiwan. Blood samples and questionnaires from 591 intravenous drug users infected with HIV-1 were collected nationwide. In total, 180 samples were selected for HCV genotyping using multiplex PCR and phylogenetic analysis of the core, E1 and NS5B regions. The Inno-Lipa assay was used to confirm multiple infections with different genotypes. Eighty percent had a single infection with subtype 1b being the most common subtype (24%), 12% had double infections and two had triple infections. In addition, three recombinant forms (RFs)-2a1a, 3a1b, and 2b6w were identified. Phylogenetic analyses showed that the 3a, 6a, and 6n strains were clustered with strains present in Thailand and mainland China. Full-length sequence analysis showed that two 6w strains shared 89.4-90.2% sequence homology with the 6(r) strain from the Guangdong Province, China. Bootscan analysis revealed that the recombination breakpoint of RF_2b6w was located at the NS2-NS3 junction. In summary, the distribution of HCV genotypes among Taiwanese intravenous drug users was complex and more than 12% of the drug users were infected with more than one genotype of HCV.

Genetic and temporal dynamics of human immunodeficiency virus type 1 CRF07_BC in Xinjiang, China

To explore the temporal genetic variation of human immunodeficiency virus type 1 CRF07_BC and reconstruct its epidemic in Xinjiang, China, we studied 216 C2–V4 fragments of env genes sampled from 1996 to 2008. Phylogenetic analysis indicates that the viruses prevailing in Xinjiang form a large monophyletic cluster and may have originated from a common ancestor. The epidemic in Xinjiang was probably established around 1995 (95 % confidence interval, 1994–1996). We noted an increased diversity of CRF07_BC over time, with a rapid evolutionary rate we estimated to be 8.3×10−3 substitutions per site per year in the env gene. After 5–6 years of the epidemic (1997–2002), the transmission rate of CRF07_BC in Xinjiang slowed down, although CRF07_BC infection remained at a high prevalence.

Risky behaviors for HIV infection among male incarcerated injection drug users in Taiwan: a case-control study

Taiwan has experiencing an outbreak of HIV infection among injection drug users (IDUs) since 2003. A case-control study was conducted to determine the behavioral characteristics associated with HIV infection among IDUs. The study identified 120 inmates with HIV infection and 121 matched HIV-negative controls from prisons. Data were collected by face-to-face interviews. The study found 48.1% of IDUs shared needles, less than a half of IDUs reported sexual intercourse before incarceration and only 19.7% used condoms. The multivariate logistic regression analysis, adjusted for years of heroin injection, found that HIV infection was independently associated with the use of a used needle or syringe at the latest injection (odds ratio [OR], 8.2; 95% confidence interval [CI], 3.3-20.2, p<0.001), having HIV-infected relatives or friends (OR, 5.7; 95%CI, 2.5-13.2, p<0.001) and sharing containers with others (OR, 3.3; 95%CI, 1.2-8.8, p=0.02). Our findings highlight the importance of needle exchange programs along with HIV-prevention education.

A pilot study of HIV education on readiness to change on substance use, AIDS knowledge, self-efficacy for risk reduction among male drug-dependent inmates

Taiwan is experiencing an outbreak of human immunodeficiency virus infection among injection drug users. The purpose of the study was to determine the impact of a Transtheoretical Model-based HIV education program among drug-dependent inmates. A single group pre/post design was used to evaluate shortened impacts among 136 inmates who were arrested for illicit drug use and had attended a brief HIV education program in 2005. A repeated-measures analysis of variance indicated positive changes in AIDS knowledge (F > = 104.16, p < 0.001), self-efficacy to reduce HIV-risk behaviors (F = 26.5, p < 0.001), and readiness of change on substance use (F = 4.83, p = 0.03). The study findings showed that a brief TTM-based HIV education program can be effective for drug-dependent inmates.

Molecular epidemiological identification of Neisseria gonorrhoeae clonal clusters with distinct susceptibility profiles associated with specific groups at high risk of contracting human immunodeficiency virus and syphilis

From April 2006 to August 2007, a total of 146 Neisseria gonorrhoeae isolates collected from 139 male patients in Taipei, Taiwan, were analyzed by N. gonorrhoeae multiantigen sequence typing (NG-MAST) and antibiotic susceptibility testing. The resistance rates of all isolates to ciprofloxacin, cefpodoxime, and cefixime were 76.7 (112/146), 21.2 (31/146), and 16.4% (24/146), respectively. NG-MAST identified 71 sequence types (STs), of which 21 STs contained 2 to 21 isolates. The isolates that belonged to the three major ST clusters typically were from patients who had specific epidemiological characteristics (such as sexual orientation and human immunodeficiency virus status). The major ST clones exhibited distinct resistance profiles and are associated with specific groups at high risk of human immunodeficiency virus and syphilis infections.

Seroprevalence of viral hepatitis and sexually transmitted disease among adults with recently diagnosed HIV infection in Southern Taiwan, 2000-2005: upsurge in hepatitis C virus infections among injection drug users

BACKGROUND/PURPOSE

The purpose of this study was to compare the seroprevalence of viral hepatitis and sexually transmitted disease (STD) co-infections among three populations at risk recently diagnosed with HIV infection.

METHODS

A retrospective review of medical records was performed to determine the prevalence of several co-infections among adults recently diagnosed with HIV infection between 2000 and 2005 at National Cheng Kung University Hospital in Tainan, Taiwan.

RESULTS

Among a total of 484 adults, 124 (25.6%) were men having sex with men (MSM), 105 (21.7%) were heterosexual adults, and 255 (52.7%) were injection drug users (IDUs). The case number of adults with recently diagnosed HIV infection increased annually, from 27 in 2000 to 142 in 2005 (p < 0.001). This trend appeared to be attributable to the upsurge in HIV infection among IDUs beginning in 2003. At the time of HIV diagnosis, mean CD4+ counts were significantly higher and plasma HIV-1 RNA loads were lower in the IDU group than the MSM or heterosexual groups. The hepatitis B virus (HBV) carrier rate was similar in all three groups, with an average rate of 16.5%. The prevalence of treponemal antibody and Entamoeba histolytica indirect hemagglutination antibody was higher in MSM (37.5% and 9.4%, respectively) than in heterosexuals (19.6% and 7.3%, respectively) or IDUs (3.2% and 2.1%). The seroprevalence of hepatitis A virus infection increased with age, with 94.2% (97/103) of patients who were older than 40 years. Hepatitis C virus (HCV) or HBV-HCV co-infections were noted more often in IDUs (97.9% and 16.9%, respectively) than in heterosexuals (10.9% and 2.2%, respectively) and MSM (5.3% and 3.6%, respectively).

CONCLUSION

There was a recent upsurge in HIV-HCV co-infected IDUs in southern Taiwan. A higher rate of co-infection with STDs among HIV-infected MSM highlights the need for integrated STD control efforts in current HIV prevention programs.

Evidence of a novel B/C recombinant exhibiting unique breakpoints of near full-length HIV type 1 genome from Northeastern India

Despite the predominance of the HIV-1 clade C in India, the presence of other subtypes and recombinants has been reported. Here we report the identification of a novel HIV-1 B/C recombinant isolated from Northeast India and characterized near full length genome of the recombinant virus. Bootscan analysis of the nearly full-length genome showed a unique mosaic structure consisting of a subtype B backbone with three subtype C genome insertions. Breakpoint analyses revealed insertion of fragments belonging to subtype C at positions 1853-2223 in gag and 3025-3759 and 3998-5073 in pol. Phylogenetic analysis revealed that the segments of subtype B clustered with sequences of subtype B viruses reported from Thailand whereas segments of subtype C clustered with sequences of subtype C viruses reported from India. We report the mosaic structure that is distinct to HIV-1 B/C recombinant viruses reported to date.

Cost-effectiveness of Highly Active Antiretroviral Therapy for HIV Infection in Taiwan

BACKGROUND/PURPOSE

Since the late 1980s, the Taiwanese government has provided all HIV-infected citizens with free access to antiretroviral therapy. Recently, there is controversy as to whether or not free access to expensive highly active antiretroviral therapy (HAART) should be continued for HIV-infected patients. This study aimed to evaluate the cost-effectiveness of HAART therapy.

METHODS

HAART-associated improvement in survival was obtained by analyzing the follow-up data of all HIV-positive patients identified during April 1984 to March 1997 (pre-HAART era) and May 1997 to April 2003 (HAART era) in Taiwan. Data on quality of life in HIV-positive patients was obtained from a cross-sectional survey of 224 patients using standard gamble method and World Health Organization Quality of Life-BREF instrument. Information regarding the cost of HAART was obtained from the National Health Insurance (NHI).

RESULTS

In 2000, the average annual NHI expenditure on HAART per HIV-positive patient receiving HAART was NT$210,018 (US$6177, at an exchange rate of 34.0 NT$/US$). In the AIDS group, the cost was NT$176,441 (US$5189) per life year gained and NT$241,700 (US$7109) per quality-adjusted life year gained. For non-AIDS patients, the corresponding costs were NT$226,156 (US$6652) and NT$332,582 (US$9782), respectively. These estimates have not yet included the additional cost savings from HAART-associated reduction in hospitalization and use of antimicrobial agents for opportunistic infections, and the additional life years gained from the reduction in HIV transmission under the universal availability of HAART.

CONCLUSION

HAART for HIV infection is cost-effective, especially when the societal and epidemiologic factors are considered. We recommend that the policy of providing free HAART to all HIV-infected citizens be continued.