An unusual cluster of HIV-1 B/F recombinants in an Asian population

Characterization of an imported HIV-1 A1/A7/G recombinant in China

BACKGROUND

International migration has accelerated the HIV-1 spread across national borders, gradually reducing the restrictions on the geographical distribution of HIV-1 subtypes. Subtypes A and G are globally recognized as the third and sixth most dominant HIV-1 genotypes, mainly prevalent in Africa, but rarely detected in China. Here we reported an imported HIV-1 recombinant which was composed of sub-subtypes A1 and A7 of subtype A and subtype G genes in a Chinese female. This virus was the first HIV-1 recombinant including A7 genes reported in the world.

CASE PRESENTATION

The near full-length genome (NFLG) was obtained from the plasma sample of the female in an HIV-1 molecular epidemiological survey with 853 participants in China. Phylogenetic analyses showed that this NFLG sequence contains three A7 segments, four G segments and one A1 segment with seven breakpoints, and all these segments were closely related to HIV-1 references circulating in Africa. The evidence from epidemiological investigation indicated that this female participant had a more-than-two-years heterosexual contact history with a fixed partner from Nigeria, a country in west Africa, which further supported the results of phylogenetic analyses. By the Bayesian phylogenetic analyses, the times of most recent common ancestors (tMRCA) of the partial pol gene (nt2308-3284, A7 region) and full-length vpr-vpu plus partial env gene (nt5534-6858, G region) were estimated around 1989 and 1984, respectively.

CONCLUSIONS

In this study, by using the NFLG sequencing, we identified an imported HIV-1 A1/A7/G recombinant which was estimated to originate around 1980s in Africa and introduced into China with international migration. This study highlighted the complexity of the global HIV-1 epidemic, the necessity of using genome sequences to determine HIV-1 genotypes and the importance of real-time monitoring of HIV-1 infection among international migrants and travelers.

Genetic Characteristics of HIV-1 CRF12_BF First Identified in Guangdong Province, China

Multiple HIV-1 genotypes were found circulating in Guangdong Province, China, as this province is located in South China and has a high frequency of international trade. In this study, we report the near full-length genome (NFLG) of CRF12_BF that was identified from a male patient in Guangzhou city, Guangdong Province; this is the first time CRF12_BF has been reported in mainland China. The NFLG was amplified, and then PCR products were sequenced by Sanger sequencing. The CRF12_BF strain was confirmed by the Basic Local Alignment Search Tool and a neighbor-joining phylogenetic tree. In addition, this CRF12_BF strain was confirmed to contain the non-nucleoside reverse transcriptase inhibitor mutation E138A associated with potential low-level resistance against efavirenz and low-level resistance against rilpivirine by the Stanford University HIV Drug Resistance Database program. The analyzed sequence data in this study will provide more information on the HIV epidemic in China.

Triangulating Syndemic Services and Drug Treatment Policy: Improving Drug Treatment Portal Locations in Baltimore City

THE PROBLEM

The prevalence of injection drug use (IDU) and incidence of human immunodeficiency virus (HIV) remain high in Baltimore, where IDU is a primary HIV risk factor. Substance use disorders and HIV are related syndemically--their causes and consequences interact synergistically. Baltimore is increasingly considering the syndemic relationship of substance use disorders, IDU, and HIV in making decisions about drug treatment funding and location.

PURPOSE OF ARTICLE

Our goal was to empirically identify the optimal location of new drug treatment programs through the development and application of a novel, practical tool.

KEY POINTS

Syndemic triangles were constructed to measure and visualize unmet need for drug treatment services. These data were used to determine priority zones for new treatment centers.

CONCLUSIONS

The application of this tool helped inform strategies for locating drug treatment services in Baltimore, and its successful use suggests its potential value in other metropolitan areas.

A cluster of patients with recombinant B/F HIV-1 infection: epidemiological, clinical, and virological aspects

Migratory processes have caused changes in human immunodeficiency virus (HIV) epidemiology and non-B subtypes are now playing an increasing role. In a cohort of 553 HIV-infected outpatients tested to identify non-B isolates, the largest group consisted of 13 subjects with a recombinant B/F form (prevalence 2.4%). Sequencing and phylogenetic analyses described a B/F recombinant clade with anomalous breakpoints that did not allow it to be classified as CRF12_BF. Viral load was not quantified efficiently because of a mismatch in the primers and probes used by commercial assays. An assessment of the clinical management, and epidemiological, immunological, and virological characteristics of these patients, who were receiving non-nucleoside reverse transcriptase inhibitor (NNRTI)- or protease inhibitor (PI)-based regimens, showed that the immunological and virological mismatch delayed the start of treatment by a mean of 6.8 months. Therapy was started in nine patients. Both NNRTI- and PI-based regimens led to full virological suppression after a mean 36 weeks of treatment; the PI-based regimens proved to be more effective in terms of immunological recovery (1,341 vs. 544 CD4+ cells/mm(3) ). The spread of non-B subtypes is increasing throughout the world but their response to treatment is still unclear. PIs and NNRTIs are effective but further tests are needed to allow the more efficient recognition of these viral strains and establish how they should be treated.