HIV in Japan: Epidemiologic puzzles and ethnographic explanations

Associations between Social Capital and Self-Rated Health among Men Who Have Sex with Men in Japan

Men who have sex with men (MSM) are significantly more likely to report poor health compared to the general population in Japan and internationally. Social capital has been observed as an important component of positive health and well-being outcomes among MSM. However, there is limited research investigating how alter sexuality (possessors of actual resources embedded in social capital networks) mitigates health outcomes. In an online survey of 1564 MSM in Japan, we investigated social correlates of poor self-rated health among MSM, including MSM and heterosexual social networks. Multiple logistic regression revealed that poor health was associated with older age, lower education, and part-time and unemployment. Poor health was inversely correlated with bisexual behavior and high MSM or heterosexual social capital. In order to decrease health disparities among MSM in Japan, interventions focusing on increasing social capital among deprived groups, such as those with lower socio-economic status, older MSM, and those whose sex partners are exclusively male, may be effective.

Elimination of HIV transmission in Japanese MSM with combination interventions

Background

Japan has a concentrated HIV epidemic, with the majority of transmission among men who have sex with men (MSM). This study aimed to explore the effect of behavioral and biomedical interventions on the HIV epidemic and forecast the time required to eliminate HIV transmission among Japanese MSM.

Methods

A deterministic compartmental model was built to estimate and forecast the HIV epidemic among Japanese MSM from 2010 to 2050. Elimination of HIV transmission among MSM was defined as incidence less than 1/1000 person-years. The time required for eliminating HIV transmission under different scenarios was calculated.

Findings

Under the current policies, HIV transmission cannot be eliminated by 2050. Both behavioral and biomedical interventions can achieve elimination of HIV among MSM by 2050 with annual number of sexual partners among high-risk MSM less than 9, or with condom use rate above 65%, or with testing and treatment rate above 80%, or with more than 10% PrEP coverage rate. Under comprehensive interventions, HIV elimination will be achieved in 2032, 2025 and 2024 using weak, moderate and strong intervention combinations, respectively.

Interpretation

Both behavioural and biomedical interventions can achieve elimination of HIV among MSM by 2050, but comprehensive interventions can accelerate the realization of this goal with higher feasibility.

Funding

This study was funded by a Health and Labor Sciences Research Grant (Research on HIV/AIDS) from The Ministry of Health Labour and Welfare (21HB0701) and National Natural Science Foundation of China (No. 81773543 and 81973150), and the KC Wong Education Foundation.

In Vitro Antiviral Activity of Mentha cordifolia Plant Extract in HIV-1 Latently Infected Cells Using an Established Human Cell Line

Emergence of drug resistance demands new therapeutic strategies against the human immunodeficiency virus (HIV). Currently, there is an increasing research focus on targeting gene expression-the crucial step wherein new viruses and new viral strains are amplified. Moreover, natural products are also being considered as potential candidates for new antivirals. We screened the extract obtained from a Philippine medicinal plant, Mentha cordifolia (Mc). In this study, we demonstrated that Mc ammonium sulfate extract has antiretroviral activity against HIV. HIV-1 latently infected cells (OM10.1) were pretreated with Mc extract and activated with TNFα. In treated cells, viral replication was inhibited in both cell culture supernatant and whole cell lysates. The level of viral production, as measured by the viral p24 protein concentration, was very much inhibited under noncytotoxic concentrations to the similar level without addition of TNFα. Luciferase assays, however, showed that Mc does not inhibit the HIV-1 long terminal repeat-driven gene expression. IκBα degradation and p65 nuclear translocation was also not affected as visualized through Western blot and immunofluorescence. These observations demonstrated that Mc possessed an antiviral component against HIV-1 and warrant further work to explore its target of action at a later step of gene expression. Our study introduces a potential source of a lead compound that targets steps in the HIV life cycle.

Associations Between Social Capital and HIV Risk-Taking Behaviors Among Men Who Have Sex with Men in Japan

Social capital has been positively associated with reduced HIV risk. However, few studies have investigated if associations vary between men who have sex with men (MSM) or heterosexual alters (possessors of actual resources embedded within social capital networks) and HIV risk-taking behaviors. In a cross-sectional survey of 1564 MSM in Greater Tokyo, we investigated whether social capital ascertained from MSM or heterosexual alters influenced HIV risk-taking behaviors (i.e., consistent condom use and lifetime HIV testing). Multiple logistic regression revealed that MSM with high levels of social capital from heterosexual networks were twice as likely to report consistent condom use with casual male partners, while MSM who reported high levels of social capital from MSM networks were over twice as likely to have tested for HIV yet were half as likely to use condoms consistently with regular male partners. Associations between MSM, social capital, and HIV testing indicate the potential for integrating social capital enhancement programs into current HIV interventions.

Prevalence and correlates of lifetime and recent HIV testing among men who have sex with men (MSM) who use mobile geo-social networking applications in Greater Tokyo

Men who have sex with men (MSM) are disproportionately burdened by the human immunodeficiency virus (HIV), accounting for 78% of all Japanese male HIV cases in 2016. Over 30% of newly identified HIV infections in Japan are diagnosed as AIDS annually, suggesting a large proportion of people living with HIV were unaware of their own infection status. An estimated two-thirds of Japanese men who have sex with men (MSM) are not attached to the gay community, and previous studies have largely sampled gay venues, thus, previous studies have likely failed to reach many men in this population. This study therefore examined HIV testing prevalence and correlates among MSM in Greater Tokyo who use gay mobile geo-social networking applications (gay mobile apps), which have been found to increase access to MSM not traditionally accessible through venue-based surveys. Among a sample of 1657 MSM recruited through advertisements on gay mobile apps, the prevalence of lifetime and six-monthly HIV testing was 72.8% and 29.7% respectively. In multiple regression analysis, higher lifetime HIV testing was associated with older age, education, HIV knowledge, anal intercourse with regular and casual male partners, and gay venue attendance. Testing was negatively associated with regular male partner condom use, marriage, residing outside central Tokyo and having both male and female partners. These results indicated that MSM who use gay mobile apps in Greater Tokyo do not meet the CDC yearly testing recommendations for high risk populations. Considering limited HIV prevention funding in Japan for MSM, moderate lifetime and recent testing, and the large number of gay mobile app users, utilization of popular gay mobile apps to promote nearby HIV testing facilities may be an effective prevention policy to target non-community attached MSM, particularly at-risk youth and individuals at risk of sudden-onset AIDS.

HIV/AIDS in Japan: Route and Age of Infection that Shaped the Epidemics in 1987-2016

In Japan, HIV infection is classified as "HIV" or "AIDS" depending upon whether the infection was detected before or after the development of AIDS. In male homosexuals, in the plot of the number of "AIDS" notified annually versus the that of "HIV" notified annually, the plot fell on a straight line with a slope close to 1. When the number of "HIV" no longer increased, that of "AIDS" also stopped increasing. The number of "HIV" notified in one region or age group was correlated with that of other regions or age groups, respectively. However, no such correlation was observed among male heterosexuals. "HIV" was detected more frequently among male homosexuals and females than among male heterosexuals. The rate of "AIDS" detection increased with age in all infection categories. Our analysis, supported by findings of other studies, suggested that the higher rate of "HIV" detection among male homosexuals and females was attributed to the increased risk of receptive sexual intercourse, while the higher rate of "AIDS" detection among the elderly people was attributed to immunological senescence.

Body/Selves and Beyond: Men's Narratives of Sexual Behavior on PrEP

Although pre-exposure prophylaxis (PrEP) has dramatically impacted HIV prevention, deep engagement with PrEP-takers' own accounts of their sexual behavior is still rare. We report findings from semi-structured interviews with male participants of the US PrEP Demonstration Project. In their narratives, interviewees variously foregrounded their individual selves, interactions with sexual partners, and the biopolitical and historical context of their lives. PrEP served to discursively integrate the multiple selves populating these stories. We argue that medical anthropological notions can help make sense of men's accounts, and PrEP's role in them, advancing a holistic conception of personhood that includes but transcends concern with HIV.

HIV Pre-Exposure Prophylaxis and Postexposure Prophylaxis in Japan: Context of Use and Directions for Future Research and Action

Biomedical HIV prevention strategies are playing an increasingly prominent role in addressing HIV epidemics globally, but little is known about their use in Japan, where persistent HIV disparities and a recently stable, but not declining, national epidemic indicate the need for evolving approaches. We conducted an ethnographic study to determine the context of pre-exposure prophylaxis (PrEP) and postexposure prophylaxis (PEP) use and to identify directions for future research and action in Japan. We used data from observational fieldwork in the Kansai region and Tokyo Metropolitan Area (n = 178 persons observed), qualitative interviews (n = 32), documents and web-based data sources (n = 321), and email correspondences (n = 9) in the period 2013-2016. Drug approvals by Japan's regulatory agencies, insurance coverage for medications, and policies by healthcare institutions and government agencies were the main factors affecting PrEP and PEP legality, use, and awareness. Awareness and the observable presence of PrEP and PEP were very limited, particularly at the community level. PrEP and PEP held appeal for Japanese scientists and activists, and for study participants who represented various other stakeholder groups; however, significant concerns prevented open endorsements. Japanese health officials should prioritize a national discussion, weigh empirical evidence, and strongly consider formal approval of antiretroviral (ARV) medications for use in PrEP and both occupational and nonoccupational PEP. Once approved, social marketing campaigns can be used to advertise widely and increase awareness. Future research would benefit from theoretical grounding in a diffusion of innovations framework. These findings can inform current and future ARV-based prevention strategies at a critical time in the international conversation.