The topic of This Month Vol.38 No.9(No.451)

HIV/AIDS in Japan, 2016

(IASR Vol. 38 p177-178: September, 2017)

HIV/AIDS surveillance in Japan started in 1984.  It was conducted under the AIDS Prevention Law from 1989 to March 1999 and since April 1999, has been operating under the Infectious Diseases Control Law.  Physicians are required to notify all the diagnosed cases (see for the reporting criteria).  The data in this article were derived from the annual report of the National AIDS Surveillance Committee for the year 2016 (reported by the Tuberculosis and Infectious Diseases Control Division, the Ministry of Health, Labour and Welfare (MHLW),  HIV/AIDS cases are classified into two categories: as an “HIV case” if HIV infection was detected before clinical manifestation of AIDS, and as an “AIDS case” if the infection was detected after manifestation of AIDS symptoms*.

The cumulative number of reported HIV/AIDS cases (excluding coagulating agent-related cases) from 1985-2016 was 18,920 for HIV (16,532 males; 2,388 females) and 8,523 for AIDS (7,747 males; 776 females) (Fig. 1). According to the National Survey of Blood Coagulation Abnormality Cases (as of 31 May 2016), the cumulative number of the coagulating agent-related HIV infected cases was 1,439, including 711 deceased cases.

Globally, an estimated 36.7 million people are currently HIV-infected. Every year, 1.8 million acquire HIV infection and an estimated 1 million infected people die of the infection (according to the UNAIDS Fact Sheet JULY 2017,

1. HIV/AIDS cases reported in Japan in 2016
Since 2007, around 1,500 HIV/AIDS cases have been reported annually (range: 1,002-1,126 for HIV and 418-484 for AIDS). In 2016, 1,011 HIV (965 males; 46 females) and 437 AIDS (415 males; 22 females) cases were reported (Fig. 2). Among the 1,011 HIV cases, 885 were Japanese (857 males; 28 females) and 126 were non-Japanese (108 males; 18 females). Thus, Japanese males occupied 85% of the total HIV cases (857/1,011) and 86% of the total AIDS cases (376/437). Men who have sex with men (MSM), including bisexual contacts, made up 73% (735/1,011) of all HIV cases and 78% (669/857) of all Japanese male HIV cases (Fig. 3, Fig.), and the majority were in their 20’s to 40’s (Fig. 4). Males infected through heterosexual contact made up 14% (137/1,011) of all HIV cases and 14% (117/857) of all HIV cases of Japanese nationality. Among Japanese female HIV cases, the route of transmission was recorded as heterosexual contact for 79% (22/28) and other/unknown for the remaining 21% (6/28) of the cases. No case attributed to congenital infection was reported in 2016. One Japanese male case attributed to infection through intravenous drug use (IDU) was reported in 2016; except for 2013 when no case was reported, 1-5 IDU cases have been reported every year since 2001.

Suspected place of infection: Until 1992, majority of infections were acquired abroad, but since then most infections have been acquired in Japan. In 2016, 83% of all HIV cases (838/1,011) and 88% of HIV cases with Japanese nationality (783/885) were infected in Japan.

Place of notification by physicians: The Kanto-Koshinetsu area (514 HIV and 185 AIDS cases), which includes Tokyo, and the Kinki area (185 HIV and 77 AIDS cases) reported the largest number of HIV/AIDS cases. Based on the number of notifications per 100,000 population, the top ten highest prefectures for both HIV and AIDS included prefectures in the Kyushu and the Chugoku-Shikoku areas (Table).

2. HIV antibody positivity rate among blood donors
In 2016, among 4,841,601 donated blood specimens, 48 were HIV positive (44 males; 4 females), which corresponds to 0.991 HIV positive specimens (male: 1.261; female: 0.296) per 100,000 blood donations (Fig. 5).

3. HIV antibody tests and consultations provided by local governments
The number of people receiving HIV tests at health centers and other facilities managed by local governments was 118,132 in 2016, which was slightly lower than that in 2015 (128,241) (Fig. 6). Among those tested, 421 were HIV positive in 2016 (463 positives in 2015), corresponding to 0.36% positivity (0.36% in 2015). While HIV positivity among specimens tested in health centers was 0.28% (248/88,773), the positivity among specimens tested in facilities other than health centers was 0.59% (174/29,359), considerably higher than in the health centers. The number of people who accessed counselling services provided by the local governments was 119,382 in 2016, which was slightly lower than that in 2015 (135,282).

The number of HIV/AIDS cases reported in 2016 was 1,448 (1,434 in 2015). About 30% of the HIV/AIDS cases in 2016 were detected after development of AIDS, suggesting that many HIV-infected persons were unaware of their own HIV infection. For early diagnosis of HIV infection, epidemiological characteristics of HIV/AIDS (e.g., high HIV detection rate among those in their 20’s and increasing notifications of AIDS cases among those aged 60 years or older) should be recognized, and the central and local governments should establish a policy for early detection of HIV infection and develop effective strategies for preventing spread of HIV while promoting early treatment. Effective preventive measures include making HIV testing and medical consultations more accessible in time and place for those such as MSM, adolescents, commercial sex workers, and their clients. It is important to consider human rights and coordinate with key stakeholders (e.g. healthcare workers, non-governmental organizations, and those in the education sector).

The national HIV/AIDS control policy should include enhancing the understanding of the HIV/AIDS trends in Japan, raising public awareness, and development of early diagnosis and therapeutic interventions. The national policy should be such that it also contributes to global HIV/AIDS control. While effective in preventing progression to AIDS, anti-HIV chemotherapy necessitates life-long treatment as it does not eliminate HIV from the patients. In addition, life-long treatment is associated with occurrence of drug-resistant HIV variants and serious pathological conditions due to latent infection under antiretroviral therapy, such as neurocognitive dysfunction, osteoporosis, and cardiovascular disorder, which are new challenges for HIV/AIDS management.

*HIV surveillance in Japan counts a case as an “HIV case” if a case is laboratory diagnosed with HIV infection (but without manifestation of AIDS symptoms), and as an “AIDS case” if a case is laboratory diagnosed with HIV infection and manifests AIDS symptoms at the time of initial diagnosis and report. An HIV infected case once registered as an “HIV case” is not registered as an “AIDS case” even if he/she subsequently develops AIDS.

Copyright 1998 National Institute of Infectious Diseases, Japan