The Topic of This Month Vol.22 No.5(No.255)
The HIV/AIDS Surveillance, started in 1984, was carried out from 1989 to March 31, 1999 in compliance with the AIDS Prevention Law. Since April 1, 1999, it has been carried on as a part of the National Epidemiological Surveillance of Infectious Diseases (NESID)(the category IV notifiable infectious diseases) under the Law Concerning the Prevention of Infectious Diseases and Medical Care for Patients of Infections (the new Infectious Diseases Control Law) (see IASR, Vol. 21, No. 7). The following is a summary of the 2000 Annual Report confirmed by the National AIDS Surveillance Committee on April 24, 2001.
1. HIV/AIDS in 2000: HIV-infected persons without AIDS (hereafter abbreviate to HIV cases) newly reported in 2000 totaled at 462 (389 males and 73 females) and AIDS patients at 327 (278 males and 49 females). Concerning the nationality and sex, Japanese males accounted for 73% of both HIV cases and AIDS patients (Fig. 1). The greater part of Japanese cases/patients acquired the infection within the country (80 and 73% of HIV cases and AIDS patients, respectively). Of the modes of infection, heterosexual contacts (37 and 49% of HIV cases and AIDS patients, respectively) and homosexual contacts (47 and 22%, respectively) accounted for higher ratios, while both mother-to-child infections (0.6% of both) and intravenous drug abuse (0.2 and 0.3%, respectively) were less frequent.
2. The trend of incidence from January 1985 through December 2000: The reports of HIV cases and AIDS patients until December 31, 2000 (not including those infected by use of coagulation factor products) totaled at 3,905 and 1,913, respectively, corresponding to 3.087 and 1.512 per 100,000 of the population, respectively. The yearly reports of HIV cases, showing a temporary decrease after the peak in 1992, have again increased since 1996 (Fig. 2). The reports in 2000 were 68 fewer than those in 1999. Nevertheless, it was the second largest number per year till now. The yearly reports of AIDS patients have continuously been increasing except those in 1998; those in 2000 showed an increase of 27 from 1999 (Fig. 2).
An independent national HIV/AIDS study confirmed additional 1,432 HIV cases and 642 AIDS patients due to HIV-contaminated products of coagulation factor as of the end of May 1998. (All cases and patients were Japanese.)
Nationality and sex: The recent increase in HIV cases reflects that of Japanese male cases; Japanese female cases have shown a rapid repetition of increase/decrease during the past 5 years (Fig. 3a, b). Non-Japanese cases showed a slight decrease or kept the same level during the past 5 years (Fig. 3c, d). A sharp increase in AIDS patients is seen among Japanese males, while a little or no increase among Japanese females or either sex of non-Japanese.
Many of non-Japanese HIV cases and AIDS patients are from Southeast Asia, followed by Latin America and sub-Saharan Africa.
Age distribution: The ages of HIV cases reported during the 5 years from 1996 through 2000 in comparison with those reported during the preceding 5 years are shown in Fig. 4. Japanese male cases, with a peak at the age of 25-34, have tended to increase in a wide age range. Japanese female cases at the age of 20-34 and over 45 years are in the increase. In contrast, non-Japanese female cases at the age of 20-24 years markedly decreased. Among AIDS patients of Japanese males, a peak is seen at particularly higher ages, 40-54 years; for other patient groups, peaks are seen at the age of 25-34 years.
Modes of infection: Sexual contacts caused infection in 74% of HIV cases and 69% of AIDS patients. For HIV cases of Japanese males, homosexual contacts have continuously been increasing and doubled in the past 3 years (Fig. 3a). For non-Japanese HIV cases, all modes of infection have slightly been decreasing or maintained the same level (Fig. 3c, d). For Japanese AIDS patients, reports of heterosexual contacts have increased and an increasing tendency of homosexual contacts is seen during the past 4 years. For non-Japanese AIDS patients, repeated increase and decrease in reports of heterosexual contacts have appeared during the past 5 years.
Regions of acquiring infection: Japanese HIV cases acquiring infection within the country and in an unknown region kept increasing until 1999 and then showed a slight decrease in 2000; cases of overseas infection have maintained the same level. In regard to AIDS patients, domestic infection largely increased among Japanese males and females.
AIDS-defining diseases: Ratio of each AIDS-defining disease among Japanese and that among non-Japanese with all reported AIDS patients (1,407 and 506, respectively) as the denominator are similar each other. Pneumocystis carinii pneumonia accounted for the highest ratios, 46 and 42%, candidiasis 23 and 15%, respectively, and wasting syndrome due to HIV 13% in both the nationality groups. There was a difference in number of active tuberculosis cases between the two groups; Japanese cases accounted for 7.2%, while non-Japanese ones twice as high ratio as 13%. Cytomegalovirus infection accounted for a higher proportion among Japanese than non-Japanese patients, 10 and 4.2%, respectively.
Deaths from AIDS: Deaths from AIDS reported before March 31, 1999 under the AIDS Prevention Law totaled at 596, of which 485 were Japanese (445 males and 40 females) and 111 non-Japanese (77 males and 34 females). According to the new Infectious Diseases Control Law enacted in April 1999, reports of case-follow-up data (HIV¨AIDS, alive¨death) are not obliged. Deaths from AIDS reported voluntarily by physicians during April 1, 1999 through December 31, 2000 numbered 83, including 67 Japanese (62 males and five females) and 16 non-Japanese (11 males and five females). Recently, reports of deaths from AIDS among Japanese male and female patients have seemingly been decreasing.
3. HIV-antibody-positive rate among blood donors: The HIV-antibody-positive rate among blood donors has increased year to year, reaching 1.026 per 100,000 donations in 1999 (see p. 124 of this issue). The rate further increased to the highest, 67 per 5,877,971, or 1.140 per 100,000 donations (1.812 for males and 0.167 for females) in 2000 (Fig. 5). Sixty-seven positive cases include three demonstrated only by the nucleic acid amplification test (NAT) (see p. 110 of this issue).
4. HIV counseling and testing at health centers: HIV counseling was made 107,256 times at health centers in 2000, less than half as frequent as those of the largest number achieved in 1992 (251,926). Such was the case in each of the past 4 years. HIV tests conducted at health centers numbered 53,218 in 1998, 48,218 in 1999 and 48,620 in 2000, about half of the frequency shown in 1992 (135,674).
Although slightly decreased in 2000, reports of HIV infection counted the second largest number ever. However, the HIV cases among HIV-antibody not tested could not be counted. To prevent spread of HIV infection, we must keep on more active AIDS prevention programs by enabling everybody to receive counseling and tests for HIV at any time and place that suite ones convenience.