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An outbreak of enterovirus 71 infection in Taiwan in 1998 killed 78 people and made over 120,000 people sick. Normally, this virus can cause blisters on the hands, feet and mouth, but is usually not life-threatening. In the Taiwan outbreak, 405 people had severe disease, and most were five years old or younger. Ninety-one percent of the deaths were children five years old or younger. Eighty-three percent of the patients who died had fluid in their lungs or blood in their lungs. Ninety-two percent had been infected with enterovirus 71.

Zidovudine, formerly called AZT, has been found to slow the clinical progression of AIDS and inhibit the cellular replication of HIV (human immunodeficiency virus, which causes AIDS). Unfortunately, the benefits of zidovudine treatment are not without significant risk of side effects, such as anemia (diminished population of red blood cells), and neutropenia (fewer white blood cells). These side effects can severely compromise the health status of patients with AIDS. The present standard dose of zidovudine is 1,500 milligrams (mg) per day. This clinical trial documents the effects of reduced dose levels of zidovudine in patients with AIDS. Individuals who had experienced their first bout of Pneumocystis carinii pneumonia at least two weeks earlier were eligible for entrance into the study. However, patients who had previously been treated with zidovudine or had experienced multiple episodes of Pneumocystis carinii pneumonia, or Kaposi's sarcoma (a lung tumor that affects AIDS patients) were ineligible. The participants (524) were equally divided into two groups: the standard-treatment group received 250 mg of zidovudine every 4 hours; and the reduced-treatment group was given 200 mg of zidovudine every 4 hours for four weeks, when the dose was reduced to 100 mg of zidovudine every 4 hours. The patients were followed for a period of up to 25.6 months. Blood specimens were examined for the presence of HIV antigen (a protein associated with HIV infection), and the number of CD4-T lymphocytes (a specific class of white blood cells that decreases in number as AIDS worsens). The survival rates at 18 months were 52 percent for the standard-treatment group and 63 percent for the reduced-treatment group. The percentage of patients who developed opportunistic infections was the same in both groups (82 percent). Zidovudine transiently improved the CD4-T lymphocyte count in both treatment groups. Patients treated with the reduced dose strategy experienced significantly less anemia and neutropenia. The findings demonstrate that reducing the daily dose of zidovudine provides effective treatment for AIDS patients, and is associated with a reduction of some side effects. (Consumer Summary produced by Reliance Medical Information, Inc.)

The health threat posed by HIV-1 infection (human immunodeficiency virus, type 1, which causes AIDS) may have reduced public awareness of another major disease of homosexual men, hepatitis B virus (HBV) infection. Receptive anal intercourse is considered to be the principle route for acquisition of HIV-1, while HBV is thought to spread as a result of several kinds of homosexual contact. To better understand the transmission efficiency (how effectively they are transmitted) of the two diseases, three groups of homosexual and bisexual men were studied over a 2.5-year period. Members of group 1 (776 men) were seronegative for HIV-1 (did not have evidence of the virus in their blood) at baseline; group 2 (333 men, some overlap with group 1), was seronegative for HBV (did not test positive for antibody to hepatitis B core antigen, or positive for hepatitis B surface antigen); and men in group 3 (314, a subgroup of the first two groups) were seronegative for both diseases. Seroconversion rates (rates of testing positive for these diseases) were evaluated at six-month intervals, and data regarding sexual practices were obtained. Results showed that the risk of seroconversion to both HIV-1 and HBV was greater during the first year, especially during the first six months. The proportion of men who seroconverted to HBV during the study period was 19.8 percent, and for HIV-1, 7.8 percent. This was true, even though the prevalence of hepatitis B carriers was much lower than that of HIV-1 carriers. Participating in anal intercourse was a risk factor for both infections. A higher proportion of HIV-1 seroconverters (89 percent) had engaged in receptive anal intercourse within six months of seroconversion, while this was true for 71 percent of HBV seroconverters. HBV seroconversion, on the other hand, was more highly related to insertive anal intercourse, suggesting that the urethra may be a route of infection. An independent risk factor for HBV seroconversion was prior or subsequent infection with HIV-1. The concept of relative sexual transmission efficiency (RSTE) of HBV, as compared with HIV-1, is defined, and calculated to be 8.6. The data support the use of immunization against HBV and the use of condoms during homosexual intercourse. (Consumer Summary produced by Reliance Medical Information, Inc.)