HIV-1 positive patients from Tanzanian villages near Shirati were examined for urinary excretion of the human polyomaviruses JC and BK using the polymerase chain reaction (PCR). BK virus (BKV) was detected in 11 of 23 individuals tested. The BKV DNA sequences were all closely related to prototype Gardner strain and BKV (DUN). In contrast, a new type of JCV, termed Type 3 [or JCV (Shi)], was identified in seven of these same 23 individuals by comparison with Type 1 and Type 2 sequences of the VP1/intergenic/T antigen region of U.S., European and Asian strains. This suggests that JCV and BKV, although closely related, have different evolutionary histories within the African population. The six BKV regulatory regions amplified all showed the archetypal configuration. However, two of the seven JCV regulatory regions showed rearrangements: a small deletion and an inverted repeat. JCV causes a fatal demyelinating disease, progressive multifocal leukoencephalopathy (PML), in about 5% of AIDS patients in Europe and the U.S.A., but only one case has been reported in Africa. Our results suggest that this rarity of PML is not due to the absence of JCV in the African population.

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Sera of patients with breast cancer, of healthy women from the United States, East India, East Africa, and China, and of healthy women of American and Parsi families in which breast cancer occurred in several family members were assayed for levels of antibody reactive with the murine mammary tumor virus (MuMTV) by an enzyme-linked immunosorbent assay. Increased levels of antibody to MuMTV (absorbance -0.4) were found in sera of 18.6% ofAmerican patients with breast cancer and of 2.8% of healthy American women and in 38% of patients from India and 61.9% from East Africa (healthy, 26.9%). In contrast, antibody reactive with MuMTV was found in <5 of women with breast cancer from mainland China (healthy Chinese, 5.0%). Differences in serum MuMTV antibody levels between breast cancer patients in the four groups were found to be significant (P < 0.0001). Studies of two families from the United States and of one Parsi family from India with genetic propensity to breast cancer showed that high levels ofantibody to MuMTV were found in 33%, 71%, and 23% of healthy family members, respectively. The antibody to MuMTV was readily absorbed with purified MuMTV and gp52. In contrast, fetal calf serum, murine type C retroviruses, or erythrocytes from various species failed to absorb the antibody. A relationship between human breast cancer and murine mammary tumor virus (MuMTV) has been suggested from several observations. RNA partially homologous to the MuMTV genome was identified in human breast cancer tissue (1). Lymphocytes from individuals with breast cancer were shown to proliferate after stimulation by MuMTV (2, 3). Sera from breast cancer patients decreased the infectivitity of MuMTV in mice (4), suggesting the presence of antibodies against the virus. More recently, using immunoperoxidase staining, Mesa-Tejada et al. (5) found that antigen reacting with antibody to the envelope glycoprotein of MuMTV (gp52) could be detected in breast cancer tissue. Ohno et al. (6) have now demonstrated that this crossreactivity is directed to the protein moiety ofgp52 and not the carbohydrate.In prior studies using a virolytic assay with complement and antibody, we found that antibodies reactive with MuMTV are present in sera of approximately 20% of American women with breast cancer (7). Sera of age-matched healthy women and of patients with other cancers had such antibodies in lower frequency. We developed a method to detect these antibodies directly by using MuMTV and an enzyme-linked immunosorbent assay (ELISA) (8). With this method also we found that sera of approximately 25% of American women with breast cancer had antibodies to MuMTV. Approximately 10% ofwomen with benign cystic disease of the breast also had such antibodies in their sera (8). Reactivity was inhibited by the membrane proteins of MuMTV (gp52 and gp34) but not by the core antigen (p28) (9).We now report results on the specificity of the human antibody for MuMTV, the geographic distribution of the antibody in breast cancer patients, and analyses of families in...

Abstract. Sera from 516 participants enrolled in a population-based cross-sectional study in northwest Tanzania were tested for antibodies to hepatitis C virus (HCV). The mean age of study subjects was 29 years (range ϭ 16-49 years); 43% were men, 6% reported a history of blood transfusion, and 4% were infected with human immunodeficiency virus-1 (HIV-1). Although 53 of 516 sera (10.3%, 95% confidence interval [CI] ϭ 7.8-13.2%) were repeatedly reactive by a third-generation enzyme immunoassay (EIA-3), only 6 of the 53 were positive when tested with a thirdgeneration recombinant immunoblot assay (confirmed HCV seroprevalence ϭ 1.2%, 95% CI ϭ 0.4-2.5%). The positive predictive value of the HCV EIA-3 in this population was 18.8% (95% CI ϭ 7.0-36.4%). False positivity was not correlated with EIA-3 optical density values, age, sex, infection with HIV-1, or a history of blood transfusion, but it was marginally associated with increased serum IgG levels. We conclude that the prevalence of HCV is low in this region and that the HCV EIA-3 has a higher false-positivity rate in this population than has been reported among U.S. blood donors.Hepatitis C virus (HCV) is the major etiologic agent of post-transfusional hepatitis worldwide 1 and may also be an important cause of community acquired non-A, non-B hepatitis in certain parts of Africa. 2,3 Infection with HCV is usually asymptomatic, but may result in chronic hepatitis with progression to cirrhosis and hepatocellular carcinoma. 4,5 Assays for the detection of antibodies against HCV proteins were developed soon after the viral genome was cloned in 1989. 6 An enzyme immunoassay (EIA) represented an important advance in reducing HCV transmission through blood transfusion. Supplemental tests for detecting antibodies to HCV, such as the recombinant immunoblot assay (RIBA), have been developed to confirm reactivity detected by the EIA. 7 Studies of volunteer blood donors and general populations have shown considerable geographic variation in HCV seroprevalence:8 0.5-1.5% in western Europe, northern Europe, North America, and Australia; 1.5-2.5% in Japan and the Mediterranean region; and as high as 14% in Egypt. In sub-Saharan Africa, data on the prevalence of HCV are limited and the extent of HCV infection remains unknown in most countries. In this study, we estimated the seroprevalence of HCV in a population-based cross-sectional study in northwest Tanzania. METHODSDuring 1989 and 1990, a population-based study was conducted to estimate the prevalence of human immunodeficiency virus (HIV) in northwest Tanzania. The protocol for this study was approved by the appropriate review committees of the Tanzanian Ministry of Health and the National Cancer Institute. The study methods have been described elsewhere. 9 Briefly, the target population consisted of people living in rural, peri-urban (mainly subsistence farmers and their families), and urban areas (commercial workers). Subjects 15-49 years of age were randomly selected from household rosters supplied by the local governmen...