Serum samples collected from patients with a wide variety of diseases from African and other countries were tested for antibodies to the human spumaretrovirus (HSRV). A spumaviral env-specific ELISA was employed as screening test. Out of 3020 human sera screened, 106 were found to be positive (3.2%). While the majority of patients' sera from Europe (1581) were negative, 26 were positive (1.6%). Sera from healthy adult blood donors (609), from patients with multiple sclerosis (48), Graves' disease (45), and chronic fatigue syndrome (41) were negative or showed a very low prevalence for spumaviral env antibodies. A higher percentage of seropositives (6.3%) were found among 1338 African patients from Tanzania, Kenya, and Gabon. Out of 1180 patients from Tanzania, 708 suffered from tumors, 75 from AIDS, and 128 had gynecological problems; 51 of the Tanzanian patients were HSRV seropositive (4.3%). A particularly high percentage of 16.6% seropositives were identified among nasopharyngeal carcinoma patients (NPC) from Kenya and Tanzania consistent with results reported 10 years ago. However, 20 nasopharyngeal carcinoma patients from Malaysia were HSRV-seronegative. In selected cases, sera from seropositive individuals were reacted with proteins from HSRV-infected cells in vitro. HSRV env- and gag-specific antibodies were specifically detected by these sera in Western blots. The results indicate spumavirus infections in human patients with various diseases at a relatively low prevalence worldwide; in African patients, however, the prevalence of spumavirus infections is markedly higher.

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A comparison of various cultural methods for use with microcolony and direct fluorescent-antibody (FA) techniques to detect salmonella was conducted using 102 naturally contaminated samples. The methods were: (a) a 27-h microcolony technique, (b) a 51-h selenite-F FA microcolony technique, (c) a 51-h tetrathionate brilliant green FA microcolony technique, and (d) a 53-h FA technique from a broth enrichment. All were compared to an F.D.A. approved modification of the AOAC method. The 51-h FA microcolony technique, which employed tetrathionate brilliant green broth and brilliant green agar plates, produced 4.9% false-positives and no false-negatives, and produced the greatest frequency of salmonellae detection.