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Background  

South African households are severely affected by human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) but health and economic impacts have not been quantified in controlled cohort studies.  相似文献   
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LR Petersen  ; LS Doll 《Transfusion》1991,31(8):698-703
Transmission of human immunodeficiency virus type 1 (HIV-1) by homologous blood transfusion in the United States (US) is minimized by the deferral of potential donors who are at risk for HIV-1 infection and by the screening of all donations for HIV-1 antibody. HIV-1-seropositive donors at 20 blood centers were studied for information to be used in evaluating the safety of the US blood supply and making recommendations to increase that safety. From June 1988 to August 1989, 829 (0.04%) of 2,192,000 donors were found to be seropositive; 512 were interviewed. Of 388 seropositive men, 56 percent had had sex with men, 10 percent had used drugs intravenously, 8 percent had had sex with intravenous drug users, and 27 percent had no identified risk. Of 124 seropositive women, 58 percent had had sex with men at risk for HIV (81% of whom used drugs intravenously), 5 percent had used drugs intravenously, and 41 percent had no identified risk. Racial and ethnic minorities made up 68 percent of seropositive donors (black, 38%; Hispanic, 30%) and approximately 14 percent of all donors. The 157 persons with no identified risk had demographic characteristics and serologic test results for syphilis and hepatitis B that were more similar to those of HIV-1-seropositive donors with recognized risk than to those of seronegative donors. Three health care worker-blood donors (from an estimated 93,100 health care worker-donors) had infection that was probably acquired occupationally.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Antimicrobial susceptibility testing, auxotyping-serotyping, and plasmid analysis were performed on 41 ocular isolates, 7 nasopharyngeal isolates, and 18 cervical isolates of Neisseria gonorrhoeae obtained during a recent treatment trial of gonococcal ophthalmia neonatorum in Nairobi, Kenya. Fourteen distinct serovar-auxotype patterns were observed with IB-1/Pro-strains which accounted for 59% of the isolates. Infection with multiple types of gonococci appeared to occur in 22% of the mothers since 4 of 18 paired maternal cervical and neonatal ocular isolates had mismatched serovar-auxotype patterns. Among 10 treatment failure isolates only 1 had a mismatched serovar-auxotype pattern. Six (15%) of the ocular isolates were penicillinase-producing N. gonorrhoeae (PPNG). Five had the 4.4-megadalton (Md) beta-lactamase plasmid and one had the 3.2-Md beta-lactamase plasmid. The 24.5-Md plasmid was found in 5 of 6 PPNG strains and in 8 of 35 non-PPNG strains (P less than 0.02). For most antimicrobial agents, PPNG and non-PPNG strains showed similar patterns of susceptibility. Ceftriaxone was the most active of the antibiotics tested, with all strains having an MIC less than or equal to 0.06 mg/liter. Among non-PPNG strains, 15 (43%) had a penicillin MIC greater than or equal to 2 mg/liter and were considered intrinsically resistant to penicillin. Overall, non-PPNG intrinsically resistant strains had greater resistance to other antibiotics than did non-intrinsically resistant strains (P less than or equal to 0.006). The Mtr phenotype was found in 53% of these strains.  相似文献   
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