Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

More than 30% of the general adult populations of some East and Central African cities are infected with HIV. Transmission in Africa South of the Sahara, as opposed to transmission in North America and Europe, occurs primarily through heterosexual intercourse. Some have theorized that infection with sexually transmitted diseases (STD) may facilitate HIV transmission. The high prevalence of STDs in many parts of Africa could therefore play a major role in the rapid heterosexual spread of HIV on the continent. The authors investigated the cofactor effect of genital ulcer disease (GUD) on the risk of HIV transmission during a single heterosexual exposure. Observed risk ratios are expected to be much smaller than per-exposure cofactor effects and to decrease as the observation period lengthens. Data were reanalyzed from longitudinal studies of female prostitutes and men in Nairobi to make rough estimates of the cofactor effects of GUD. The calculations are, however, subject to several caveats and have wide margins of error. The analysis nonetheless suggests that the data are consistent with GUD increasing the risk of male to female transmission by a factor of 10-50, and of female to male transmission by a factor of 50-300. These estimates indicate that GUD may be responsible for a large proportion of heterosexually acquired HIV infections in sub-Saharan Africa, supporting the potential role of STD control as an effective intervention strategy against HIV.
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PMID:The cofactor effect of genital ulcers on the per-exposure risk of HIV transmission in sub-Saharan Africa. 786 74

The purpose of this study was to determine if Mycobacterium leprae is an opportunistic pathogen in immunosuppressed subjects with HIV infection. Ninety six leprosy patients at Infectious Diseases Hospital (IDH), Nairobi were screened for, HIV-1 antibody between January 1991 and June 1992. The patients included 15 who were diagnosed during the study period and 81 who were previously diagnosed and were on anti-leprosy treatment. Blood was screened for HIV antibody by first ELISA and double positive samples were confirmed by a second ELISA. The HIV seronegative patients were re-tested serologically every 3 months. Smears from skin slits were used to determine bacterial index and the patients were classified according to criteria described by Ridley and Jopling. The patients were re-assessed clinically monthly. The mean age of the patients was 40 years and ranged from 13 to 78 years. Forty seven percent had paucibacillary and 53% had multibacillary leprosy. The HIV seroprevalence was 8% in previously diagnosed patients and zero in the newly diagnosed patients. There were no changes in clinical spectrum in HIV seropositive patients during follow up period; neither reversal reactions nor erythema nodosum leprosum were observed. The study suggests that M. leprae may not be an opportunistic pathogen in immunosuppressed subjects with HIV infection.
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PMID:Human immunodeficiency virus- 1 in leprosy patients attending Kenyatta National Hospital, Nairobi. 786 37

From a cohort of female sex workers in Nairobi, Kenya, 163 women were observed to seroconvert to human immunodeficiency virus type 1 (HIV-1) and followed to study progression to HIV-1-related disease. The effect of several covariables on disease progression was studied using a Weibull proportional hazards model. The Weibull survival model was fitted to the observed incubation times. Estimates of the median duration to CDC stage IV-A and IV-C disease were 3.5 and 4.4 years, respectively. Condom use before seroconversion was associated with a reduced risk of CDC stage IV-A disease (relative risk = .64, P < .05). The incubation time of HIV-1-related disease is extremely short in this population.
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PMID:Rapid progression to disease in African sex workers with human immunodeficiency virus type 1 infection. 864 38

The AIDS epidemic is a rapidly growing problem in Nairobi, where the seroprevalence in pregnant women increased from 4% in 1988 to over 10% in 1991. 22 HIV-1-seropositive pregnant women and 1 HIV-1-infected baby (K88) attending the Pumwani Maternity Hospital of Nairobi between 1990 and 1992 were studied as part of a cohort study of maternal risk factors in mother-to-child transmission. A 250-base pair (bp) fragment of the env gene encoding C2V3 was amplified mostly from DNA isolated from primary peripheral blood mononuclear cells and subsequently sequenced. The 23 newly determined HIV env sequences were aligned with 23 previously known sequences of HIV-1 isolates of diverse geographical origin and the sequence of the HIV-1-related chimpanzee isolate SIVcpz-gab, on the basis of primary structure. Distance calculation, tree construction, and bootstrap analysis were realized with the software package TREECON. In the tree, 8 major branches could be observed containing sequences representative of 8 different subtypes A, B, C, D, E, F, G, and H, besides the outlier group O. 19 of 23 Kenyan isolates clustered with D687, Z321, U455, and SF170, which were members of genetic subtype A. Phylogenetic analyses favored positioning of K976 as a divergent A subtype strain. For 4 strains (K29, K88, K98, and K112) the subtype A classification based on the gag gene was also observed on the basis of phylogenetic analysis of the C2V3 coding part of the env gene. The predicted amino acid sequence of the V3 region for these strains was also presented. The finding that among 23 HIV-1 isolates collected in Nairobi, 19 were classified in subtype A versus 3 in subtype D, together with a much larger variation between subtype A strains as compared to subtype D strains, suggests an earlier introduction of a subtype A strain, multiple introductions of subtype A strains, and/or faster diversification of subtype A strains as compared to subtype D strains.
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PMID:Genetic variability of HIV type 1 in Kenya. 788 13

In November 1993, WHO and the UK Department of Health cosponsored a meeting at which the participants addressed the need for women-controlled methods of preventing HIV infection. They called for animal studies to develop vaginal microbicides active against HIV which, in an ideal situation, the women could use without their sexual partners' knowledge. Ideally, any new product would also prevent transmission of other sexually transmitted diseases (STDs). They did caution, however, that the use of such microbicides should not replace, but complement other methods to prevent sexual transmission of HIV. They recommended also that appropriate clinical trials testing the safety and efficacy of the product should also take place. Participants called for WHO to develop the prototype protocols for phase I-III trials of vaginal microbicides. Some spermicides (nonionic detergents or surfactants) provide protection against some STDs (gonorrhea and chlamydial infections) and, in vitro, destroy HIV. Yet, they tend to irritate vaginal mucosa, facilitating HIV transmission. The likelihood of vaginal irritation increases with frequency of use and with doses. Women may not have symptoms indicating that they have spermicide-induced mucosal lesions. A study in Nairobi suggests that use of a sponge impregnated with high dose nonoxynol-9 increased the probability of HIV seroconversion. Lower doses of nonoxynol-9 had a protective effect against HIV seroconversion in studies in Cameroon and Zambia. In all these studies, however, there were sizable methodological limitations. The risk/benefit ratio for individuals using low to moderate doses of spermicides is not clear. Another consideration in that prevention of STDs, significant risk factors for HIV transmission, would reduce the spread of HIV.
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PMID:Boost for vaginal microbicides against HIV. 790 43

The control of sexually transmitted diseases (STDs) is vital to combat AIDS in developing countries. The 1993 World Development Report showed the cost effectiveness of STD control per healthy life-year saved. A meeting of the Network of AIDS Researchers in East and Southern Africa was held on this issue in Mwanza, Tanzania, attended by 20 experts from 5 countries in the region. The World Health Organization recommends that STDs should be managed without laboratory tests, at the primary health care level in developing countries, using drugs of proven local efficacy. In Africa, this policy has been implemented only in Zimbabwe, but without a striking fall in STDs, since in 1991 STDs were responsible for over 20% of visits by adults at primary health care clinics in Harare. A contact-tracing study in Harare indicated that only 20 contacts were found after 3 months' work by 6 staff members. Asymptomatic STDs in women have hampered STD control, but a community study from Mwanza has also shown that 6% of men were infected with gonorrhea or chlamydia and 90% had no symptoms. A WHO risk-assessment protocol is being evaluated in Mwanza among women with vaginal discharge. A controlled trial of mass treatment for gonorrhoea, chlamydia infection, chancroid, and syphilis is to start in Uganda early in 1994 in a community where the incidence of HIV has remained static at 2% per annum in the general adult population (over 6% in young women) despite intensive education campaigns. Even when symptoms are present, most patients seek unofficial treatment in Africa. Increasing antimicrobial resistance among sexually transmitted pathogens in Africa makes STD treatment more expensive. The introduction of user charges in Nairobi led to a sudden fall in attendances at the main STD clinic and in other countries in the region. The treatment of the STDs prevents future infections, thus STD treatment should be free with the help of international donors.
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PMID:STD research in Africa. 790 91

The authors interviewed 675 male and female adolescents aged 14-19 years of mean age 18.2 attending the adolescent antenatal clinic of Kenyatta National Hospital and the Special STD and Skin Disease Clinic in Nairobi between April 1, 1991 and July 31, 1991. The interviews were conducted to determine participants level of awareness on sexually transmitted diseases (STD), HIV infection, AIDS, and contraception relating to their sexual and contraception behaviors. The adolescents comprised 27.6% of clinic attendees; 52.9% were male, 56.5% of males and 77.8% of females were not formally employed and some were students. Respondents mentioned being aware of only three STDs in the following proportions: 70.4% gonorrhea, 56.5% syphilis, and 54.3% AIDS. 76.6% cited print and electronic media as their main sources of information on such subjects. Although the youngest reported age at first coitus was 8 years, the mean age for first intercourse among males and females were, respectively, 15.1 and 16.0 years. 22.6% and 8.3% respectively, of males and females had experienced sexual intercourse by age 14. 93.3% had been sexually active during the preceding 12 months, with 42.4% of these youths reporting having had sex with two or more partners during the period. 37.3% had had sexual intercourse with strangers, bar attendants, and prostitutes, although males were more likely to be involved with such individuals. 75.9% had not used any form of contraception. Communication and education on the risks of unprotected sexual activity are urgently needed in this sexually active population of youths which thus far remains largely ignorant about StDs and contraception.
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PMID:Knowledge of sexually transmitted diseases, HIV infection and AIDS among sexually active adolescents in Nairobi, Kenya and its relationship to their sexual behaviour and contraception. 792 41

The development of multi-drug resistance by enteric bacteria is an increasing problem in the developing countries. There is need to monitor antimicrobial susceptibility of these organisms in order to ensure appropriate treatment and control of infections. Antimicrobial susceptibility patterns, plasmid DNA content and restriction enzyme digests of plasmid deoxyribonucleic acid (DNA) were used to study 175 Salmonella and Shigella species isolated from predominantly HIV-seropositive adult patients in Nairobi, Kenya. All the isolates were sensitive to ciprofloxacin. A significantly higher proportion of Shigella species were resistant to chloramphenicol, cotrimoxazole, streptomycin and tetracycline compared to Salmonella species (p-value < 0.001). Multi-resistant Salmonella typhimurium isolates had 60, 40 and 5 MDa plasmids, the 5 MDa plasmid was absent in gentamicin sensitive isolates. In addition to 2-10 MDa range of plasmids, multi-resistant Shigella species had a heavy 100-105 MDa plasmid. Restriction enzyme digests were similar for the 60 and 40 MDa plasmid DNA bands from Salmonella typhimurium isolates but did not show any consistency among Shigella spp. Plasmid-encoded multi-drug resistance plays a major role in the spread of resistance among enteric bacteria. It is vital to use drugs rationally in order to control the emergence and spread of multi-drug resistance.
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PMID:Antimicrobial susceptibility and presence of extrachromosomal deoxyribonucleic acid in Salmonella and Shigella isolates from patients with AIDS. 792 59

Breast-feeding plays a potentially significant role in mother to child transmission of human immunodeficiency virus type 1 (HIV-1). The additional transmission risk attributable to breast-feeding and the factors that enhance or inhibit transmission are presently unknown. One mechanism by which breast milk might inhibit HIV-1 transmission is the presence of specific antibodies directed against HIV-1 in breast milk of seropositive mothers. In this study serum and breast milk samples from women in Nairobi, Kenya, were tested to determine the prevalence of HIV-1 IgA antibodies. A Western blot test developed in our laboratory was used to detect anti-HIV-1 immunoglobulin A in serum and anti-HIV-1 secretory IgA (sIgA) in breast milk. Ninety-four percent of 63 HIV-1 seropositive women had anti-HIV-1 IgA in serum and 59% had anti-HIV-1 sIgA in their breast milk. No significant associations with maternal characteristics or serum anti-HIV-1 IgA or IgG banding patterns and the presence of anti-HIV-1 sIgA in breast milk were found. No protective effect of anti-HIV-1 sIgA was seen regarding mother to child transmission; however, further studies are necessary to determine the effect of these antibodies in maternal sera or in breast milk on the efficacy of HIV-1 transmission.
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PMID:Human immunodeficiency virus type 1 IgA antibody in breast milk and serum. 797 Sep 47

Genital ulcers are implicated as a risk factor enhancing susceptibility to human immunodeficiency virus type 1 (HIV-1) infection. A prospective study to determine the incidence of and risk factors associated with acquisition of HIV-1 in women with genital ulcers was done. HIV-1-seronegative women with genital ulcers attending a clinic for sexually transmitted diseases in Nairobi were followed to HIV-1 seroconversion over a 6-month period. Of 81 women, 10 seroconverted to HIV-1. The crude 6-month incidence of HIV-1 infection was 12%. Risk factors associated with seroconversion included cervical ectopy (rate ratio [RR], 4.9; 95% confidence interval [CI], 1.5-15.6) and pelvic inflammatory disease (RR, 6.3; 95% CI, 1.9-20.4). Thus, cervical ectopy and pelvic inflammatory disease may increase susceptibility to HIV-1 in women with genital ulcers.
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PMID:Human immunodeficiency virus type 1 seroconversion in women with genital ulcers. 765 94


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