University of Zimbabwe

About: University of Zimbabwe is a education organization based out in Harare, Harare, Zimbabwe. It is known for research contribution in the topics: Population & Acquired immunodeficiency syndrome (AIDS). The organization has 4378 authors who have published 6800 publications receiving 160720 citations. The organization is also known as: UZ & University College of Rhodesia and Nyasaland.

High Rates of Clustering of Strains Causing Tuberculosis in Harare, Zimbabwe: a Molecular Epidemiological Study

Abstract: We examined the pattern of tuberculosis (TB) transmission (i.e., reactivation versus recent transmission) and the impact of human immunodeficiency virus (HIV) infection in Harare, Zimbabwe. Consecutive adult smear-positive pulmonary TB patients presenting to an urban hospital in Harare were enrolled. A detailed epidemiological questionnaire was completed, and tests for HIV type 1 and CD4 cell counts were performed for each patient. Molecular fingerprinting of the genomic DNA recovered from cultures of sputum was performed by two molecular typing methods: spacer oligonucleotide typing (spoligotyping) and analysis of variable number of tandem DNA repeats (VNTRs). A cluster was defined as isolates from two or more patients that shared the same spoligotype pattern or the same VNTR pattern, or both. DNA suitable for typing was recovered from 224 patients. The prevalence of HIV infection was 79%. Of 187 patient isolates (78.6%) typed by both spoligotyping and analysis of VNTRs, 147 were identified as part of a cluster by both methods. By spoligotyping alone, 84.1% of patient isolates were grouped into 20 clusters. The cluster size was generally <8 patient isolates, although three large clusters comprised 68, 25, and 23 patient isolates. A total of 89.4% of the patient isolates grouped into 12 clusters defined by analysis of VNTRs, with 2 large clusters consisting of 127 and 13 patient isolates, respectively. Thirty-six percent of patient isolates with a shared spoligotype and 17% with a shared VNTR pattern were geographically linked within Harare, but they were not linked on the basis of the patient's home district. In a multivariate analysis, there were no independent predictors of clustering, including HIV infection status. Comparison with the International Spoligotype database (Pasteur Institute, Pointe a Pitre, Guadeloupe) demonstrated that our three largest spoligotype clusters are well recognized and ubiquitous in Africa. In this epidemiologically well characterized urban population with a high prevalence of HIV infection, we identified a very high level of strain clustering, indicating substantial ongoing recent TB transmission. Geographic linkage could be detected in a proportion of these clusters. A small group of actively circulating strains accounted for most of the cases of TB transmission.

Bacterial vaginosis and the risk of trichomonas vaginalis acquisition among HIV-1-negative women.

Abstract: Background The vaginal microbiota may play a role in mediating susceptibility to sexually transmitted infections, including Trichomonas vaginalis (TV). This analysis evaluated the association between bacterial vaginosis (BV) and incident TV among women enrolled in a biomedical HIV prevention trial. Methods Data were analysed from HIV-1 seronegative women participating in HIV Prevention Trials Network Protocol 035. At quarterly visits for up to 30 months, participants completed structured interviews and specimens were collected for genital tract infection testing. TV was detected by saline microscopy. BV was characterised by Gram stain using the Nugent score (BV = 7–10; intermediate = 4–6; normal = 0–3 [reference group]). Cox proportional hazards models stratified by study site were used to assess the association between BV at the prior quarterly visit and TV acquisition. Participants were censored at their first TV infection or if they became pregnant or HIV-infected. Results This secondary analysis included 2,804 participants from Malawi, South Africa, USA, Zambia and Zimbabwe who contributed 13,977 follow-up visits. BV was detected at 5,184 (37.1%) visits and TV was detected at 352 (2.5%) visits. After adjusting for age, marital status, hormonal contraceptive use, sexual activity and TV at baseline, intermediate microbiota and BV at the prior visit were independently associated with an increased risk of TV (intermediate microbiota: adjusted hazard ratio [aHR] = 1.74, 95% confidence interval [CI] 1.22, 2.47; BV: aHR = 3.25, 95% CI 2.53–4.17). TV at baseline was also associated with an increased risk of TV (aHR = 2.54; 95% CI 1.91, 3.36). Sensitivity analyses excluding 202 women with baseline TV showed similar results (BV: aHR = 3.18; 95% CI 2.42 – 2.19). Conclusions Women with a Nugent score > 3 were at an increased risk of acquiring TV. If this relationship is causal, interventions that decrease the incidence of BV and promote a normal vaginal microbiota could potentially contribute to reductions in TV incidence.

Pb/Pb, SmNd and RbSr geochronology in the Archean Craton of Zimbabwe

Abstract: Pb isotope data for greenstone belt volcanic units, plutons and gneisses of the Archean Craton of Zimbabwe are presented together with SmNd isotopic analyses and model Nd mantle derivation (tDM) ages for selected samples. Pb/Pb whole-rock isochrons yield well-determined dates for the Cardiff Hill rhyolite of the Shamva-Harare greenstone belt (2659−39+38 Ma), the Somabula tonalite (2752−52+50 Ma), the Gwenoro Dam migmatitic gneisses (2705∂3+60 Ma), and for various suites from the Chingezi tonalite (from 2874±32 to 2686−94+88 Ma). Comparison of geochronological results from this study with those of earlier work (mainly RbSr whole-rock dating) shows some significant discordances, and their possible causes are discussed with regard to time-integrated Th/U ratios and the geological settings of the relevant rock units. The Chingezi and Sesombi plutons show good agreement between RbSr and Pb/Pb whole-rock isochron dates and also display a limited range of Th/U ratios, appropriate to a purely igneous differentiation history. Early to mid-Archean gneisses show large ranges of Th/U ratios, probably the results of U disturbances during metamorphism. In these rocks Pb/Pb dates may be older or younger than the corresponding RbSr dates, but tDM model ages generally agree with the older of the isochron results. The behaviour of the RbSr and UPb whole-rock systems during metamorphism may depend critically on the nature of the fluid phase evolved. CO2-rich fluids appear to be implicated in U enrichment of early Archean gneisses at the Shabanie Mine. It is argued that CO2-rich fluids may cause disturbance of the UPb system without resetting the RbSr system, while a H2O-rich fluid phase could have the reverse effect.

Factors Predicting Zimbabwean Students' Intentions To Use Condoms

Abstract: It is important to develop and apply AIDS prevention models. The capacity of the theories of Reasoned Action and Planned Behaviour to predict intended condom use was tested, using self-administered questionnaires. among 179 male and 123 female Zimbabwean teacher-trainees. Over 93% of males and 72% of females were sexually experienced. Scale reliabilities, which ranged from 0.46-0.90, were reasonable. Data were analyzed using multiple regression with hierarchical entry, first of the Theory of Reasoned Action dimensions, then the additional Theory of Planned Behaviour components. The additional elements of the Theory of Planned Action contributed little to the Theory of Reasoned Action, whose predictive capacity was itself largely accounted for by attitude towards behaviour. Concerns about the measurement of subjective norm are considered. With this proviso, results support the use of skills-based, cognitive-behavioural modification techniques to alter underlying beliefs and expectations respecting...