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.

Evolution of the Major Pilus Gene Cluster of Haemophilus influenzae

Abstract: Haemophilus influenzae is a ubiquitous colonizer of the human respiratory tract and causes diseases ranging from otitis media to meningitis. Many H. influenzae isolates express pili (fimbriae), which mediate adherence to epithelial cells and facilitate colonization. The pilus gene (hif) cluster of H. influenzae type b maps between purE and pepN and resembles a pathogenicity island: it is present in invasive strains, absent from the nonpathogenic Rd strain, and flanked by direct repeats of sequence at the insertion site. To investigate the evolution and role in pathogenesis of the hif cluster, we compared the purE-pepN regions of various H. influenzae laboratory strains and clinical isolates. Unlike Rd, most strains had an insert at this site, which usually was the only chromosomal locus of hif DNA. The inserts are diverse in length and organization: among 20 strains, nine different arrangements were found. Several nontypeable isolates lack hif genes but have two conserved open reading frames (hicA and hicB) upstream of purE; their inferred products are small proteins with no data bank homologs. Other isolates have hif genes but lack hic DNA or have combinations of hif and hic genes. By comparing these arrangements, we have reconstructed a hypothetical ancestral genotype, the extended hif cluster. The hif region of INT1, an invasive nontypeable isolate, resembles the hypothetical ancestor. We propose that a progenitor strain acquired the extended cluster by horizontal transfer and that other variants arose as deletions. The structure of the hif cluster may correlate with colonization site or pathogenicity.

Soil fertility management effects on maize productivity and grain zinc content in smallholder farming systems of Zimbabwe

Abstract: Low soil zinc (Zn) threatens crop production and food nutrition in most cereal-based cropping systems in Africa. Agronomic management options that include farmers’ locally available organic nutrient resources need to be evaluated in the context of Zn nutrition in staple cereals. A three-year study (2008–11) was conducted in two smallholder farming areas of eastern Zimbabwe to evaluate the influence of farmers’ diverse soil fertility management practices on soil Zn status and effect on uptake patterns and nutritional value in maize (Zea mays L.). Participatory research approaches and formal surveys enabled identification of farmers’ diverse soil fertility management practices, which were then classified into five main domains: manure or woodland litter + mineral fertilizer; sole mineral fertilizer; legume – maize rotation; and a non-fertilized control. Over 60 randomly selected farms in each study area were then surveyed for influence of identified practices on soil Zn status across the domains. Maize growth, yield and Zn uptake patterns were monitored on a sub-sample of 20 farms covering the five management domains in each study area. Ethylenediaminetetraacetic acid (EDTA) extractable soil Zn ranged from 0.50 to 2.43 mg kg−1. Different farmer management practices significantly influenced Zn uptake (p 2.1 t ha−1 maize grain, against <0.8 t ha−1 in the non-fertilized control. Maize grain Zn concentrations increased by 46–64 % over the control. Regardless of management practice, resultant phytic acid to Zn (PA: Zn) ratios were above the critical value of 15 suggesting inadequacies in current farmer management options. We conclude that the current farmer soil fertility management regimes are insufficient to influence Zn nutrition in maize grown without external Zn fertilization on Zimbabwean sandy soils.

Lake Chivero: A management case study

Abstract: Lake Chivero in Zimbabwe was shown to be hypereutrophic. Historical data showed that the eutrophication process had been arrested in the late 1970s. However, a combination of poor planning, multiplicity of jurisdiction, mismatch between rate of urbanization and waste management investment, recent changes in the local climate and a permissive, immature political system that called for no public accountability resulted in environmental management breakdown leading to hypereutrophication of the lake. The case of Lake Chivero is presented as an example of a wider global issue regarding the status of environmental management in competition with other priorities in emerging democracies.

The feasibility of voluntary counselling and HIV testing for pregnant women using community volunteers in Zimbabwe.

Abstract: The purpose of this pilot project was to assess the feasibility and acceptability of voluntary counselling and HIV testing (VCT) by pregnant women using community volunteers in Zimbabwe to prevent mother to child transmission (MTCT) of HIV. From July 1999 to June 2001, a short-course zidovudine (ZDV)-based perinatal HIV prevention programme was initiated in two antenatal clinics. Community volunteers, recruited from local community organizations, underwent a two-week training course in VCT, which included HIV/AIDS facts, systematic counselling approach, and practical counselling techniques using scripts and role-play. Rapid HIV testing was performed after informed consent. Lay counsellors conducted individual pre- and post-test counselling for HIV. A total of 35 women community volunteers were trained in VCT; 34 graduated and committed to work four hours per week in the clinic. Of the 6051 pregnant women presenting for antenatal clinics (ANC), 1824 (30%) underwent pre-test counselling and 1547 (26%) were tested, and 429 (28%) were HIV infected. Overall, 1283 (83%) returned for their test results including 406 (95%) of HIV-infected women. Of the 406 HIV-infected women who collected their test results, only 203 (50%) opted for ZDV prophylaxis to prevent MTCT of HIV. Over the two-year study period, two counsellors died and three sought employment at other organizations. Adherence to duty roster was 97% and no breach of confidentiality was reported. Despite many challenges, VCT delivered by community volunteers is feasible and acceptable for pregnant women aiming to reduce their risk of transmitting HIV to their infants. This programme is being implemented at several urban and rural MTCT sites in Zimbabwe and can serve as a model for other resource-poor countries.

Water losses and the political constraints to demand management: the case of the City of Mutare, Zimbabwe

Abstract: The question posed in this paper is: why is the concept of water demand management rarely implemented on the ground? To answer this question the paper presents data on the water supply situation in the City of Mutare, Zimbabwe. It describes Mutare’s water infrastructure, the patterns of water use during the period 1980–2000; and our attempts to identify and quantify water losses in the system. Suggestions are made how these losses can be reduced, which would involve relatively modest resources. The question is then asked why these measures have not yet been taken. The paper contrasts this to the Pungwe scheme, a new water supply project of huge proportions which was conceived and implemented fairly quickly. The fact that water is a vital yet finite and fugitive resource explains why powerful water coalitions may emerge between engineers, financiers and politicians. It is the experience from Mutare and elsewhere that such coalitions tend to favour supply-side solutions to water scarcity. For effective adoption of water demand management it is essential to acknowledge this political dimension. As a strategy it is suggested that: (a) stakeholders should be better informed about alternative solutions to water problems; (b) a new generation of engineers trained in integrated water resources management is needed with the skills to carefully study the problem definition before rushing to solutions; and (c) financiers should be made aware of the relevance and economic rationale of demand management solutions.