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1.
Preprint in English | medRxiv | ID: ppmedrxiv-22281489

ABSTRACT

BackgroundThe impact of COVID-19 in Africa remains poorly defined. We sought to describe trends in hospitalisation due to all medical causes, pneumonia-specific admissions, and inpatient mortality in Kenya before and during the first five waves of the COVID-19 pandemic in Kenya. MethodsWe conducted a hospital-based, multi-site, longitudinal observational study of patients admitted to 13 public referral facilities in Kenya from January 2018 to December 2021. The pre-COVID population included patients admitted before 1 March 2020. We fitted time series models to compare observed and predicted trends for each outcome. To estimate the impact of the COVID-19 pandemic, we calculated incidence rate ratios (IRR) and corresponding 95% confidence intervals (CI) from negative binomial mixed-effects models. ResultsOut of 302,703 patients hospitalised across the 13 surveillance sites (range 11547 to 57011), 117642 (39%) were admitted to adult wards. Compared with the pre-COVID period, hospitalisations declined markedly among adult (IRR 0.68, 95% CI 0.63 to 0.73) and paediatric (IRR 0.67, 95% CI 0.62 to 0.73) patients. Adjusted in-hospital mortality also declined among both adult (IRR 0.83, 95% CI 0.77 to 0.89) and paediatric (IRR 0.85, 95% CI 0.77 to 0.94) admissions. Pneumonia-specific admissions among adults increased during the pandemic (IRR 1.75, 95% CI 1.18 to 2.59). Paediatric pneumonia cases were lower than pre-pandemic levels in the first year of the pandemic and elevated in late 2021 (IRR 0.78, 95% CI 0.51 to 1.20). ConclusionsContrary to initial predictions, the COVID-19 pandemic was associated with lower hospitalisation rates and in-hospital mortality, despite increased pneumonia admissions among adults. These trends were sustained after the withdrawal of containment measures that disrupted essential health services, suggesting a role for additional factors that warrant further investigation.

2.
PhytoKeys ; 191: 1-158, 2022.
Article in English | MEDLINE | ID: mdl-35437383

ABSTRACT

Taita Hills forests are an ecological island within the Tsavo plains and are the northern-most part of the Eastern Arc Mountains in southeast Kenya. They are highly fragmented forests embedded in a mosaic of human settlements and farms on the slopes and hilltops. Despite their intensive degradation, they exhibit a high degree of plant diversity and endemism, and therefore are regarded as a biodiversity hotspot. In spite of their distinct importance to the biodiversity of the region as well as supporting the livelihoods of the surrounding communities, floristic studies in these hills have been finite. Through repetitive floral expeditions, herbarium records from the East African Herbarium (EA), Global Biodiversity Information (GBIF), and the Integrated Digitized Biocollections (iDigbio) databases, as well as plant lists from literature and monographs, we provide a comprehensive checklist of 1594 taxa representing 159 families, 709 genera, 1530 species, 39 subspecies, 27 varieties, and 2 hybrids. Out of these, 75 are endemic or near-endemic, 59 are exotic, and 83 are listed as either endangered or near endangered as evaluated in the IUCN Redlist. Zehneriatuberifera G.W.Hu & Q.F.Wang, a new species to science, which has previously been described, was also discovered from the Ngangao forest fragment. Information on the habit(s), habitat(s), and altitudinal range of each taxon is provided in this study. This checklist is an updated inventory of the vascular plants of the Taita Hills. It confirms the high plant diversity of the hills and provides a clear baseline for strategic conservation and sustainable management of plant resources and diversity under the Convention on Biological Diversity (CBD).

3.
PhytoKeys ; 165: 85-98, 2020.
Article in English | MEDLINE | ID: mdl-33192148

ABSTRACT

Zehneria grandibracteata, a new species of Cucurbitaceae from western Kenya, is described here, based on morphological and molecular data. It has long been misidentified as the widely-distributed species Z. scabra. However, it differs by its ovate leafy probract at the base of the inflorescences, subglabrous condition of the entire plant, shorter receptacle-tube and filaments, as well as denser and sessile inflorescences. Furthermore, the molecular phylogenetic analysis of Zehneria, based on nrITS sequences, further supports the argument that Z. grandibracteata should be segregated from Z. scabra.

4.
PhytoKeys ; 155: 87-139, 2020.
Article in English | MEDLINE | ID: mdl-32863724

ABSTRACT

We compiled a checklist of the flora of South and North Nandi forests based on literature, online databases, herbarium collections and floristic field surveys. A combination of general walk-over surveys and plotless landscape sampling for plant collection and sight observation was used. We recorded 628 plant species representing 118 families and 392 genera, which almost double the latest results of the previous most recent survey. We found 61 species of ferns and fern allies and 567 species of seed plants, representing 9.98% of the total plant species in Kenya. Herbs were the majority (50.2%) of life forms followed by shrubs (16.5%). We report unique populations of three species out of 19 species that are widespread in Africa, but restricted to Nandi and Kakamega Forests in Kenya. Four of the recorded species are threatened globally and 16 exotic plant species were found. The recent description of one new species and two new records for Kenya from these forests, together with the comprehensive checklist is of crucial importance to the conservation of these unique ecosystems. Our results are essential to forest managers, community forest associations, conservationists, students and research scientists in Kenya and globally for implementing critical decisions for the conservation of this vital biodiversity resource.

5.
PhytoKeys ; 149: 1-88, 2020.
Article in English | MEDLINE | ID: mdl-32549745

ABSTRACT

The Aberdare Ranges Forest, located in the Central highlands of Kenya, is an isolated volcanic mountain in the East African Rift Valley with unique flora. Despite its refugial importance to rare and endemic plant species, the diversity of plants in the Aberdare Ranges Forest remains poorly understood. The checklist presented here is a collation of data obtained from multiple floristic surveys and from herbarium specimen collections from the forest. A total of 1260 vascular plants taxa representing 136 families, 613 genera, 67 subspecies and 63 varieties are documented. The ferns comprised 84 species, lycophytes seven, gymnosperms six and angiosperms were 1163 taxa. This represents 17.9% of the Kenyan taxa, 1.7% of the African taxa and 0.3% of all the vascular plants known in the world. A total of 18 taxa were endemic and 14 taxa were found to be threatened globally. The life form, voucher specimen(s), habitat and distribution range of each taxon and a brief analysis of taxa diversity is presented in this checklist. This is the first comprehensive inventory of vascular plants in the entire Aberdare Ranges, providing a solid basis for more sustainable management and improved conservation of this montane forest. The checklist is also an important contribution to the world checklist of plants required by the Global Strategy for Plant Conservation.

6.
PhytoKeys ; 131: 91-113, 2019.
Article in English | MEDLINE | ID: mdl-31582887

ABSTRACT

Distribution patterns of biodiversity and the factors influencing them are important in conservation and management strategies of natural resources. With impending threats from increased human population and global climatic changes, there is an urgent need for a comprehensive understanding of these patterns, more so in species-rich tropical montane ecosystems where little is known about plant diversity and distribution. Vascular species richness along elevation and climatic gradients of Aberdare ranges forest were explored. A total of 1337 species in 137 families, 606 genera, 82 subspecies and 80 varieties were recorded. Correlations, simple linear regression and Partial least square regression analysis were used to assess richness and diversity patterns of total plants, herbs, shrubs, climbers, arboreal and endemic species from 2000-4000 m above sea level. Total plant species richness showed a monotonic declining relationship with elevation with richness maxima at 2000-2100 m a.s.l., while endemic species richness had a positive unimodal increase along elevation with peaks at 3600-3700 m a.s.l. Herbs, shrubs, climbers and arboreal had significant negative relationships with altitude, excluding endemism which showed positive relations. In contrast, both air and soil temperatures had positive relationships with taxa richness groups and negative relations with endemic species. Elevation was found to have higher relative influence on plant richness and distribution in Aberdare ranges forest. For effective conservation and management of biodiversity in Aberdare, localized dynamic conservation interventions are recommended in contrast to broad and static strategies. Establishment of conservation zones and migration corridors are necessary to safeguard biodiversity in line with envisaged global climatic vicissitudes.

7.
Nature ; 476(7358): 51-6, 2011 Aug 03.
Article in English | MEDLINE | ID: mdl-21814275

ABSTRACT

The role of African savannahs in the evolution of early hominins has been debated for nearly a century. Resolution of this issue has been hindered by difficulty in quantifying the fraction of woody cover in the fossil record. Here we show that the fraction of woody cover in tropical ecosystems can be quantified using stable carbon isotopes in soils. Furthermore, we use fossil soils from hominin sites in the Awash and Omo-Turkana basins in eastern Africa to reconstruct the fraction of woody cover since the Late Miocene epoch (about 7 million years ago). (13)C/(12)C ratio data from 1,300 palaeosols at or adjacent to hominin sites dating to at least 6 million years ago show that woody cover was predominantly less than ∼40% at most sites. These data point to the prevalence of open environments at the majority of hominin fossil sites in eastern Africa over the past 6 million years.


Subject(s)
Biological Evolution , Ecosystem , Hominidae/physiology , Trees , Africa, Eastern , Animals , Calibration , Carbon Isotopes/analysis , Fossils , Gait/physiology , Hominidae/anatomy & histology , Paleontology , Plant Leaves/growth & development , Poaceae/growth & development , Population Dynamics , Soil/chemistry , Trees/growth & development , Tropical Climate , Wilderness , Wood
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