Browsing by Subject "Botswana"
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Item Open Access Comparative analyses of clinical and environmental populations of Cryptococcus neoformans in Botswana.(Mol Ecol, 2015-07) Chen, Yuan; Litvintseva, Anastasia P; Frazzitta, Aubrey E; Haverkamp, Miriam R; Wang, Liuyang; Fang, Charles; Muthoga, Charles; Mitchell, Thomas G; Perfect, John RCryptococcus neoformans var. grubii (Cng) is the most common cause of fungal meningitis, and its prevalence is highest in sub-Saharan Africa. Patients become infected by inhaling airborne spores or desiccated yeast cells from the environment, where the fungus thrives in avian droppings, trees and soil. To investigate the prevalence and population structure of Cng in southern Africa, we analysed isolates from 77 environmental samples and 64 patients. We detected significant genetic diversity among isolates and strong evidence of geographic structure at the local level. High proportions of isolates with the rare MATa allele were observed in both clinical and environmental isolates; however, the mating-type alleles were unevenly distributed among different subpopulations. Nearly equal proportions of the MATa and MATα mating types were observed among all clinical isolates and in one environmental subpopulation from the eastern part of Botswana. As previously reported, there was evidence of both clonality and recombination in different geographic areas. These results provide a foundation for subsequent genomewide association studies to identify genes and genotypes linked to pathogenicity in humans.Item Open Access Predictors of Poor Outcomes Among Infants with Respiratory Syncytial Virus-associated Acute Lower Respiratory Infection in Botswana(2020) Patel, Sweta MBackground: Acute lower respiratory infection (ALRI) is the leading infectious cause of death among children worldwide, and respiratory syncytial virus is the most common cause of ALRI. The majority of deaths occur in low- and middle-income countries, but there is a dearth of data on risk factors for poor outcomes in these settings. We endeavored to identify clinical and microbiome-related factors associated with poor outcomes among children hospitalized with RSV-ALRI in Gaborone, Botswana. Methods: Children 1-23 months of age presenting for care at Princess Marina Hospital who met the World Health Organization (WHO) definition of clinical pneumonia were enrolled in this prospective study and followed until hospital discharge or death. Nasopharyngeal swabs were collected for respiratory viral testing and microbiome analysis. Results: Young age (<6 months), household use of wood as a cooking fuel, moderate or severe malnutrition, and oxygen saturation <90% on room air were independent predictors of clinical nonresponse at 48 hours. Among HIV-uninfected infants 6 months of age or younger, HIV exposure was associated with a higher risk of in-hospital mortality. Nasopharyngeal microbiome composition and diversity were not associated with clinical nonresponse. Conclusions: We identified several risk factors for poor outcomes from RSV-ALRI among children in Botswana. These data could inform future use of RSV vaccines and therapeutics in these populations.
Item Open Access The 2020 elephant die-off in Botswana.(PeerJ, 2021-01-11) van Aarde, Rudi J; Pimm, Stuart L; Guldemond, Robert; Huang, Ryan; Maré, CelestéThe cause of deaths of 350 elephants in 2020 in a relatively small unprotected area of northern Botswana is unknown, and may never be known. Media speculations about it ignore ecological realities. Worse, they make conjectures that can be detrimental to wildlife and sometimes discredit conservation incentives. A broader understanding of the ecological and conservation issues speaks to elephant management across the Kavango-Zambezi Transfrontier Conservation Area that extends across Botswana, Namibia, Angola, Zambia, and Zimbabwe. Our communication addresses these. Malicious poisoning and poaching are unlikely to have played a role. Other species were unaffected, and elephant carcases had their tusks intact. Restriction of freshwater supplies that force elephants to use pans as a water source possibly polluted by blue-green algae blooms is a possible cause, but as yet not supported by evidence. No other species were involved. A contagious disease is the more probable one. Fences and a deep channel of water confine these elephants' dispersal. These factors explain the elephants' relatively high population growth rate despite a spell of increased poaching during 2014-2018. While the deaths represent only ~2% of the area's elephants, the additive effects of poaching and stress induced by people protecting their crops cause alarm. Confinement and relatively high densities probably explain why the die-off occurred only here. It suggests a re-alignment or removal of fences that restrict elephant movements and limits year-round access to freshwater.Item Open Access UNDERSTANDING HUMAN-LARGE CARNIVORE CONFLICT IN CHOBE, BOTSWANA(2008-04-28T20:55:31Z) Nijhawan, SahilLarge carnivores most often get in conflicts with people because they compete for resources that humans require-space and food. Throughout Africa, large carnivores have been eliminated or significantly reduced because of livestock predation. This study is part of the Large Carnivore Research Project initiated by African Wildlife Foundation (AWF) in the Chobe-Caprivi area of Botswana and Namibia respectively. Using GPS collars (a male and a female lion) and spoor counts, data are being gathered on population size, distribution, movement patterns and habitat use of large carnivores. Human impacts are also being examined through mapping of settlements and community interviews. Preliminary results confirm that areas of high carnivore activity correlate positively with protected areas and water availability, and negatively with human presence. Analysis of GPS data (Nov 2004-Oct 2005) from the collared lions has indicated a clear preference for grassland however, male prefers woodland and shrubby savannah more than the female. Additionally, enormous difference in space usage was observed between male and female lion, which is likely to bring males closer to humans and exacerbate conflicts. Male lion was closest to the human settlements in the dry season (April-September) during dawn and dusk. Results from this project will be incorporated into the current Chobe Land Use and Management Plan in order to effectively manage land and mitigate existing conflict between people and carnivores and ensure the survival of large carnivores in the region.