Publications by authors named "Joanna de Klerk"

Article Synopsis
  • Bluetongue virus (BT) affects various livestock species worldwide, causing economic losses and health issues, with most existing epidemiological models based on the BTV-8 outbreak from 2006-2009.
  • The study aims to create a flexible model for predicting BT outbreaks globally and to identify key factors influencing outbreak dynamics for better policy planning.
  • A two-host, two-vector model was developed and analyzed using updated parameters from literature, showing that factors like the infectious period of sheep and cows most significantly affect outbreak length and peak infection levels.
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Article Synopsis
  • Culicoides biting midges are key vectors for important veterinary viruses like bluetongue and African horse sickness, and their distribution is impacted by climate and environmental changes.
  • This study aimed to model the distribution of two primary Culicoides species using random forest machine learning, analyzing various climate and anthropological factors in South Africa where these diseases are common.
  • The random forest models successfully explained significant variance in Culicoides populations, with cattle density and water vapor pressure identified as the most critical predictors for the two species, outperforming traditional interpolation maps in predictive accuracy.
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African horse sickness is an equine orbivirus transmitted by Culicoides Latreille biting midges. In the last 80 years, it has caused several devastating outbreaks in the equine population in Europe, the Far and Middle East, North Africa, South-East Asia, and sub-Saharan Africa. The disease is endemic in South Africa; however, a unique control area has been set up in the Western Cape where increased surveillance and control measures have been put in place.

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Introduction: The consumption of dairy products contributes to health, nutrition, and livelihoods globally. However, dairy products do not come without microbiological food safety risks for consumers. Despite this risk, common hygiene measures in high-income countries, particularly pasteurisation, ensures that milk is safe, and is indeed frequently mandated by law.

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In the Cape Flats townships, Cape Town, South Africa, there are more than 250 working cart horses. They serve the community with scrap metal and garden refuse removal, human transport and the selling of goods. A questionnaire was undertaken to understand the social and economic impacts of a horse and cart in the Cape Flats on individual owners and/or drivers, their households and the community.

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