About This Project

Recently, tuberculosis was discovered in populations of African black and white rhinoceroses in Kruger National Park (KNP), South Africa. In order to prevent the spread of this deadly disease, movement restrictions have been imposed on rhinoceros in KNP. The aim of this project is to develop new diagnostic tests to determine infection and allow uninfected animals to be moved outside of this endemic area.

Ask the Scientists

What is the context of this research?

Currently, the largest populations of African rhinoceros exists in protected areas such as KNP. Despite protection, rhinoceros in these areas are still threatened by poaching and disease, such as TB (1,2,3,4). The discovery of TB in these species has lead to imposed movement restrictions from KNP, which hinders conservation efforts to save rhinos by spreading the population. Early discussions with decision-makers in South Africa led to an agreement to develop a plan so that rhinoceros can be tested for TB and those that pass the quarantine and testing program, can be moved. Unfortunately, large knowledge gaps exist how TB gets transmitted to and from rhinos, progression from infection to disease, ecological impact, etc (5). To fill these gaps, reliable diagnostic tools are needed.

What is the significance of this project?

TB results from chronic infection and can lead to fatal disease in people and animals. Animals can carry the bacteria for months and even years before becoming sick. TB can be transmitted between different species of animals (domestic and wildlife) and even between people and animals. Understanding the disease is the first step in preventing further spread to other animals, especially threatened and endangered species such as rhinoceros, lions, wild dogs and African elephants. The loss of apex predators to TB will have detrimental effects on the ecosystem in KNP. This highlights the impact this disease may have in disrupting conservation plans and efforts to maintain biodiversity. New approaches to detect the spread of the disease are urgently needed.

What are the goals of the project?

We will determine the efficacy of blood and sputum diagnostic tools for the diagnosis of TB infection from banked (n = 50) and newly obtained (n = ~50) rhinoceros samples.

This will be achieved by modifying an existing animal blood TB test and using a human TB DNA test. The blood test enable us to measure the animal's immune response, indicating if it has encountered TB before or not. To measure this memory, we will challenge the animal's blood with TB-specific antigens and measure the amount of native rhinoceros immunological messenger molecules secreted by its immune cells. This requires that we purchase specific reagents to capture these molecules for measurement. For the human TB DNA test, we need to purchase the available cartridges able to directly detect TB in respiratory samples.