The idea is to create a low-cost, simple, rapid in-field diagnostic tool for the detection of the Rift Valley Fever virus. We know what you are probably thinking: what on earth is Rift Valley Fever and why did we choose this particular virus? We’ll begin by answering the first question.
Rift Valley Fever is a viral disease commonly observed in domesticated animals (such as sheep, goats, cattle & buffalo), however it also has the ability to infect and cause illness in humans. The disease was first detected in livestock in Kenya’s Great Rift Valley (hence the name) in the early 20th century. Since then, RVF has spread to regions of eastern, southern and sub-Saharan Africa with the first known outbreak of RVF outside of Africa being in Saudi Arabia and Yemen in 2001.
Why Rift Valley Fever?
Let us first start by considering the history of viruses within Africa. During the last two decades, more than 20 epidemics have spread through Africa, composing approximately 40% of all epidemics during this period. This high frequency arises from the fact that’s a considerable proportion of Africa lies below poverty limit. For many diseases currently posing threats to these areas, rapid test have been developed (e.g. Malaria detection tests are well-developed and readily available). However, there are still diseases for which lack such tests, such as Rift Valley Fever. Therefore, when its outbreaks take place, most recently in Kenya (2006), huge economic losses arise and lives are lost.
Outbreaks of RVF can be fatal to livestock and almost certainly results in abortions of and deaths to livestock (for more information please refer to http://www.who.int/mediacentre/factsheets/fs207/en/).
In the past there have been documented cases of Rift Valley Fever causing deaths in humans (594 deaths in Egypt in 1977-78, 400 deaths in Kenya in 1998) 1. Besides the viruses direct impact on humans (i.e. death), Rift Valley Fever also has severe indirect effects. It should be noted that livestock production and trade are vital sources of livelihood and income for rural African regions and when RVF proves fatal to livestock, the loss of livestock not only results in loss of income but also loss of food, which in turn can contribute to malnutrition resulting in additional health problems.
This is where we come in. We believe that earlier, quicker detection of RVF will allow the disease to be contained and result in fewer losses of livestock and income!
The current method of detecting RVF is by the antigen detection enzyme-linked immunosorbent assay (ELISA), which is an immunocapture test. The ELISA test is a quantitative analysis of Rift Valley Fever concentration. These current methods of detection are accurate, however they are not rapid (some tests take up to 3 days), not always practical for in-field use (some test require lab analysis) and not always affordable (approx. £12 for 1 animal2).
Using new technology that allows antibodies to conjugate to nano-particles, we hope to develop a cheaper, rapid, in-field diagnostic tool for detection of Rift Valley Fever within livestock.
To achieve this, we have set ourselves two goals: the first to prove that gold nanoparticles conjugated to the RVF antibodies change colour in presence of RVF antigens. Secondly, we are hoping to prepare an effective containing medium for the prepared conjugate.
1 Arzt J, White WR, Thomsen BV, Brown CC. “Agricultural diseases on the move early in the third millennium”. January 2010. Vet Pathol 47 (1); 15-27.