One of the educational components of the Livingstone Revisited 2024 expedition is to raise awareness of snake-bites and pilot a novel training program within Zambia. Aptly, we shall be delivering this in the town of Livingstone, and the project has been designed to have inbuilt monitoring and evaluation strategies to enable sustainable and reproducible longterm outcomes.
We anticipate that this will be able to be rolled out across the district and beyond, in conjunction with the Zambian Ministry of Health. It is obviously important to work with local experts and we have teamed up with Snake Safety Zambia and the herpetologist Marcel van Driel, who has drafted the National Guidelines in the Prevention and Management of Snakebite, which was validated and adopted by the Zambian Ministry of Health in October 2023 .
The size of the problem:
Globally, it is estimated that snakebite envenoming is responsible for more than 138,000 deaths and more than 400,000 permanent disabilities every year.
In sub-Saharan Africa, 314,000 snakebite envenomations cause between 5,900 to 14,600 amputations and 7,000 to 32,000 deaths each year. These figures are staggering, especially when you consider that up to 70% of snakebite cases remain unreported.
As a result of this, snakebite rightly re-joined the WHOs list of Neglected Tropical Diseases (NTDs) back in 2017.
The mainstay of developing any snake-bite strategy is to focus on prevention- changing behaviours and providing adequate lighting to prevent envenomation in the first place. This can be surprisingly hard to achieve, and some intersting work has been done by Harrison Carter in Tamil Nadu, India, investigating this, which you can read about here.
As well as causing droughts and impacting on power supplies, we also know that climate change is having a significant impact on ecology and the human-animal divide. Using geographic information systems (GIS) and state-of- the-art modelling techniques, the WHO are already predicting that deadly snake species will become more common and that they will come into contact with more people.
The majority (97%) of snakebite deaths occur in rural areas which depend on outdoor activities for livelihood, such as farming, fishing, hunting, and herding, and many of the clinics supported by the Virtual Doctors, one of our expedition partners, exist in rural areas.
We also know that snakebite incidents are highest among the most economically productive members of the community and that treatment can be difficult to access and also prohibitively expensive.
There are challenges for clinicians when it comes to being able to deliver care, and there are also many myths when it comes to the correct treatment strategies within Zambia, particularly with regards to the use of tourniquets and black stones. There is therefore a significant need for collaborative learning and this is part of the logic behind this strand of the expedition.
In addition, it is estimated that within Zambia, up to 30% of patients may initially consult with traditional healers and this can cause further delay in accessing appropriate treatment. This can be difficult to address without getting buy in from local healers and communities, and part of the project will be to explore these ideas and how local clinicians can discuss these with patients locally in a non-judgemental manner.
First Aid Management
Patients who have been bitten should be managed using a stepwise DRCABC approach. It is important to check that the snake is no longer a threat and to avoid further risk of envenomation. Sometimes, the victim may have sustained a dry bite, however it is always best to err on the side of caution and keep this as a diagnosis of exclusion.
First principles are to keep the casualty calm and immobile to avoid increasing their heart rate and reduce the spread of venom systemically. The subsequent treatment strategy depends largely on the clinical prodrome they develop as illustrated below in the SSZ poster, which we shall be using during our training:
Regardless of the pre-hospital management, all suspected bite patients should be taken to hospital for monitoring and further workup.
What about anti-venoms?
It is no secret that there have been, and still are, significant challenges with regards to obtaining and using anti-venom across Africa. The main barriers were described in the Lancet in 2015 by the African Society of Toxinology:
"better region-specific antivenom development and distribution needs accurate epidemiological studies; medical staff need training to optimise product selection and use; and purchasing support programmes should standardise charges on behalf of stakeholders (governments and private employers, especially agricultural firms, health insurance providers, etc) to mutualise the costs equitably."
The Fav-Afrique antivenom was previously used extensively within Africa. It was taken off the market in 2010 by Sanofi, a move that lead to significant outcry by MSF at the time.
Fastforward to present day, and Micropharm a pharmaceutical company based in West Wales, are in the process of re-developing Fav-Afrique, with support from the Wellcome Trust.
Of course, there are also other anti-venoms being used within Zambia and other countries within Africa, however at present, none of these are made on the African continent, with many being made overseas in India or elsewhere in Asia.
This can lead to issues with supply, cost and logistics, and it is also important to appreciate that not all anti-venoms can treat all snake bites. At present, there is no such thing as a universal anti-venom- a pancea for all envenomations. Instead, monovalent anti-venoms are used to treat one particular snake or species, whereas polyvalent anti-venoms can potentially treat several different species.
It is therefore advantageous to know what you are treating, as this may influence the type of anti-venom you require, however bystanders should not make efforts to kill or recover the snake.
There are clear indications for anti-venom which are beyond the scope of this blog, however. usually anti-venoms are not given in a pre-hospital setting due to the risk of anaphylaxis, unless there is access to adrenaline, and full resuscitation kit.
If you want to find out more about what we are doing on the Livingstone Revisited 2024 Expedition, please visit our website: www.livingstonerevisited.com
If you would like to donate to support the expedition and help improve sustainbale healthcare outcomes in Zambia, you can donate to our Just Giving Page
Thank you for your generosity.
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