Tens of thousands of people die from snake bites worldwide every year. Lack of treatment and even the wrong medicine mean many of these deaths are preventable.
Snake bites may not strike you as being a major public health problem.
But in some parts of the world they are a daily risk, and can be lethal or life-changing.
Victims often do not get the treatment they need in time, if at all.
In other cases, they are given medicine to treat an injury caused by a different snake.
About 11,000 people a month are thought to die from venomous snakebites – similar to the number that died during the whole of the 2014-16 West Africa Ebola crises.
A further 450,000 people a year are thought to suffer life-changing injuries such as amputation and permanent disability.
The scale of the problem means snake bites are now classed as a priority neglected tropical disease.
In developed regions – such as Europe, Australia and North America – snake bites kill only a handful of people each year, despite there being many venomous species.
That is compared with 32,000 deaths in sub-Saharan Africa, and twice as many in South Asia.
Many rural communities in the tropics are at almost constant risk of snake bites, whether working in the field, travelling at dusk or even sleeping in their homes at night.
Young male farmers are the most at-risk group, followed by children.
While a large rural population is a factor, health systems in some parts of Africa and Asia are often ill-prepared for coping with snake bites.
Clinical training, emergency transport and affordable medicine are often in short supply, with tragic consequences.
Venomous snake bites typically cause three main types of life-threatening symptoms: uncontrollable bleeding, paralysis and irreversible tissue destruction.
It is essential for snakebite victims to get the correct medicine as soon as possible following a snake bite.
Antivenom is the medicine of choice for treating snake bites.
This means that many different versions are needed, because there are so many venomous snakes found throughout the world – cobras, mambas, kraits, vipers and pit vipers, to name just a few.
The toxins found in their venom differ from one group of snakes to the next, or even between the same group of snakes in a different region.
This means the correct antivenom is often hard to identify and can be very expensive.