Could Emirati camels hold the key to treating venomous snake bites?
Top vets believe the antivenom would be much more effective than the antibodies currently extracted from horses and goats
There can be few more terrifying experiences than being bitten by a poisonous snake.
As the fangs go in, they inject venom, a highly modified form of saliva packed full of poisons that can, with the most dangerous snakes, prove fatal.
Indeed, of the approximately five million people who are bitten by snakes each year, up to about 125,000 die, according to figures quoted by the London-based Royal Society of Tropical Medicine and Health.
Surprising though it may sound, camels could help to save people bitten by snakes, as Dubai's Central Veterinary Research Laboratory (CVRL) has researched using them to produce antivenom against snakebites.
A lack of funding has meant that the research has been on hold for several years, but Dr Ulrich Wernery, the CVRL's scientific director, hopes to secure finance to take the project forward.
“I'm very clear that this would be the best snake antivenom in the world, much better than when produced with horses or other small ruminants like goats,” said Dr Wernery.
Snake bites are thought to be rare in the UAE and Oman but sightings are not uncommon.
In November, a Ras Al Khaimah resident found one of the world's deadliest snakes outside his home, and last month an Emirati family had to have their car taken to pieces after a viper slithered into the vehicle during a camping trip in Masafi.
This would be the best snake antivenom in the world, much better than when produced with horses or other small ruminants like goats
Dr Ulrich Wernery
In studies carried out at the CVRL a few years ago, a small amount of venom was injected into the camel regularly over several weeks. In response to the presence of the toxins, the animals produced antibodies, proteins used to protect the body from pathogens and other harmful foreign bodies.
These antibodies could be purified and used, in serum form, in an antivenom.
Currently, horses or sheep are often used to produce antivenom, but using camels instead would offer several advantages, according to Dr Wernery.
Firstly, camel antibodies are a fraction of the size of those of other mammals, and are as a result known as nanobodies.
Being only a tenth the size of normal antibodies allows the nanobodies to more easily penetrate the tissue of the person who has been bitten to neutralise the toxins.
Another advantage, said Dr Wernery, is that antivenom produced by camels is less likely than that generated from horses to cause an allergic reaction when injected into a person. Sometimes, with horse antivenom, the reaction is “worse than the effect of the snake venom”.
The CVRL research, carried out in association with Professor Robert Harrison of the Liverpool School of Tropical Medicine in the United Kingdom, reached the stage of producing a rough version of antivenoms against several African snakes.
For the antivenom to be made widely available, this process would have to be perfected, and the antivenom tested and produced in large quantities. Dr Wernery said the antivenom could also undergo trials on people in hospitals in areas where snake bites are common.
The researchers would like to produce an antivenom that is effective against multiple types of snake bite, not just one. This offers great advantages.
“Much of the time people don't know which snake has bitten them,” said Dr Wernery.
One factor making it harder to secure funding for antivenom research is that the people who are bitten by snakes most often are from poorer communities, often being farm workers in developing countries. This means that drugs developed to benefit them are less likely to generate large amounts of revenue.
Despite the benefits conferred by their nanobodies, camels have not yet been widely used to produce antivenom of any kind, Dr Wernery said, although there has been some research in Morocco on using camels to generate scorpion antivenom.
“In South Africa, they do it with horses. In Riyadh they do it with horses,” he said, adding that using camels would be much easier.
“It has big, big advantages. Camels can be kept much more cheaply than horses and you can keep them outside even if it's very hot.”
Also, antivenom itself produced from camels is more resistant to high temperatures, a particular advantage given that many countries with poisonous snakes have a hot climate.
“With camel antivenom, this can be stored more closely to people who work as agricultural workers. It doesn't have to be [kept in a] hospital,” he said.
Dr Wernery said “absolutely” he is hoping that a pharmaceutical company will step in to help the research to progress.
Camel nanobodies are useful for producing much more than antivenom. As reported in The National, the CVRL has been involved in research involving using them to neutralise HIV, the virus that causes Aids.
Published: April 1, 2019 12:53 PM