According to the World Health Organization, around 5.4 million people are bitten by snakes each year. Of those, about 400,000 are left with permanent injuries or disfigurements. Tragically, snakebites also cause between 80,000 and 140,000 deaths annually.
India experiences more snakebite deaths than any other country. As mentioned in the video above, an estimated 50,000 people die from snakebites in India each year, though local officials believe many cases go unreported. Even with possible underreporting, India still accounts for more than half of all snakebite-related deaths worldwide. One of the most dangerous snakes in the region is the saw-scaled viper, which is believed to be responsible for more human deaths than any other species.
The Saw-Scaled Viper
The saw-scaled viper, Echis carinatus, is endemic to the Middle East and the Indian subcontinent. It’s a comparatively small snake, with a short, stout body measuring 1–3 feet and weighing less than one pound. Their body colors are shades of brown, gray, reddish-orange, or olive, with irregular light spots edged in dark brown.
Saw-scaled vipers live in rocky, sandy desert and semi-desert regions. Their coloring allows them to camouflage themselves in burrows, crevices, leaves, or among loose rocks. They may even bury themselves in the sand. These snakes are nocturnal, hunting for prey such as small rodents and lizards when the sun has gone down. They are more active after rain and are most often seen during monsoon season.
Saw-scaled vipers are aggressive and quick to strike.
©Dushan Muthunayake/Shutterstock.com
How Did the Saw-Scaled Viper Get Its Name?
The saw-scaled viper takes its name from its unique saw-like scales. Their scales are keeled, which means they are not flat and smooth but have a rough ridge running down the middle of each scale. The scales on the sides of their bodies are not only keeled but also serrated — just like the teeth of a saw.
The snakes compress their bodies into an “S” shape when threatened. Then, they undulate to rub their serrated scales together. As you heard in the video, these movements make a dry, raspy sound as a warning. This process is called stridulation. The sound gets louder and faster as the snake becomes more agitated.
The World’s Deadliest Snake
There are several reasons why experts believe the saw-scaled viper has killed more humans than any other snake. Not only is the venom dangerous, but it is an extremely aggressive snake that rapidly strikes with the slightest provocation. There have even been reports of people being charged and chased by saw-scaled vipers, but they are not well-documented.
The venom yield from a mature snake is typically around 12mg, but 5mg is enough to kill an adult human. The dry bite rate is around 8%, which suggests the snake injects its victims with venom as often as 92% of the time. The venom is hemotoxic and cytotoxic, causing acute bleeding and tissue damage. Without treatment, the mortality rate is as high as 20%.
Scientists have developed a multi-species anti-venom that has been effective in 80% of patients with saw-scaled viper bites. Unfortunately, the timely availability of the anti-venom, lack of trained personnel to administer it, and reduced access to medical facilities increases the likelihood of serious injury or death.
