A new study has revealed that certain deadly Indian snake species, including cobras and kraits, can still deliver venom even after death. Previously, this ability was thought to be limited to specific species like rattlesnakes and spitting cobras. However, researchers in Assam found that Indian monocled cobras and kraits can inject venom hours after their death, the Independent reported. The study was published in the journal Frontiers in Tropical Disease.
The research team, led by Susmita Thakur from Namrup College in Assam, documented three incidents involving venomous snakes. Two cases involved monocled cobras (Naja kaouthia) and one involved a black krait (Bungarus lividus), all reported to rural health centres in Assam.
First Incident
In the first instance, a 45-year-old man killed a snake that was attacking chickens in his home by beheading it. When the man tried to dispose of the snake's body, the severed head bit him on the thumb. He immediately felt severe pain radiating from the bite site to his shoulder. At the hospital, he reported symptoms including repeated vomiting, unbearable pain, and the bite area began to blacken. A photo of the snake helped doctors confirm it was a monocled cobra bite.
The man received intravenous antivenom and pain relief medication at the hospital and was discharged after 20 days with follow-up care for wound management.
"The pain significantly decreased following this treatment. The patient did not develop any symptoms of neurotoxicity," the researchers noted.
Second Incident
In a separate incident, a man working in a paddy field accidentally ran over a monocled cobra with his tractor. However, when he stepped off, the supposedly dead snake bit him on the foot. The patient experienced severe pain, swelling, and discolouration at the bite site, as well as two episodes of vomiting in the hospital, indicating envenomation. Although there were no signs of neurotoxicity, the bite caused an ulcer.
"Despite being crushed and presumed to be dead for several hours, the snake was capable of delivering a venomous bite, requiring antivenom treatment along with extended wound care," the researchers wrote.
Third Incident
In the third incident, a black snake entered a house and was killed, with its body discarded in the backyard. A neighbour who later picked up the snake's head was bitten on the finger. Within hours, the neighbour experienced difficulty swallowing and drooping eyelids.
Doctors identified the snake as a black krait (Bungarus lividus) and confirmed that the bite occurred despite the snake having been dead for 3 hours. The patient's condition worsened despite receiving 20 vials of polyvalent antivenom, and he became quadriplegic and unresponsive. After 43 hours of respiratory support, his condition improved, and he was discharged from the hospital in good health after six days.
Why does it happen?
Based on these incidents, researchers cautioned that snakes can still deliver venom even after fatal injuries, posing a risk of severe complications.
The researchers found that certain snakes' venom apparatus allows them to deliver venom even after death due to its unique structure. The venom gland, connected to a hollow fang, can still release venom if accidentally pressed while handling the severed head. This can lead to severe symptoms similar to those caused by live snake bites.
