Ironman athletes are attacked by terrifying sea creatures during swim race off Hawaiian coast

The annual Ironman World Championship in Hawaii turned treacherous this weekend when triathletes were forced to navigate a bloom of jellyfish in the Pacific waters around the Big Island.

Competitors Menno Koolhaas of the Netherlands and Australian Matt Burton have both publicly shared their terrifying experiences after several rivals were stabbed on Saturday. Burton believes he had “an anaphylactic reaction” to a few stings before quitting the race to seek medical attention.

“I had quite a bit of pain while swimming and basically as soon as I dove in, probably within 10 or 20 strokes,” Burton said in a self-shot Instagram video. “I guess I was hoping it would subside a little bit. It’s like being stung by angels at home [but] I actually had a little more pain than I had previously experienced. And then I got on the bike and it actually just got worse.

‘The medical services here were great, just making sure I was okay – my blood pressure was sky high.’

Koolhaus, meanwhile, admitted he feared for his life after being stabbed: ‘My heart was beating like crazy and I thought I might die or something’

Menno Koolhaas from the Netherlands leaves the water on Saturday after being stung by jellyfish

Tobias Hallebach of Germany competes in the swimming portion of the 2024 VinFast IRONMAN World Championship on October 26, 2024 in Kailua Kona, Hawaii

Tobias Hallebach of Germany competes in the swimming portion of the 2024 VinFast IRONMAN World Championship on October 26, 2024 in Kailua Kona, Hawaii

Matt Burton has since revealed the jellyfish stings he suffered, such as the one on his shoulder

Matt Burton has since revealed the jellyfish stings he suffered, such as the one on his shoulder

Remarkably, Koolhaus recovered to finish fifth – the best ever result by a Dutchman in the event, according to Tri247.com.

“It started very badly: I was stung by a jellyfish and it was really painful,” Koolhaus told reporters afterwards.

“But Ironman is also a sport of being mentally strong and I had to be that and make the best of it,” he continued. ‘I think this was one of my best performances, but also mentally, which I am very proud of. I’m a rookie in Hawaii for the first time and I’m in the top five, that’s all I could dream of.”

Both Burton and Koolhaas seem to be doing better.

An aerial view as athletes compete in the swimming portion during the VinFast IRONMAN race

An aerial view as athletes compete in the swimming portion during the VinFast IRONMAN race

The moon jellyfish is one of many species found in the waters around Hawaii

The moon jellyfish is one of many species found in the waters around Hawaii

“I’m healthy now,” Burton said. ‘I’m doing well. You always hope that luck will be on your side, but sometimes you have no control over that at all.’

Jellyfish can inject venom through thousands of microscopic stingers. Some leave welts on central areas of the skin, as seen in Burton’s Instagram video, while others can cause serious health problems all over the body.

In some cases, jellyfish stings can be fatal.

German Patrick Lange was the winner in Hawaii on Saturday.