Beau was helping his mum with the yard work. No one realised something was wrong until he collapsed.

Queensland teenager Beau Horan was in his family backyard on Monday afternoon when he started feeling unwell. But it was only when the 16-year-old went inside his home at Wurdong Heights, a rural suburb near Gladstone, and collapsed that his family realised something was wrong.

Frantic, they called an ambulance. It was then they discovered Beau had been bitten on the foot by a snake.

Paramedics rushed Beau to a nearby hospital in a life-threatening condition before he was flown by rescue helicopter to the Royal Brisbane and Women's Hospital, where he was put on life support.

He died in hospital on Thursday morning, per the ABC.

Beau's family said the teen didn't know he had been bitten. Then he suddenly collapsed and hit his head, causing a traumatic brain injury.

His mum, Bek Eddy told Mamamia Beau was a "fantastic kid who loved playing games with his mates".

"Loved a game of uno and was fiercely loyal to his sisters," she said.

Family friend Shaun Connolly said: "It is with overwhelming sadness that we share the loss of 16-year-old, Beau Horan, who after being bitten by a snake, has tragically passed away. Despite the urgent medical care he received and efforts to save him."

"Beau was a vibrant, compassionate, loving young man with so much to live for, with a bright future ahead of him. His passing has left an indescribable emptiness in our hearts and the family," he said.

Watch: Abbie Chatfield gets bitten by a snake on I'm a Celebrity Get Me Out of Here. Post continues below.

Authorities are yet to determine what type of snake bit the teenager. However, it's suspected to be an eastern brown snake — the only species in the world that kills people in under 15 minutes, according to Australian Geographic.

A fundraiser has been started to support Beau's family.

"As we try to process this devastating loss, we are reaching out to help Beau's mum, Bek Eddy, to cover the unexpected medical and funeral costs. Your generosity will provide Bek and Beau's family with some relief as the family navigate this overwhelming loss," Shaun wrote on the fundraiser.

"We are forever grateful for your love, prayers, and generosity. Thank you for honouring in memory of Beau's life with us."

How to avoid snake bites in Australia.

Following Beau's death, snake catcher Troy Hovenden, who runs The Reptile Bloke, shared a warning about eastern brown snakes.

"Something that people might be surprised to learn is that Eastern brown snake bites are painless and there have been cases when people have been bitten but thought it was just a scratch from a stick. Consequently, the person brushes it off and keeps walking along completely unaware of the situation," he said.

"Brown Snake venom can take effect very quickly so before long the bitten person begins to feel unwell and collapses. This seems to be what has happened in this particular incident."

The species is widespread throughout eastern Australia, from northern Queensland to South Australia, and is at its most active in spring, according to the Australian Museum.

Eastern brown snakes are an alert, nervous species and often react defensively if surprised or concerned. While they don't necessarily want to hurt humans, they'll strike with little hesitation if they feel threatened.

Troy's snake bite safety tips include:

• Always leave snakes alone. Do not attempt to catch, kill or interfere with a snake in any way.

• Wear enclosed shoes and trousers when in the outdoors.

• Wear gloves and a long sleeve shirt when gardening.

• When out in the garden, or in the bush, do not put your hands (or feet) where you can't see them.

• Always stick to clear paths so you can see where you are stepping.

Feature image: GoFundMe.