Adventurous Sam Owen is lucky to be alive after contracting a disease from rat urine while kayaking down a river.
Brave Sam, 24, believes the bacteria entered his body through his eyes and nose, as well as grazes on his hands from rock climbing.
He was rushed to hospital after he began vomiting and had excruciating back ache before being diagnosed with Weil's disease, which attacks the organs and can be fatal.
Sam, of Petersfield, Hants, said: "I read there was two weeks from when your contract it to going pass the point of surviving, I was 17 days so I shouldn't have survived. I am extremely lucky and grateful to be alive.
"I was doing an outdoor instructor course and spent the weekend in Wales doing some rock climbing. I came back and was doing some kayaking in the Itchen River, in Southampton, it was the first time I have ever kayaked. I was learning to capsize with a girl who didn't quite have the strength to turn me over so I was capsizing a lot more than others in my group.
"I found out Weil's disease could get in through your eyes, nose and through the scrapes on my hands from climbing - I think that was the cause."
After returning to his job a few days later as a full-time lifeguard he came home from a shift and started throwing up blood.
His worried mum dialled 111 who suggested he see a doctor the following day, which then sent him straight to hospital.
Sam added: "While I was in hospital a couple of my friends visited and they said to me you look really, really green. While I was on the ward I ate a slice of ham with cheese sauce on it and I began throwing up black sick, it wasn't very nice.
"I was taken into the ITU and had a central line put in my neck, my heart rate was 140 beats per minute just lying down, which is very high.
"I was there for five days before a consultant said me I need to know everything you were doing up to the point you began feeling ill. As soon as I told him about the kayaking they gave me an antidote to try and fight the disease. It attacks the kidney, liver, before making its way through your organs."
There were 70 hospital admissions for Weil's disease last year - more than any other 12-month period in the past ten years and double the figure for two years ago, according to NHS records.
The illness - also known as leptospirosis - has claimed four lives in the UK since 2009.
Olympic rowing champion Andy Holmes died of Weil's disease in 2010 aged 51, after it is believed the bacteria entered his body through blisters on his hands.
Doctor John Knighton "It is fairly rare. It is a bacteria that is transmitted through the urine of rats; infected rates urinate into an environment that allows the bacteria into humans.
"That either occurs from swallowing or enters the body through a break in the skin be that cuts or grazes. Drain workers, farm workers and vets who have occupational exposure are most vulnerable. We think Sam got it because he had been canoeing in the river three weeks before. Sam has recovered very well but it can be fatal."