Two dogs in Essex have died and three others needed blood transfusions.
American Bulldog Ollie is thought to be the first dog in the UK to be diagnosed with the disease.
Owner Julie Newman, from Harlow, said she is "hugely relieved" her pet survived the illness following a transfusion.
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"It was really touch-and-go if he would make it.
"He was really lethargic, he normally has so much energy but he just lost it, he went really strange and we noticed he had blood in his urine," she said.=read more on bbc link=http://www.bbc.co.uk/news/uk-england-essex-35831572