A vet at the animal charity PDSA's Sheffield animal hospital said it treated 30 to 40 per cent more pooches with the virulent virus last year than in 2015.
Parvovirus is a highly contagious illness, which affects dogs' intestines and in some cases hearts.
There is no treatment for the virus, which kills around a third of those infected, but there is a vaccine that must be topped up each year to remain effective.
Rob Haselgrove, senior veterinary surgeon at PDSA's Sheffield animal hospital, said only around two thirds of dogs in the UK had been vaccinated and the number was typically lower in less affluent areas.
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"The last year was particularly bad. We had a number of cases each day over the summer of dogs who were very, very sick with parvovirus," he told The Star.
"There were generally four or five hospitalised at any one time, which put a huge amount of strain on the hospital.
"It's distressing to see dogs dying from a disease that's easily preventable if owners get their pets vaccinated."
Mr Haselgrove said puppies should be vaccinated against parvovirus before being let out in public, unless they are taken outside in their owner's arms to acclimatise them to the new sights, noises and smells.
He said dogs must be given a booster each year to top up their protection, and he advised anyone in doubt to contact their vet.
While he accepted the £35 cost of the initial vaccination and £28 for booster injections could prove a stretch for those on tight budgets, he said this was much less than the hundreds of pounds they might have to shell out should their dog contract parvovirus.
Parvovirus infections typically dip over the winter, which Mr Haselgrove said was probably down to dogs being outside less and the virus not thriving as well in the cold.
But that has not stopped reports circulating on Facebook of parks which dog owners should avoid due to the disease.
Mr Haselgrove said he was not aware of any particular parks in the city where the risk was higher than others, and he advised owners the only way to be truly safe is to ensure your pet's vaccinations are up to date.
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