A top vet has told pet owners of the "only effective way of preventing" a highly-infectious disease affecting dogs that is sweeping the UK.
Known as parvovirus, the virus attacks the animal's digestive system and causes vomiting and bloody diarrhoea.
Last week, deadly outbreaks were recorded in Auckland, Australia, and cases have now been confirmed in the north of England.
Yorkshire Live reports that a "significant number" of dogs have tested positive for the virus after experiencing gastroenteritis-like symptoms.
It comes after reports of dogs are being struck down with a mystery illness leaving them lethargic and thin - with walkers saying pathways are covered in diarrhoea.
Parvovirus hit Britain in the 90s and a leading Yorkshire vet has told owners what to do if their pet falls unwell.
Director at Donaldson's Vets, Martin Paterson, who became famous appearing on Channel 5's The Yorkshire Vet, said: "We have been testing the majority of these cases for parvovirus and we have turned up a number of dogs who have tested positive.
"A lot of them are very ill and need quite a lot of intensive, inpatient management to be able to turn them around."
But he stressed dogs testing positive for the virus are not showing the "very, very acute signs" that made the virus so deadly in the late 1980s to 1990s.
He added: "It is difficult to be sure whether it is just a case of us testing more dogs for parvovirus, and that is reflecting what is going on more widely, or whether there is a unique issue in this area.
"We are seeing dogs that have been to the seaside - where a lot of these reports are coming from - but we are also seeing a lot of dogs with gastroenteritis who have stayed locally.
"We have not been able to find any pattern to connect these dogs. They are of all ages, all breeds and all geographical areas across the branches of our practice. The infections do seem to happen quite randomly."
According to Mr Paterson, symptoms of gastroenteritis among dogs include vomiting, diarrhoea, loss of appetite and an unwillingness to exercise.
He urged owners who notice such symptoms to seek medical attention immediately.
"Come and see us," he said. "We will often ask you to leave your dog in the car and we will examine them outside in the car park - just so that we're not risking bringing anything into the hospital or the clinic.
"There is a relatively quick test that we can do on faeces to check for parvovirus. This is not coronavirus - there is no evidence that it is connected to Covid in any way.
"Booster vaccinations for dogs need to be done every 12 months - so if your dog hasn't had their booster in that time, they are potentially susceptible to parvovirus."
He continued: "Parvovirus is very resistant and can survive in an environment for a long time. If you go out for a walk with your dog, keep them away from obvious piles of dog faeces.
"But, a dog could shed parvovirus on the path that you're walking on, and it can remain there for six months, so it is difficult to make sure that your dog doesn't come into contact with it.
"The only effective way of preventing it is booster vaccination."
Last week, Jennifer Griffin said her 15-month-old puppy fell violently ill a matter of hours after finishing a walk at the same park in Leeds.
She told Leeds Live : "He’s shaking, has a temperature, he’s vomiting loads, lethargic, not eating anything."
Just days earlier Nicola Jane said her dog, a six-month-old Lurcher, became extremely poorly just a few hours after a walk by a canal and she thought her pup might die.
She added: "He is a mess, he is like a skeleton he is that skinny. He lost that much weight.
"There was nothing on him, no life, he was limp, I thought he was gone, I thought I was losing him."
