A deadly strain of a common dog virus has reached Whitehorse, and taken at least four canine casualties so far.

Copper Road Veterinarian Clinic's Dr. Marina Alpeza, confirmed today, the clinic has taken in four dogs in the last few weeks suffering from fast-acting, deadly symptoms of parvovirus, known more commonly as parvo.

'Every year we have cases of parvo come in, but this is different,' she said. 'It's faster, more lethal.'

The new strain does not respond to the standard treatment of administering antibiotics and intravenous (IV) fluid.

'In most cases, the success rate with treatment is very high,' she said. 'Eighty to 90 per cent recover fully.'

Alpeza said the four dogs she has treated for the new strain of parvo have all died.

Alpeza said with all parvo cases, there is not a cure for the virus, but that veterinarians can only treat the symptoms of dehydration. She said most dog owners recognize the early signs of parvo.

'The dogs become lethargic, they stop eating,' she said. The dogs can then begin vomiting and have bloody diarrhea. These symptoms are still the telltale signs of the new strain, but the time that passes after the first appearance of symptoms is much faster.

'Usually it lasts five to seven days, but this is a lot faster,' she said. 'Two to three days altogether.'

Alpeza said three of the dogs with the new strain were from the Whitehorse area, with the other from Outside, travelling here with its owners.

Pet owners, she added, have reason to be alarmed about the new lethal strand of parvo, but can take steps to prevent their dogs from contracting the virus.

'These four cases, the dogs were not vaccinated,' said Alpeza.

Owners should vaccinate their puppies on a three-treatment schedule, with vaccinations at weeks nine, 12 and 16, then once annually after that.

Alpeza said many dog owners make the mistake of getting their dog vaccinated only once, thinking that was enough.

'I have not seen a case when a dog gets vaccinated and then gets parvo,' she said.

Parvo is contracted via feces, and the virus can live for up to 20 years in or on the soil, said Alpine Veterinary Medical Centre's Dr. Kim Friedenberg.

Dog owners should watch that both they and their dog does not get too close to other animal droppings when outside.

'Dogs can contract it from stepping on poop, or a person can carry it on their clothes,' said Alpeza.

She recommends cleaning any object that has come in contact with feces using bleach.

'We've found its the only thing that works for such a strong virus.'

Alpeza has been a veterinarian in the territory for 14 years, and said this new strain of parvo is a first for her.

'All four cases died, that's something we never see, in my 14 years I've never seen that.'