Police have issued tickets to two activists protesting the killing of hundreds of ringworm-infected animals at the York Region SPCA.

The protestors, who were detained and released after each received a $55 ticket for trespassing on Wednesday afternoon, returned to a crowd of dozens picketing outside the Newmarket, Ont. facility where officials have not been able to contain a ringworm outbreak among more than 300 cats and dogs.

Ringworm is a highly contagious fungal infection that is easily spread to humans. Six shelter workers have contracted ringworm and, in one instance, the infection has been passed on to a family.

CTV Toronto's Andria Case reported that 48 cats and two dogs have been put down so far.

OSPCA officials say that only the animals with the most severe cases are being put down, and it could take months before the outbreak is contained, Case reported.

In fact, officials aren't even sure if ringworm is the only illness afflicting the animals.

Still, protesters said that the OSPCA isn't doing enough.

Demonstrator Christine Condy said that she would have adopted an animal if she knew what was happening ahead of time.

"There's a German Sheppard in the back that has no symptoms at all," she said, adding that her other pets have been treated for ringworm.

"We've had ringworm. It's like athlete's foot, for heavens sake."

Premier Dalton McGuinty is backing the decision of experts to euthanize the sick pets.

"I know the decision to have a number of animals euthanized recently has been very, very difficult for those involved, painful for those who have to watch from the sidelines, but I think we have to have confidence in our experts," McGuinty said Wednesday.

Public outcry prompted shelter officials to isolate 20 of the infected animals in the hope that they may benefit from further treatment, but plans remain to euthanize other sick pets so that the infection does not spread.

MPP Frank Klees (Newmarket-Aurora) is calling on the government to stop animals from being put down.

"The Minister and this government continue to wash their hands," he said in the Legislature on Wednesday.

"I don't trust the SPCA, I don't trust the board. It's a wrong decision. Veterinarians across this province, animal rescue organizations across the province, ordinary citizens across the province are saying ‘let us be part of an alternative solution that will save the lives of these animals.'"

Dr. Jim Berry, a New Brunswick veterinarian and member of the Canadian Veterinary Medical Association, said it is extremely difficult to rid cats and dogs of ringworm when they live in a closed, warm, moist environment such as a shelter.

"In a shelter where we're dealing with dogs and cats which people know as pets, people are thinking individual animals. The reality is the medicine involved and the decisions involved often come down to a population basis," he said.

"It does not sound nice to depopulate or euthanize (about) 350 animals, but strictly speaking from a health perspective point of view, that may be the most humane, the most rational decision to be made."

Officials from both the Toronto and Durham Humane Societies decried the decision of the SPCA to euthanize the pets, pointing to their previous success containing outbreaks.

THS president Bob Hambley issued a news release suggesting that citizens petition the government.

"The THS has spoken out against the Ontario SPCA's decision to euthanize over 300 animals due to ringworm (a treatable fungal skin infection that is not fatal,)" he said