Reader Lena Dobreci wrote to askST about the SPCA's warning, issued in March, about the high number of cases of the deadly disease known as canine parvovirus in Singapore.
She said: "There have been incidents of puppies infected that were purchased from pet store Fatty Paws. And last September there was an outbreak of canine parvovirus in the dog shelter SOSD. Should there be more government requirement for vaccination? What is being done to limit any further cases of this disease in Singapore?"
Environment reporter Audrey Tan answered the questions.
Canine parvovirus is a highly contagious disease that can cause death in animals such as dogs.
The disease affects only members of the canine family, such as dogs, wolves and foxes, and cannot be transmitted to humans.
But the owners of infected dogs can still be subject to emotional stress.
In March, a miniature white pomeranian puppy bought from Fatty Paws, a pet shop in Serangoon, died from the disease. It had vomited and passed blood in its faeces before it died.
The puppy's death prompted its owner, Ms Jorine Lim, 29, a manager at a beauty chain, to pen a Facebook post alleging that Fatty Paws did not take proper care of its puppies.
The Agri-Food and Veterinary Authority (AVA) is investigating the case.
It was not the only incident of parvovirus outbreak in Singapore. In 2013, an outbreak in animal welfare group SOSD's shelter infected more than 15 dogs and claimed three lives.
The disease infects the gastrointestinal tracts of dogs, especially puppies, and is transmitted either through contact with an infected dog, or contaminated surfaces, such as kennel surfaces, collars and leashes.
The virus is very resistant, and can survive in the environment for long periods, said the AVA. Symptoms include vomiting, bloody diarrhoea and rapid dehydration.
"Do not delay in taking your dog to the veterinarian if it displays these symptoms. There is no direct cure for the virus. Affected animals are provided with supportive care such as fluid therapy and medication to manage symptoms," said AVA.
To reduce the risk of dogs catching the disease, the AVA advises dog owners to vaccinate their dogs, and ensure that vaccinations are kept up-to-date.
Vaccinating pets reduces the risk of infectious diseases which may affect them, said an AVA spokesman.
According to AVA's licensing conditions, all pet shops must vaccinate puppies twice against canine distemper, parvovirus and infectious hepatitis before they are sold. These are core vaccinations as these diseases often cause suffering and may be potentially fatal.
AVA officers conduct unannounced routine inspections at pet shops in Singapore to ensure compliance to AVA’s licensing conditions, and to safeguard animal welfare and health.
While the authorities do not make it compulsary for shelter dogs to be vaccinated, animal welfare groups say they still do so.
Dr Siew Tuck Wah, president of SOSD, said: "It's voluntary, but it's good practice especially when the dogs are in a shelter in close proximity with one another."
Following the 2013 parvovirus outbreak in SOSD, Dr Siew said the shelter has adopted new strategies to safeguard the health of its dogs, including ensuring that new rescues are quarantined and kept in isolation before they are introduced to the rest of the dogs in its shelter.
Mr Derrick Tan, who heads another animal welfare group, Voices For Animals, added that most of its dogs have received annual vaccinations against a range of diseases, including parvovirus, leptospirosis and canine distemper. Only dogs that are too old are not vaccinated, as they may be too weak to withstand the effects.