The advice to pet owners is to have their rabbits vaccinated against the disease.
The GSPCA has used social media to highlight the potential danger to domestic rabbits.
Myxomatosis is often seen in the wild rabbit population and the Shelter says there is currently an outbreak and a sharp rise in numbers affected.
Wild rabbits show symptoms of lethargy and the disease affects their eyes.
It is fatal to the majority of rabbits but does not transmit to humans.
The GSPCA say the outbreak could mean that it spreads to domesticated rabbits by an insect bite and this is why they advise vaccination.
They say most vets will provide a combination jab that also immunises the pet against RHD or Rabbit Haemorrhagic Disease.
The Shelter wants anyone who spots a wild rabbit with Myxomatosis to contact them.

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