Botanist David Bellamy has warned people not to sleep with their pets as they could be inviting bugs into their bed.
He urged pet owners to take more care with their dog or cat's hygiene to avoid coming into contact with a parasite which can cause them to go blind.
The Toxocara parasite lives in animal faeces but can survive even once owners have cleaned up after their pets, as it can stick to fur and be transferred to clothes or bedding.
About 40% of dog owners mistakenly believe they eliminate the risk of spreading the bug by scooping up their dog's excrement, Mr Bellamy said.
In fact, Toxocara is such a resilient parasite it takes a healthy dose of bleach to eradicate it completely from grass.
Mr Bellamy also said 52% of pet owners are happy to cuddle-up to their pets in bed or on the sofa, where they risk coming into contact with the parasite.
Veterinary scientist Steve Leonard also warned pet owners of the importance of maintaining animal hygiene.
"The usual suspects are fleas, ticks, lice and worms. We don't want to dissuade people from getting intimate with their pets, but they need to do some preventative care.
"Owners need to regularly de-flea and de-worm because if your pet is carrying a flea from outside it's going to be laying eggs in your bed.
"By the time you realise your pet has fleas it has probably already laid hundreds of eggs in your environment.
"They will hatch and sit for two years waiting for a warm body to come by, which can be yours and like a lot of biting insets, they can transmit disease such as scabies or mange."
But Bellamy and Leonard say owners should not start throwing their animals onto the street.
The risk of going blind from Toxocara infections is extremely rare and the bug is easily prevented in pets by regular de-worming.