The study tested 540 dogs and 277 cats living in households in northern Italy, particularly in Lombardy, where someone was infected with the virus or in areas where there were many cases.

The study, which has not been peer-reviewed yet, found coronavirus antibodies in 3.4 per cent of dogs and 3.9 per cent of cats, indicating they were infected with the virus.

Swab tests for active virus infections were negative in all animals, as the virus shedding period ended after two weeks. The tests were conducted between March and May of this year.

Thomas Mettenleiter, leader of the German Federal Research Institute for Animal Health (FLI), says the results show that the virus spreads between humans and animals.

"This confirms what we already know," Mettenleiter said, adding that the large scale of the study was unprecedented as it was difficult to get samples.

Most animals in the study came from households affected by the coronavirus, indicating that infection is generally transmitted from humans to animals, Mettenleiter said.

He added this confirmed the FLI's assumption that cats and dogs don't play a significant role in the spread of Covid-19, and that healthy people need not limit their contact with their pets.

People who are infected with the virus, however, should limit their contact with their pets, although there are no indications so far that animals can die of the coronavirus, according to Mettenleiter.

Australian Associated Press