A German veterinary clinic has trained sniffer dogs to detect the novel coronavirus in human saliva samples with 94% accuracy.

The dogs are conditioned to scent out the "corona odor" that comes from cells in infected people, said Esther Schalke, a vet at Germany's armed forces school for service dogs.

Filou, a 3-year-old Belgian Shepherd, and Joe Cocker, a 1-year-old Cocker Spaniel, are two of the dogs being trained at Hanover's University of Veterinary Medicine.

"We did a study where we had dogs sniffing samples from COVID-positive patients and we can say that they have a 94% probability in our study ... that they can sniff them out," said Holger Volk, head of the veterinary clinic.

"So dogs can really sniff out people with infections and without infections, as well as asymptomatic and symptomatic COVID patients," he added.

Stephan Weil, premier of Lower Saxony, the state of which Hanover is the capital, said he was impressed with the study and called for feasibility tests before the sniffer dogs are put to use in everyday life, such as on people attending concerts.

"We now need tests in selected events," Weil said.

In Finland, dogs trained to detect the novel coronavirus began sniffing passenger samples at Finland's Helsinki-Vantaa airport last September, in a pilot project alongside more usual testing at the airport.

Chile's Santiago international airport is also using canine detectors.