A flu-like virus is forcing Vancouver's Hastings Racecourse to cancel this Saturday's horse races.

The first horses fell sick a week and a half ago, but the virus has since spread through the barn area and has now affected 150 horses.

Raj Mutti, regional general manager at Hastings Racecourse, says horses exhibit many of the same symptoms as people when they get sick.

They "get a cough, they will be sneezing, they will be very lethargic," he said.

Mutti says veterinarians are working overtime in the barn, but the horses still need rest and time to recover.

And while the flu typically affects horses every year, Mutti says this year is different.

"Usually it only affects the younger horses. The two-year-olds and the three-year-olds," he said. "This year its affected every horse. One of our top horses on the ground. She's eight [years old]."

Races scheduled for 7 p.m. PT Friday and 1:50 p.m. Sunday will proceed as scheduled. But two upcoming races will have to be cancelled.

Mutti says they will need to have enough thoroughbreds for the August 5 B.C. Day event — the biggest race day of the year.