Olympic officials insist that Hong Kong remains a suitable venue for the 2008 equestrian events despite the area's worst ever outbreak of equine herpes.
The Beijing Games will take place in August next year
A total of 132 horses have been infected in the past two months but the Hong Kong Jockey Club is confident the containment measures taken are working.
Olympic equestrian organisers say they are unworried because strict quarantine restrictions will be used in 2008.
"We will not be affected," insisted spokesman Christopher Yip.
The horses have fallen sick since 9 February, with symptoms of mild fever, blood problems and swelling in the legs.
But the Hong Kong Jockey Club said the sick horses recovered within a few days and most returned to training within a week.
"We've never had an outbreak involving so many horses," said spokesman Wilson Cheng.
"Even if you're vaccinated against the flu, it doesn't mean you're totally immune. You may get mild symptoms, but they can be quickly controlled."
Cheng said Jockey Club officials suspect the herpes spread by shared horse equipment.
The 2008 Olympic equestrian events were switched to Hong Kong from Beijing because of concerns about equine disease on the mainland.
The outbreak comes three weeks before the prestigious Queen Elizabeth II Cup race on 29 April, and as local police investigate how a 40-foot metal hose came to be embedded in the turf at the Happy Valley racecourse.
The apparent sabotage attempt caused shock in Hong Kong but organisers have insisted that security will be extremely tight for the 2008 events.