Reports of an international racehorse testing positive to the equine influenza (EI) virus in Sydney are inaccurate, the Department of Agriculture, Fisheries and Forestry (DAFF) says.The racing industry was reportedly on high alert on Thursday, following a revelation the horse had tested positive for EI, News Limited reports.The test result on the horse was termed "ambiguous", but the department says it is not the same as a positive test."Some horses that recently arrived at Eastern Creek (Quaran

Reports of an international racehorse testing positive to the equine influenza (EI) virus in Sydney are inaccurate, the Department of Agriculture, Fisheries and Forestry (DAFF) says.

The racing industry was reportedly on high alert on Thursday, following a revelation the horse had tested positive for EI, News Limited reports.

The test result on the horse was termed "ambiguous", but the department says it is not the same as a positive test.

"Some horses that recently arrived at Eastern Creek (Quarantine Station) from the UK and the US had developed signs of a respiratory infection and testing to date indicates it is not EI," a statement from Australia's Chief Veterinary Officer Andy Carroll says.

The horses had tested positive to equine herpes virus 4, which causes a mild respiratory disease similar to a common cold but in horses.

"Equine herpes virus 4 is already present in Australia and most other countries, and is not a disease of quarantine concern."

Following the 2007 equine influenza outbreak, stronger biosecurity measures had been put in place at quarantine stations around the country.

Those horses showing signs of respiratory illness were subject to additional testing, and suspect horses were also tested for the presence of EI antibodies.

One horse showed an increase in antibodies since it arrived from overseas, however, "this does not represent a positive result for the presence of EI virus".

The fifth and final swab tests had been sent off for lab testing for all 23 horses that recently arrived from the US and UK.

The horses will be held in quarantine until the tests confirm they are EI-free.