Chlamydia psittaci is a bacterium carried by birds. It can cause a respiratory disease in people called Psittacosis and has also been linked to abortion in mares.

Since the 2015 Stud Season, Scone Equine Hospital, the DPI, NSW Health and ESC have been conducting an investigation into the possible role of Chlamydia psittaci in equine abortion/stillbirth/neonatal illness.

Last year there was a small cluster of cases of Psittacosis in veterinary students who were involved in treating a sick neonatal foal at a university veterinary school.

This resulted in the DPI testing samples from equine abortions for Chlamydia psittaci.

The bacteria were detected in a small number of equine abortions in NSW last year and have again been detected in equine abortions this year, including some cases in the Hunter.

Because the bacteria have not been tested for prior to last year, it is unclear at this time whether Chlamydia is the cause of these abortions or is simply an incidental finding.

Due to the increased detection of Chlamydia in aborted equine foetuses in the last two years and the current investigation to determine the role of the bacteria in equine abortions, it is very important that we obtain as much information as possible about all abortions that occur.

We strongly encourage you to submit all aborted foetuses and membranes to the laboratory for routine testing (for Herpes Virus, EAFL, etc.) and to assess whether Chlamydia is a possible factor in the abortion.

As the relevance of these positive Chlamydia results in horses is currently unclear, we do not wish to cause unnecessary concern, however awareness of potential for human illness and the importance of hygiene procedures are obviously important.

Staff on studs and any people who come in contact with aborted material should be advised to undertake careful hygiene procedures when dealing with equine abortions/stillbirths/neonatal illness cases.

This should include wearing gloves and in particular, P2 masks when dealing with these cases.

Routine cleaning and disinfection of themselves and equipment is obviously very important.

People who have potentially been exposed are advised to seek medical attention if any of the symptoms apply and to advise their doctor of possible exposure to C. psittaci.

The disease can be treated with antibiotics.