Australia is expected to run out of Q fever vaccines this week.
The shortage is due to unexpected manufacturing issues.
It is hoped vaccines will be available again by the end of December.
The vaccine that protects Australians from a serious bacterial infection is expected to run out this week.
Q fever is spread by animals, including sheep and cattle, and causes severe flu-like symptoms that can become chronic and, in some cases, lead to serious cardiovascular complications.
Last year Australia recorded 991 Q fever cases; the highest number since national monitoring began in 1991
Australian manufacturer CSL Seqirus is contracted by Australia's Department of Health (ADH) to supply the vaccine.
"Unfortunately, we actually expect a short temporary stock out starting now through to the end of the year," senior vice-president of operations Chris Larkins said.
"We've expedited the next two batches that are being manufactured. They'll be available, we believe, late December.
"We are very sorry. We know it affects public health, especially in the country and also affects businesses financially out there."
Mr Larkins said stabilising supply was the company's highest priority "given how critical it is to public health and getting our agricultural businesses back up and functioning".
Rawsonville dairy owner Erika Chesworth said she had been unable to vaccinate her staff since March.
