According to the Department of Health’s latest figures, cases of chlamydia jumped from 386 in 2009 to 463 in 2011.

The numbers for Ballarat and the surrounding district also show that other sexually transmissible infections like gonococcal infection have risen 27 per cent.

Eureka Medical and Dental Centre general practitioner, Dr Rodney Stobart, who has been in the medical field for 40 years, said that the numbers were alarming.

“In all my experience of practice I have never come across anything like it,” Dr Stobart said.

“The increase is significant; I am surprised there are not many more cases.”

Dr Stobart said if left undetected the disease could lead to infertility in women.

“I have been in Ballarat for 18 months,” Dr Stobart said.

“And I have seen quite an amount (of patients) ever since I have been here.

“I am seeing up to couple of patients a week.”

The disease, he said, could often be asymptomatic.

“Often the symptoms in both men and women could be nil,” Dr Stobart said.

“Sometimes they may have a discharge.”

Dr Stobart said sexually active individuals should have protected sex and get themselves screened regularly.

“It can be after four weeks of the contact for the test to show positive,” he said.

Department of Health spokesman Graeme Walker said rates of STIs were increasing, in particular for chlamydia.

“This could be due to many factors, such as the increase in awareness about the disease within the general community and, consequently, increased numbers of people being tested,” Mr Walker said.

“Or it may be because of the greater sensitivity of the tests or a genuine increase in prevalence.”

Mr Walker said if STIs were left undetected, then the consequences could be devastating.

“Chlamydia could lead to pelvic inflammatory disease which could cause inflammation of the fallopian tubes leading to infertility or chronic pelvic pain,” he said.

“Chlamydia is often asymptomatic so it is a silent infection in up to 85 per cent of women and men.”

However, he said, the disease was also among the easiest to diagnose and treat.