Rates of new gonorrhoea diagnoses among Australians rose 63 percent in just five years, prompting health officials to urge sexually active people to get in the habit of having regular tests for sexually transmitted infections (STIs).

The Kirby Institute at the University of New South Wales released its Annual Surveillance Report on HIV, viral hepatitis and sexually transmissible infections in Australia.  It documents more than 23,800 new cases of gonorrhoea diagnosed in 2016.  About 75 percent of the new cases were among men, with the 20- to 29-year-old age group seeing the highest increase.  Among women, the biggest increase occurred in the 15- to 24-year-old range - but older age groups also saw increased numbers.

"The increase was most pronounced in the past two years," said The Kirby Institute's Rebecca Guy, who notes that it's happening in urban areas.  "Up until recently, gonorrhoea had been uncommon for young heterosexual people living in the major cities," she said.

Even though 80 percent of women and 50 percent of men won't have symptoms, gonorrhoea will still cause health problems.

"Left untreated, gonorrhoea is associated with serious long-term adverse health effects, including pelvic inflammatory disease, ectopic pregnancy and infertility," said Matthew Chico, assistant professor of public health at the London School of Hygiene & Tropical Medicine in an interview with CNN.  "Particularly concerning is that we are rapidly facing the day when gonorrhoea is no longer treatable due to antimicrobial resistance," he added.