Australian Gonococcal Surveillance Programme Annual Report, 2018.

Abstract

The Australian Gonococcal Surveillance Programme (AGSP) has continuously monitored antimicrobial resistance in clinical isolates of Neisseria gonorrhoeae from all states and territories since 1981. In 2018, there were 9,006 clinical isolates of gonococci from public and private sector sources tested for in vitro antimicrobial susceptibility by standardised methods. This was the highest annual total of isolates tested since the inception of the AGSP. The current treatment recommendation for gonorrhoea, for the majority of Australia, remains dual therapy with ceftriaxone and azithromycin. Decreased susceptibility to ceftriaxone (minimum inhibitory concentration (MIC) value ≥0.06 mg/L) was found nationally in 1.73% of isolates. The highest proportions were reported from Tasmania and non-remote Western Australia (7.3% and 2.1% respectively). In 2018 two extensively drug-resistant isolates were reported from Queensland patients. These two isolates, with ceftriaxone MIC values of 0.50 mg/L, high-level resistance to azithromycin (MIC ≥ 256 mg/L), and resistance to penicillin and ciprofloxacin were identified and reported to the World Health Organization as isolates of international significance. Resistance to azithromycin (MIC value ≥1.0 mg/L) was found nationally in 6.2% of isolates, lower than the 9.3% reported in 2017, but more than double the proportion reported in 2015 (2.6%). The highest proportions were reported from the Australian Capital Territory (8.7%), Victoria (8.3%), and New South Wales (6.5%). High-level resistance to azithromycin (MIC value ≥256 mg/L) was reported in nine isolates nationally in 2018: four from New South Wales, three from Victoria, and two from Queensland. The proportion of isolates resistant to penicillin in non-remote Australia ranged from 8.8% in non-remote Northern Territory to 44.1% in South Australia. In remote Northern Territory penicillin resistance rates remain low (1.9%), and higher in remote Western Australia (6.5%). The proportion of isolates resistant to ciprofloxacin in non-remote Australia ranged from 10.3% in non-remote Northern Territory to 48.3% in South Australia. Ciprofloxacin resistance rates remain comparatively low in remote Northern Territory (1.9%) and remote Western Australia (4.6%).