Figure: Percentage of gonococcal isolates resistant to selected antimicrobials
The use of benzathine and procaine penicillin between the 1940s and 1970s led to a high level of penicillin resistance by the 1980s;
Tetracycline resistance in the UK was reported in 37% of cases by the 2000s;
Ciprofloxacin resistance was described at 22% in 2005;
Azithromycin resistance was observed in 9.8% of isolates sent to Public Health England in 2018.
Key: 1 = minimum inhibitory concentration (MIC) 2 = resistance breakpoints for azithromycin removed in 2019. Resistance was previously defined as >0.5 mg/L 3 = high-level azithromycin resistance is not defined by the European Committee on Antimicrobial Susceptibility Testing, but the definition in this figure is recognised internationally
Source: Sources: Whittles LK, White PJ, Paul J & Didelot X, Public Health England