Increase in incidence of infectious syphilis in Auckland, New Zealand: results from an enhanced surveillance survey

We instigated an enhanced voluntary surveillance system to determine the epidemiology of infectious syphilis in Auckland because it is not a notifiable condition. The study took place over a 12-month period from July 2006 to July 2007. We identified 92 cases of infectious syphilis, of which 71 were male (77%). Forty-four (48%) cases were in men who have sex with men, who made up the biggest proportion. Forty-eight cases (52%) acquired their infection in New Zealand and only 48 of all identified cases were symptomatic (52%). Our results confirm that infectious syphilis incidence is currently under-reported.