"New Zealand has a similar health care system to those in the United Kingdom and Canada and we rate higher than both in cases per population."
Giola said reasons for this were numerous and diverse.
"The decline in use of condoms from the early 2000s, particularly since it became known that HIV was not a lethal disease and possibly caused relaxation in people, is one.
"Also things like Tinder [for heterosexuals] and Grindr [for gay, bi, trans and queer people] make it easy to find partners or see who is around looking for sex."
However, finger-pointing was easy, according to Giola, who also said there were more often structural and deep-rooted causes.
"In regions New Zealand where there is not abundant access to free sexual health services, we see higher STI numbers. There also remains a stigma around STIs which makes disclosure hard for some people."
Giola said he was "reasonably happy" with some of the initiatives introduced by the new Government after what he believed to have been 10 years of sexual health being out on the back burner.
"We are in desperate need of a national campaign promoting condom use and we also need to make sure people feel okay to talk to their GPs or a nurse or clinic staff. And every person who is sexually active needs to take part in regular screenings."
In New Zealand, chlamydia is not classified as a notifiable disease but is the most commonly reported STI, although the rates have remained stable since 2013.
Unlike syphilis and gonorrhoea, it was more widely reported by females although that was probably due to lower rates of testing in men, ESR public health physician Jill Sherwood said.
It was most common in women aged 15 to 29 with the highest rates among Māori and Pacific Islanders.
Auckland University's School of Population Health research fellow Dr Peter Saxton said while rising syphilis rate had been a problem for some years, it was a concern to see gonorrhoea rates rise 50 per cent in two years.
Of all the gonorrhoea cases where information was available, 34 per cent were among men who had sex with men despite the fact that group only comprised about 2 per cent of the population, he said.
"That's really alarming. That a third is among gay and bisexual men really is a shock," he said.
"The chickens are coming home to roost after a number of years of lack of strategic direction and underinvestment in sexual health programmes."
Saxton said more funding was needed to make services more available to all groups, in all areas; for education programmes; to hire more sexual health specialists; and to train GPs in how to identify and comprehensively care for the rainbow community in a non-judgmental way.
Syphilis
• The first sign of syphilis is a sore or ulcer at the site of infection, usually the genitals, anus or mouth. Untreated, it can lead to rashes, swollen glands, fever, hair loss, aches and warty growths.
• Late-stage syphilis can cause damage to the heart, brain, nerves, eye, blood vessels, liver, bones and joints.
• The disease is spread through sexual contact and is infectious if not treated with antibiotics.
Gonorrhoea
• In women, symptoms include unusual discharge, tummy pain, bleeding between periods and pain when urinating. In men, they include unusual discharge, irritation of the inside of the penis, sore testicles and pain when urinating.
• Without treatment if can lead to pelvic inflammatory disease, ectopic pregnancy, infertility and sterility.
• It is spread by skin contact during sexual intercourse and can be treated with antibiotics.
Chlamydia
• Most people with chlamydia have no symptoms but left untreated it can damage a women's reproductive system.
• However, in women, symptoms could include discoloured discharge, pelvic pain, bleeding between periods, pain during sex and rectal pain and bleeding. In men, symptoms could include discharge, sore testicles, pain urinating, pain during sex and rectal pain and bleeding.
• Chlamydia is spread by sexual contact and can be treated with antibiotics.
