Researchers say a vaccine, originally developed to protect against a strain of meningitis, has been shown to ward off gonorrhea - a sexually transmitted infection.

The findings mark the first time a vaccine has shown any protection against gonorrhea and point to new avenues in the search for a specific vaccine to stop the global spread of 'super-gonorrhea'.

For their study, the researchers at the University of Auckland used data from 11 sexual health clinics for all people aged 15 to 30 who had been diagnosed with gonorrhea or chlamydia, or both, and who had also been eligible to be immunised against meningitis in the 2004-2006 campaign.

They found that those who had been vaccinated were significantly less likely to have gonorrhea.

According to they study, people who had received who had received the meningococcal B vaccine were 31 percent less likely to be infected with gonorrhea than those who hadn't received the MeNZB vaccine.

"This new research could be game-changing," said Linda Glennie, an expert at the Meningitis Research Foundation who was not directly involved in the study.

The findings "provide experimental evidence and a proof of principle" that meningitis vaccines might offer moderate cross-protection against gonorrhea," Helen Petousis-Harris, who co-led the study at the University of Auckland, said.

"Our findings could inform future vaccine development for both the meningococcal and gonorrhea vaccines," she added.

Despite the diseases being very different in symptoms and transmission modes, she added, the bacteria Neisseria gonorrhoeae and Neisseria meningitidis have an up to 90 percent genetic match, providing a biologically plausible mechanism.

Yet so far, efforts to develop a gonorrhea vaccine have yielded disappointing results: Four potential shots have reached the clinical trial stage, but none has been effective.

Gonorrhea has become an increasingly urgent global health problem in recent years as it is getting much harder and sometimes impossible to treat due to antibiotic resistance.

Because of this, the World Health Organization includes gonorrhea in its list of bacteria that pose the greatest threat to human health.

Each year, an estimated 78 million people are infected with gonorrhoea which can infect the genitals, rectum, and throat.

Complications of gonorrhoea disproportionally affect women, including pelvic inflammatory disease, ectopic pregnancy and infertility, as well as an increased risk of HIV.

The WHO said safer sexual behaviour, in particular consistent and correct condom use, can help prevent gonorrhoea.

The new findings have been published in The Lancet medical journal on Tuesday.