Nurses who helped immunise more than a million young New Zealanders during the MeNZB campaign last decade may have also helped reduce gonorrhoea rates.

The Lancet this week published New Zealand-led research that has found that the mass MeNZB vaccination programme of young New Zealanders between 2004-2008 has lead to a drop in cases of gonorrhoea, also known as ‘The Clap’ in vaccinated young Kiwis compared to those who weren’t vaccinated.

The study, lead by University of Auckland researcher Dr Helen Petousis-Harris, found that having the MeNZB vaccine reduced the incidence of gonorrhoea by about 31 per cent.

This is the first time a vaccine has shown any protection against gonorrhoea and the researchers say it may provide an avenue for developing a vaccine against the sexually transmitted infection (STI).

The study, funded by GSK vaccines, says that although meningoccal disease and gonorrhoea are very different diseases there is an 80 to 90 per cent genetic match between the bacteria that cause the diseases therefore providing a “biologically plausible mechanism for cross-protection”.

Gonorrhoea was once simply treated by an oral antibiotic but the development of antibiotic resistant strains means it now requires treatment by an intramuscular antibiotic plus an oral antibiotic.

The latest available STI statistics for New Zealand are from 2014 and, based on laboratory surveillance data, estimate that the national gonorrhoea rate is 70 cases per 100,000 people.  Nearly three-quarters of cases reported by laboratories are in people aged between 15 and 29 years old.

The Meningococcal B (MeNZB) vaccine was used as epidemic control vaccine after New Zealand noted from the late 1990s an increasing number of cases of meningococcal disease linked to one particular strain of meningococcal B bacterium. The mass public health campaign was launched in 2004 with anyone under the age of 20 offered the free MeNZB vaccine up until 2006. Routine immunisation for babies and preschoolers continued until June 2008.

The Ministry of Health reports that in all more than 1.1 million young New Zealanders received the MeNZB™ vaccine during this immunisation programme.  The number of people developing meningococcal disease due to the epidemic strain of meningococcal B reduced from over 300 cases in 2001 to less than 30 cases in 2010 but the disease has not entirely disappeared.

STUDY

Effectiveness of a group B outer membrane vesicle meningococcal vaccine against gonorrhoea in New Zealand: a retrospective case-control study

Published in The Lancet, July 10 2017

• Retrospective case-control study of patients at sexual health clinics aged 15–30 years born between Jan 1, 1984, and Dec 31, 1998
• All patients were eligible to receive MeNZB, and diagnosed with gonorrhoea or chlamydia, or both.
• The study analysed 14730 cases and controls
• There were 1241 incidences of gonorrhoea, 12,487 cases of chlamydia and more than 1000 cases of both.
• Vaccinated individuals were significantly less likely to be cases than controls (511 [41%] vs 6424 [51%]
• Estimate vaccine effectiveness of MeNZB against gonorrhoea after adjustment for ethnicity, deprivation, geographical area, and sex was 31%.
• The study was funded by GSK vaccines