HIV diagnoses fell almost 20 percent from 2016 to 2017, a new report shows, but the figure is being treated with caution.
In 2017, 197 people were diagnosed with HIV in New Zealand - almost 20 percent fewer than in 2016. 2016 was the worst year since records began, with 243 people diagnosed with HIV.
The research from the AIDS Epidemiology Group, based at the University of Otago and funded by the Ministry of Health, is being carefully celebrated.
AIDS Epidemiology Group leader Dr Sue McAllister said, "It's too early to say whether this decline will be maintained".
Associate Health Minister Julie Anne Genter said the reduction is "great news", though it was too early to say whether it was the beginning of a downward trend.
"I want to congratulate the hard work by the New Zealand AIDS Foundation for its community prevention work in this important area of public health," she said.
"I want to encourage all New Zealanders to continue to practice safe sex and to continue to encourage New Zealanders to get tested if they have been at risk."
Gay, bisexual and other men who have sex with men (MSM) were the group most affected according to the research.
Of the 197 people diagnosed, 128 were MSM and 24 were heterosexually infected (a similar number of men and women), one was infected through use of injected drugs and two were infected through mother-to-child transmission overseas.
The means of infection was not reported for the remaining amount.
Dr McAllister said changes to the management of people with HIV may have contributed to prevention of the disease.
"Now HIV-infected individuals are able to start treatment immediately on diagnosis...There is also now availability of pre-exposure prophylaxis [PrEP] to prevent infection for individuals at high risk of HIV."
She said the new measures, in addition to the use of condoms, regular and early HIV testing and treatment for other STIs all need to be utilised for New Zealand to see a continuing decline in diagnoses.
"It is also important that efforts are continuing to combat the stigma about HIV and the groups most affected, as when this exists testing could be discouraged, and people are less receptive to health promotion messages," she said.
New Zealand Aids Foundation (NZAF) executive director Dr Jason Myers said, "Any fall in the number of new HIV diagnoses should be celebrated but it is also very important to note that one data point is not a trend. We saw a similar drop from 2010 to 2011, and infection rates consistently rose from then until 2016. We need to see a steady consistent decrease over the next few years before we can confidently say we are on the right track."
Early last year the NZAF launched its awareness campaign Ending HIV, which aims to end HIV transmissions by 2025.
Dr Myers said there's no data to confirm whether the campaign is having a significant impact, as surveys to monitor the knowledge, attitudes and behaviours of gay and bisexual men have not been funded since 2014.
"Understanding changes in knowledge and behaviour since the introduction of treatment based prevention tools is critical if we are to ensure the most appropriate targeting of our behaviour change messaging," he said.
"It would also assist the Government in assessing whether NZAF's taxpayer-funded programs are having the desired impact."