Consistent with previous findings, sexual transmission accounts for the vast majority of new HIV diagnoses in New Zealand. Gay and bisexual men remain the population group most at risk of HIV. There had been a sharp increase in HIV transmission in New Zealand, but we have now had two consecutive years with a drop in transmissions.
Of the 178 diagnoses in 2018, 111 were among gay, bisexual and other men who have sex with men. Of these, 85 were first diagnosed in New Zealand and 26 had previously been diagnosed overseas. The number diagnosed and infected in New Zealand in 2018 was 60, which is 39% lower than in 2016.
27 people (18 men and 9 women) were infected through heterosexual contact in 2018. Of these, 17 were first diagnosed in New Zealand. HIV diagnoses among heterosexual people has remained relatively stable in New Zealand since 2010, the numbers being much smaller than those among gay, bi and other men who have sex with men.
One person was reported as having intravenous drug use as the only likely means of infection and one child born overseas was diagnosed with HIV in New Zealand. For the remaining 38 people the means of infection had not been recorded.
Overall, New Zealand has a relatively low prevalence of HIV by international standards. This is largely due to the consistent promotion, since 1987, of condom and lube use for anal sex between men. A robust legislative environment based on a strong human rights approach is also a key reason for this. However, the number of gay and bisexual men infected in New Zealand has been rising steadily since 2011. 2018 saw the second drop in the total number diagnosed. It is very likely this is a signal that modern prevention strategies such as Pre-exposure Prophylaxis (PrEP), Undetectable Viral Load (UVL), and a wider understanding and acceptance of testing and early treatment are contributing to the overall reduction, alongside the condom culture that NZAF has carefully cultivated over the years.
Low numbers of people who inject drugs (PWID) and the successful operation of an effective national needle exchange programme since 1988 has meant that PWID account for very few HIV infections in New Zealand. Similarly, the widespread adoption of condom use among New Zealand sex workers has resulted in a low rate of HIV transmission in the New Zealand sex industry. Widespread pregnancy screening and effective treatment for pregnant women means that the transmission of HIV from mothers to babies is at very low levels. These results are considered highly successful worldwide.
While gay and bisexual men account for only approximately 2.5% of New Zealand's population, they are consistently over-represented in HIV diagnoses. There are three clear reasons for this.
Annual HIV diagnoses in gay, bisexual and other men who have sex with men (MSM) New Zealand 1985-2018 (Red line)
In 2018, most gay and bisexual men diagnosed with HIV were again of European ethnicity.
In 2018 new diagnoses are again predominantly among gay and bisexual men who are under 40 (85%) - with the highest prevalence among those under 30 (36%).
Research conducted by Otago University in 2011 measured undiagnosed HIV among Auckland’s gay and bisexual men. Of the men who took part and were living with HIV, 1 in 5 (21%) did not know they had it. The study estimated that 1 in 15 (6.5%) gay and bisexual men in Auckland are living with HIV.
The annual number of heterosexual men and women infected in New Zealand has risen gradually since the mid-1990s, and for the last several years has remained just a little under the number infected overseas, although is still much smaller than the number of gay and bisexual men.
Annual HIV diagnoses in heterosexual men and women in New Zealand 1985-2018 (Blue line)
HIV diagnoses among heterosexual people infected overseas increased sharply from 2002 to 2006. This corresponds to a large increase in migrants and refugees between 2002 and 2004 from countries with a high prevalence of HIV. During this period, HIV screening was not a compulsory part of the immigration process in New Zealand. Heterosexual diagnoses began to decline from 2007 due to immigration policy changes in late 2005 which introduced mandatory HIV testing for residency applicants and people applying for visas for longer than 12 months.
Among all heterosexual men and women diagnosed with HIV in New Zealand, Africans remained the only ethnicity over-represented until 2015. In 2018, Asians too are over-represented with 30% of diagnoses among the Asian heterosexual population.
Direct blood to blood transmission is no longer a regular occurrence in New Zealand due to the work of the Needle Exchange Programme across the country. Only one person became infected with HIV as a result of injecting drug use in 2018.
It is widely acknowledged that there are very few sex workers in New Zealand with HIV. In fact, the latest published data in 2006 recorded there were no HIV infections among the study sample of more than 300 workers.
This is due, in large, to the work of the New Zealand Prostitutes Collective (NZPC). In operation since 1987, the NZPC is a nationwide community advocacy group focused on providing equal rights and safe working conditions for sex workers.
In 2018, one child was diagnosed with HIV infection through mother-to-child transmission in New Zealand, but the child was born overseas. Since 2007, there have been no children with perinatally-acquired HIV born in New Zealand. However, as diagnosis may be delayed for many years, there may be children living with undiagnosed infection born since or even earlier.
The AIDS Epidemiology Group (AEG) is based in the Department of Preventive and Social Medicine at the University of Otago. Since 1989 it has been responsible for national surveillance of AIDS and HIV infection in New Zealand.
The AEG epidemiological surveillance newsletters provide more detailed information about HIV and AIDS diagnoses in New Zealand.
The NZAF network