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What is now known as the acquired immune deficiency syndrome (AIDS) was first recognised as a clinical entity in 1981, and the first case diagnosed in New Zealand in 1983.1,2 The human immunodeficiency virus (HIV) was identified as the causative agent in 1984,3 and HIV antibody tests to detect infection became available in New Zealand in 1985.4Understanding the patterns of the epidemic in the population is important to develop appropriate preventive control and treatment services.5 To this end, AIDS was made a notifiable condition in 1983, however, HIV was not due to concerns this might discourage testing. Coded information on new diagnoses from the laboratories undertaking confirmatory testing for HIV antibodies has been available since this began.Epidemiological surveillance of AIDS and HIV was initially undertaken by the Department of Health, and since 1989 by the AIDS Epidemiology Group (AEG) based at the University of Otago, Dunedin. The AEGs surveillance has been centered on case reports of AIDS and newly diagnosed HIV infection, supplemented by HIV prevalence studies in sentinel populations. The AEG has also been involved in surveys of behaviours known to drive the spread of HIV and testing patterns.Collectively these three components are now known as Second Generation HIV Surveillance.6 While both diagnoses of AIDS and HIV infection are included in surveillance, since the introduction of effective antiretroviral treatment (ART) in the mid-1990s, the information obtained from AIDS notifications has been less valuable in understanding the epidemic of HIV infection than previously.The findings from the AEGs surveillance have been regularly reported in the newsletter AIDS New Zealand, but as there has been no recent published review of the New Zealand epidemic, we have taken opportunity of the 30th anniversary of HIV testing in New Zealand to review the current epidemiology.The aims of this article are therefore to (a) summarise key findings of the current epidemiology based on reports of diagnosed AIDS and HIV in New Zealand, (b) discuss how these, and findings from other sources, inform HIV care and prevention needs among particular groups in New Zealand, and (c) consider important areas for future epidemiological surveillance.MethodsAn individual with HIV infection is defined as having AIDS when he or she first develops one of a number of specific conditions uncommon in people with normal immunity. Clinicians diagnosing AIDS are required to make an unnamed coded notification to the Medical Officer of Health, which are then forwarded to the AEG; the code is based on the individuals initials, gender and date of birth. The information required includes key demographic characteristics, the AIDS-defining condition and likely means of infection.Since antibody testing for HIV infection first became available in New Zealand in 1985, the number of people newly diagnosed with HIV on the basis of a confirmatory Western Blot (WB) antibody test has been available from the two laboratories undertaking this testing, Auckland City Hospital Virology Laboratory and the Institute of Environmental Science and Research Limited, Porirua. These laboratories have provided the age, sex and likely means of infection of these people when it was provided to them.The information was sent initially to the Ministry of Health, and since 1989, to the AEG. As with AIDS, information is only supplied to the AEG by code and never identified by name. Since 1996, the AEG has undertaken enhanced surveillance of HIV, whereby further information is sought from the clinician who requested the test.7 The additional information includes the site of and reason for the test, the infected persons ethnic group, district of usual residence, and likely country of infection. The categorisation of the regions is based on the areas covered by the Regional Health Authorities that existed when surveillance of HIV was intensified in the 1990s, with the population of the Northern Region being mainly made up of people living in Auckland. From the beginning of 2002, the laboratories performing HIV viral load (VL) testing have provided the codes derived in the same ways as for AIDS notifications and HIV information of people having their first VL test in their laboratory. If it appears through linking of the code to the AEGs HIV database that a person having a VL test had not had a positive HIV antibody test in New Zealand, information is sought from the clinician who requested the VL test. This was established initially to gain information on people being cared for in New Zealand with HIV infections diagnosed overseas, without having had an antibody test in this country. However, VL testing has increasingly been used to confirm new HIV infections, so is now an important source of people being first diagnosed here.Since 2005, information on the initial CD4 cell count has been requested on people newly diagnosed with HIV infection in New Zealand;8 initially, this was only among those whose diagnosis was confirmed through WB testing, but subsequently through VL testing, if the infection was first diagnosed in New Zealand. The initial CD4 count gives an indication of the stage of the disease at diagnosis, and when less than 350 cells per cubic milliliter, it is considered a late diagnosis.To compare the recent epidemic among men who have sex with men (MSM) in New Zealand with that of other high-income countries, the annual diagnosis rate of HIV infection of MSM in selected countries were compared. These diagnosis rates were derived annually for each country from 2004-2013 using the number of diagnoses among MSM as the denominator and the number of men aged 15-64 as the numerator. Details of the method are reported in the Appendix.Information has been collected since 1998 from paediatricians, via the New Zealand Paediatric Surveillance Unit, on babies born to women with HIV diagnoses at the time of delivery.9We present and describe key findings on the reports of AIDS and diagnosed HIV infection. As this is a surveillance report, statistical testing is not undertaken. Where appropriate we have combined data reported over the five-year period 2010-2014 to give an indication of the current pattern of diagnoses.ResultsAIDSOverall, there have been 1,153 people notified with AIDS to the end of 2014 (Table 1). Just over two-thirds (67.2%) of notifications were among gay, bisexual and other MSM infected through homosexual contact, with men and women infected through heterosexual contact the second largest group (20.7%). The age at diagnosis ranged from less than one to 78 years of age, with a median of 39 years; although for most of these people, infection would have occurred at a younger age, as the median time from HIV infection to the development of AIDS is around ten years in untreated young adults, and shorter in older people.10Table 1: Gender, likely means of infection, age (at diagnosis), and ethnicity of people diagnosed with AIDS in 2010-2014 and <2010 and in total. 2010-2014 <2010 Total No. % No. % No. % Total 105 100.0 1,048 100.0 1,153 100.0 Gender Male 85 81.0 932 88.9 1,017 88.2 Female 20 19.0 113 10.8 133 11.5 Transgender 0 0.0 3 0.3 3 0.3 Likely means of infection Homosexual contact (MSM) 57 54.3 718 68.5 775 67.2 Homosexual (MSM) or IDU 1 1.0 14 1.3 15 1.3 Heterosexual contact 33 31.4 206 19.7 239 20.7 Injecting drug use (IDU) 1 1.0 24 2.3 25 2.2 Transfusion or blood product recipient 0 0.0 21 2.0 21 1.8 Mother to child transmission 0 0.0 18 1.7 18 1.6 Other 0 0.0 5 0.5 5 0.4 Unknown 13 12.3 42 4.0 55 4.8 Age at diagnosis (years) <5 0 0.0 12 1.1 12 1.0 5-14 0 0.0 10 1.0 10 0.9 15-19 0 0.0 4 0.4 4 0.3 20-29 9 8.6 159 15.2 168 14.6 30-39 21 20.0 399 38.1 420 36.4 40-49 41 39.0 298 28.4 339 29.4 50-59 20 19.1 123 11.7 143 12.4 > 60 14 13.3 40 3.8 54 4.7 Unknown 0 0.0 3 0.3 3 0.3 Ethnicity European 54 51.4 722 68.9 776 67.3 M\u0101ori 22 20.9 116 11.1 138 12.0 Pacific Islander 5 4.8 35 3.3 40 3.5 African 5 4.8 77 7.3 82 7.0 Asian 13 12.3 64 6.1 77 6.7 Other 5 4.8 27 2.8 32 2.8 Unknown 1 1.0 7 0.7 8 0.7 The annual number of diagnoses of AIDS, and deaths of people notified with AIDS, are shown in Figure 1. AIDS diagnoses peaked in 1989 and 1990 with 71 cases, and deaths in 1992 with 66. The dramatic drop in the number of diagnoses in the mid-1990s, which was seen in other high-income countries, is contemporaneous with the introduction of effective antiretroviral therapy (ART).Figure 1: Annual number of diagnoses of AIDS and deaths among people notified with AIDS As well as reducing the number of people with HIV infection progressing to AIDS, treatments available in the mid-1990s resulted in a marked improvement of the survival of people meeting the criteria for AIDS. As an indication of this, of those diagnosed with AIDS in New Zealand in 1990, less that 10% were still alive five years later, while this was the case for over 70% of people diagnosed a decade later in 2000.Ideally, people are diagnosed with HIV infection before developing serious infections that classify them as having AIDS. However in the period 2010-2014, 74.3% (78/105) had been diagnosed with HIV infection at same time or less than 3 months prior to developing AIDS-defining conditions. Among many of those, an earlier HIV diagnosis and prior ART could have avoided progression to AIDS, so earlier HIV diagnosis could be expected to reduce the annual number of AIDS notifications further.HIV infectionInformation obtained from the HIV testing laboratories indicates that 4,168 people have been diagnosed with HIV in New Zealand to the end of 2014 (Table 2). Of these, 3,452 were through positive WB antibody tests, and 716 through having VL tests among people not known by the AEG to have had a prior WB test. While scrutiny of codes have been used to detect duplicate reports, these have not always been provided, especially in the early years of testing, so some duplication cannot be ruled out.Table 2: Likely means of infection of people diagnosed with HIV in 2010-2014, <2010 and total. These figures include people previously diagnosed overseas. 2010-2014 <2010 Total No. % No. % No. % Total 883 100.0 3,286 100.0 4,168 100.0 Homosexual contact (MSM*) 543 61.4 1744 53.0 2,287 54.8 Homosexual contact (MSM*) or IDU 6 0.7 42 1.3 48 1.2 Heterosexual contact 209 23.7 897 27.3 1,106 26.5 Injecting drug use (IDU) 8 1.0 76 2.3 84 2.0 Blood product/transfusion recipient 0 0.0 62 1.9 62 1.5 Mother to child transmission 3 0.3 55 1.7 58 1.4 Other 7 0.8 32 1.0 39 1.0 Unknown/Not stated 107 12.1 378 11.5 484 11.6 *MSM - Men who have sex with menThe annual number of diagnoses by means of infection is shown in Figure 2. It is important to appreciate that for many, the year of diagnosis will not have been the same as when the infection occurred, so is not an indication of true annual incidence.As with AIDS, the majority (56.0%) of those diagnosed with HIV were MSM men infected through homosexual contact a small number of whom were also reported to have injected drugs (Table 2); the proportion rises to 63.4% if limited to those with a reported means of infection.The next largest group were heterosexually infected men and women, 26.4% of all diagnosed, and 30.0% of those with a reported means of infection. Notably few people have been definitely or possibly infected through injecting drug use. In 2010-2014, the proportion of diagnoses among MSM has increased to 70.7% of those with a known means of infection.Figure 2: Number of people diagnosed with HIV in New Zealand, by year of diagnosis and means of infection. These figures include people previously diagnosed overseas. Gay, bisexual and MSMOverall, there have been 2,335 MSM diagnosed with HIV. After an initial rise in the annual number in the late 1980s and early 1990s, the number dropped to a nadir in the late 1990s, with a subsequent rise in the early 2000s (Figure 2). While there was a steady increase in the years 2001 to 2005, since then the annual number has fluctuated. The highest ever annual number of MSM was diagnosed in 2014, and could indicate an upward trend in incidence, but it is too soon to conclude this. The overall rise since the early 2000s has been greatest among those infected in New Zealand rather than overseas (Figure 3).Figure 3: Place of infection of MSM first diagnosed with HIV in New Zealand by year of diagnosis, 1996-2014. These figures exclude people previously diagnosed overseas Although the median age for HIV diagnosis among MSM was 37 years, the range is wide, with the youngest being 16 and oldest, 78 years. As well as appreciating that these are the ages at diagnosis not infection, it needs to be kept in mind that this will not reflect the current age profile of MSM living with HIV, which will be older in view of the success of current treatments.The ethnic profile of MSM diagnosed in the five-years 2010-2014 (Table 3) is broadly similar to that of the male population aged 15-64 in the 2013 census. The higher proportion of an \u201cother\u201d ethnicity among HIV diagnoses is a reflection of people from overseas diagnosed here. The increase in recent years in the proportion of Asian people likely reflects the changing ethnic make-up of Auckland, where over 50% of newly diagnosed MSM and the HIV epidemic in MSM is concentrated (Table 3).Table 3: Characteristics of men who have had sex with men (MSM) diagnosed with HIV in 2010-2014, <2010 and total. These figures include people previously diagnosed overseas. 2010-2014 <2010 Total No. % No. % No. % Total 549 100.0 1,786 100.0 2,335 100.0 Age at diagnosis 15-19 11 2.0 34 1.9 45 2.0 20-29 142 25.9 468 26.2 610 26.1 30-39 151 27.5 652 36.5 803 34.4 40-49 148 27.0 382 21.4 530 23.0 50-59 64 11.7 155 8.7 219 9.1 60 or more 33 5.9 45 2.5 78 3.3 Unknown 0 0.0 50 2.8 50 2.1 Likely place of infection* New Zealand 353 64.3 655 58.2 1,008 60.2 Overseas 177 32.2 414 36.8 591 35.3 Unknown 19 3.5 57 5.0 76 4.5 Ethnicity* European 348 63.4 838 74.3 1,186 70.7 M\u0101ori 50 9.0 121 10.7 171 10.2 Pacific 19 3.5 36 3.2 55 3.3 Asian 84 15.3 77 6.8 161 9.6 African 0 0.0 7 0.6 7 0.4 Other 46 8.4 45 4.0 91 5.4 Unknown 2 0.4 4 0.4 6 0.4 Usual residence* New Zealand 516 94.0 1,030 91.3 1,546 92.2 Northern 303 58.7 528 51.3 831 53.7 Midland 41 7.9 137 13.3 178 11.5 Central 104 20.2 177 17.1 281 18.2 Southern 68 13.2 188 18.3 256 16.6 Overseas

Summary

Abstract

Aim

To summarise findings of the epidemiology of AIDS and HIV infection in New Zealand.

Method

Key results from reports of AIDS and diagnosed HIV infection are presented. Where appropriate, data on HIV diagnoses are reported for the period 2010-2014 to indicate the current pattern of diagnoses.

Results

New Zealand has a well-described low prevalence epidemic of HIV infection, mostly concentrated in sub-populations of men who have sex with men (MSM), and heterosexual individuals from sub-Saharan Africa and South-East Asia. The former is largely due to transmission within New Zealand, whereas the latter mostly occurred overseas, although the difference has been less marked in recent years. The number of notified cases of AIDS peaked in the late 1980s, and dropped dramatically in the mid-1990s due to the introduction of effective antiretroviral treatments. Presently, most cases of AIDS are in people with previously undiagnosed HIV infection. In contrast, currently the annual number of diagnoses of HIV infection is higher than in the late 1990s, due to more occurring among MSM. Over the past 30 years, each sub-epidemic has demonstrated a distinct pattern, reflecting different determinants. HIV among people who inject drugs, sex workers, children and the general population has been restricted to very low levels.

Conclusion

Control of HIV in New Zealand is favourable compared to many countries, however challenges remain, especially in prevention among MSM, and more timely diagnosis for all, especially those heterosexually infected. National monitoring of the clinical outcomes of people diagnosed with HIV would provide an indication of the provision of effective care and allow international benchmarking.

Author Information

- Nigel Dickson, Department of Preventive and Social Medicine, University of Otago, Dunedin; Bible Lee, Preventive and Social Medicine, University of Otago, Dunedin; Timothy Foster, Department of Preventive and Social Medicine, University of Otago, Dunedin; Peter Saxton, Social and Community Health, University of Auckland, Auckland. -

Acknowledgements

Correspondence

Nigel Dickson, Department of Preventive and Social Medicine, University of Otago, Dunedin

Correspondence Email

nigel.dickson@otago.ac.nz

Competing Interests

'- - Centers for Disease Control. Kaposis sarcoma and pneumocystis pneumonia among homosexual men - New York City and California. MMWR 1981;30:305-8 Romeril KR. Acute HTLV III infection (letter). NZ Med J 1985;98:401 Gallo RC, Montagnier L. AIDS in 1988. Scientific American 1988;259:40-48 Carlson RV, Skegg DC, Paul C, Spears GF. Occurrence of AIDS in New Zealand: the first seven years. MRC AIDS Epidemiology Group. NZ Med J 1991;101:131-134 World Health Organization. Consolidated strategic information guidelines for HIV in the health sector. Switzerland: World health Organization. Available from: http://apps.who.int/iris/bitstream/10665/164716/1/9789241508759_eng.pd f?ua=1&ua=1 World Health Organization and Joint United Nations Programme on HIV/AIDS. Guidelines for Second Generation HIV Surveillance. World Health Organization and Joint United Nations Programme on HIV/AIDS, Geneva 2000. Paul C, Wilson M, Dickson N, Sharples K, Skegg DC. Enhanced surveillance of HIV infections in New Zealand, 1996-1998. NZ Med J 2000;113:390-394 Dickson NP, McAllister S, Sharples K, Paul, C. Late presentation of HIV infection among adults in New Zealand: 2005-2010. HIV Med 2012;13:182-189 Dickson N, Paul C, Wilkinson L, Voss L, Rowley S. Estimates of HIV prevalence among pregnant women in New Zealand. NZ Public Health Reports 2002;9:17-19 Bacchetti P, Moss AR. Incubation period of AIDS in San Francisco. Nature 1989;338:251-­3 Ministry of Health. Country Progress Report New Zealand (HIV/AIDS) 2014. Wellington, New Zealand. Available from: http://www.health.govt.nz/publication/country-progress-­report-­new-­zealand-­hiv-­aids-­2014 Curtis H, Yin Z, Clay K, Brown AE, Delpech VC, Ong E. People with diagnosed HIV infection not attending for specialist clinical care: UK national review. BMC Infect Dis 2015;15:315 Saxton PJ, Dickson NP, Griffiths R, Hughes AJ, Rowden J. Actual and undiagnosed HIV prevalence in a community sample of men who have sex with men in Auckland, New Zealand. BMC Public Health 2012;12:92 Saxton P, Dickson NP, McAllister S, Sharples K, Hughes A. Increase in HIV diagnoses among homosexual men in New Zealand from a stable low period. Sex Health 2011;8:311-318 Saxton P, Dickson N, Hughes A. Location-based HIV behavioural surveillance among MSM in Auckland, New Zealand 2002-2011: Condom use stable and more HIV testing. Sex Transm Infect 2014;90:133-138 Psutka R, Dickson N, Azariah S, Couglan E, Kennedy J, Morgan J, Perkins N. Enhanced surveillance of infectious syphilis in New Zealand Sexual Health Clinics. International Journal of STD & AIDS, 2013;24:791-798 Henderson C, Brunton C, Lauzon C. Final Report of the National Needle Exchange Blood-borne Virus Seroprevalence Survey [BBVNEX2009] to the New Zealand Ministry of Health. 2011. Unpublished report to the Ministry of Health Gardner EM, McLees MP. Steiner JF, del Rio C, & Burman WJ. The spectrum of engagement in HIV care and its relevance to test-and-treat strategies for prevention of HIV infection. Clinical infectious diseases, 2011;52:793-800 Raymond A, Hill A, Pozniak A. Large disparities in HIV treatment cascades between eight European and high-income countries-analysis of break points. Conference presentation at HIV Drug Therapy Glasgow Congress, 2014. Journal of the International AIDS Society 2014, 17(Suppl 3):19507 Cleveland WS. LOWESS: A program for smoothing scatterplots by robust locally weighted regression. Am Stat 1981;35:54 R Core Team. R: A language and environment for statistical computing. R Core Team. Vienna, Austria 2012.- -

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What is now known as the acquired immune deficiency syndrome (AIDS) was first recognised as a clinical entity in 1981, and the first case diagnosed in New Zealand in 1983.1,2 The human immunodeficiency virus (HIV) was identified as the causative agent in 1984,3 and HIV antibody tests to detect infection became available in New Zealand in 1985.4Understanding the patterns of the epidemic in the population is important to develop appropriate preventive control and treatment services.5 To this end, AIDS was made a notifiable condition in 1983, however, HIV was not due to concerns this might discourage testing. Coded information on new diagnoses from the laboratories undertaking confirmatory testing for HIV antibodies has been available since this began.Epidemiological surveillance of AIDS and HIV was initially undertaken by the Department of Health, and since 1989 by the AIDS Epidemiology Group (AEG) based at the University of Otago, Dunedin. The AEGs surveillance has been centered on case reports of AIDS and newly diagnosed HIV infection, supplemented by HIV prevalence studies in sentinel populations. The AEG has also been involved in surveys of behaviours known to drive the spread of HIV and testing patterns.Collectively these three components are now known as Second Generation HIV Surveillance.6 While both diagnoses of AIDS and HIV infection are included in surveillance, since the introduction of effective antiretroviral treatment (ART) in the mid-1990s, the information obtained from AIDS notifications has been less valuable in understanding the epidemic of HIV infection than previously.The findings from the AEGs surveillance have been regularly reported in the newsletter AIDS New Zealand, but as there has been no recent published review of the New Zealand epidemic, we have taken opportunity of the 30th anniversary of HIV testing in New Zealand to review the current epidemiology.The aims of this article are therefore to (a) summarise key findings of the current epidemiology based on reports of diagnosed AIDS and HIV in New Zealand, (b) discuss how these, and findings from other sources, inform HIV care and prevention needs among particular groups in New Zealand, and (c) consider important areas for future epidemiological surveillance.MethodsAn individual with HIV infection is defined as having AIDS when he or she first develops one of a number of specific conditions uncommon in people with normal immunity. Clinicians diagnosing AIDS are required to make an unnamed coded notification to the Medical Officer of Health, which are then forwarded to the AEG; the code is based on the individuals initials, gender and date of birth. The information required includes key demographic characteristics, the AIDS-defining condition and likely means of infection.Since antibody testing for HIV infection first became available in New Zealand in 1985, the number of people newly diagnosed with HIV on the basis of a confirmatory Western Blot (WB) antibody test has been available from the two laboratories undertaking this testing, Auckland City Hospital Virology Laboratory and the Institute of Environmental Science and Research Limited, Porirua. These laboratories have provided the age, sex and likely means of infection of these people when it was provided to them.The information was sent initially to the Ministry of Health, and since 1989, to the AEG. As with AIDS, information is only supplied to the AEG by code and never identified by name. Since 1996, the AEG has undertaken enhanced surveillance of HIV, whereby further information is sought from the clinician who requested the test.7 The additional information includes the site of and reason for the test, the infected persons ethnic group, district of usual residence, and likely country of infection. The categorisation of the regions is based on the areas covered by the Regional Health Authorities that existed when surveillance of HIV was intensified in the 1990s, with the population of the Northern Region being mainly made up of people living in Auckland. From the beginning of 2002, the laboratories performing HIV viral load (VL) testing have provided the codes derived in the same ways as for AIDS notifications and HIV information of people having their first VL test in their laboratory. If it appears through linking of the code to the AEGs HIV database that a person having a VL test had not had a positive HIV antibody test in New Zealand, information is sought from the clinician who requested the VL test. This was established initially to gain information on people being cared for in New Zealand with HIV infections diagnosed overseas, without having had an antibody test in this country. However, VL testing has increasingly been used to confirm new HIV infections, so is now an important source of people being first diagnosed here.Since 2005, information on the initial CD4 cell count has been requested on people newly diagnosed with HIV infection in New Zealand;8 initially, this was only among those whose diagnosis was confirmed through WB testing, but subsequently through VL testing, if the infection was first diagnosed in New Zealand. The initial CD4 count gives an indication of the stage of the disease at diagnosis, and when less than 350 cells per cubic milliliter, it is considered a late diagnosis.To compare the recent epidemic among men who have sex with men (MSM) in New Zealand with that of other high-income countries, the annual diagnosis rate of HIV infection of MSM in selected countries were compared. These diagnosis rates were derived annually for each country from 2004-2013 using the number of diagnoses among MSM as the denominator and the number of men aged 15-64 as the numerator. Details of the method are reported in the Appendix.Information has been collected since 1998 from paediatricians, via the New Zealand Paediatric Surveillance Unit, on babies born to women with HIV diagnoses at the time of delivery.9We present and describe key findings on the reports of AIDS and diagnosed HIV infection. As this is a surveillance report, statistical testing is not undertaken. Where appropriate we have combined data reported over the five-year period 2010-2014 to give an indication of the current pattern of diagnoses.ResultsAIDSOverall, there have been 1,153 people notified with AIDS to the end of 2014 (Table 1). Just over two-thirds (67.2%) of notifications were among gay, bisexual and other MSM infected through homosexual contact, with men and women infected through heterosexual contact the second largest group (20.7%). The age at diagnosis ranged from less than one to 78 years of age, with a median of 39 years; although for most of these people, infection would have occurred at a younger age, as the median time from HIV infection to the development of AIDS is around ten years in untreated young adults, and shorter in older people.10Table 1: Gender, likely means of infection, age (at diagnosis), and ethnicity of people diagnosed with AIDS in 2010-2014 and <2010 and in total. 2010-2014 <2010 Total No. % No. % No. % Total 105 100.0 1,048 100.0 1,153 100.0 Gender Male 85 81.0 932 88.9 1,017 88.2 Female 20 19.0 113 10.8 133 11.5 Transgender 0 0.0 3 0.3 3 0.3 Likely means of infection Homosexual contact (MSM) 57 54.3 718 68.5 775 67.2 Homosexual (MSM) or IDU 1 1.0 14 1.3 15 1.3 Heterosexual contact 33 31.4 206 19.7 239 20.7 Injecting drug use (IDU) 1 1.0 24 2.3 25 2.2 Transfusion or blood product recipient 0 0.0 21 2.0 21 1.8 Mother to child transmission 0 0.0 18 1.7 18 1.6 Other 0 0.0 5 0.5 5 0.4 Unknown 13 12.3 42 4.0 55 4.8 Age at diagnosis (years) <5 0 0.0 12 1.1 12 1.0 5-14 0 0.0 10 1.0 10 0.9 15-19 0 0.0 4 0.4 4 0.3 20-29 9 8.6 159 15.2 168 14.6 30-39 21 20.0 399 38.1 420 36.4 40-49 41 39.0 298 28.4 339 29.4 50-59 20 19.1 123 11.7 143 12.4 > 60 14 13.3 40 3.8 54 4.7 Unknown 0 0.0 3 0.3 3 0.3 Ethnicity European 54 51.4 722 68.9 776 67.3 M\u0101ori 22 20.9 116 11.1 138 12.0 Pacific Islander 5 4.8 35 3.3 40 3.5 African 5 4.8 77 7.3 82 7.0 Asian 13 12.3 64 6.1 77 6.7 Other 5 4.8 27 2.8 32 2.8 Unknown 1 1.0 7 0.7 8 0.7 The annual number of diagnoses of AIDS, and deaths of people notified with AIDS, are shown in Figure 1. AIDS diagnoses peaked in 1989 and 1990 with 71 cases, and deaths in 1992 with 66. The dramatic drop in the number of diagnoses in the mid-1990s, which was seen in other high-income countries, is contemporaneous with the introduction of effective antiretroviral therapy (ART).Figure 1: Annual number of diagnoses of AIDS and deaths among people notified with AIDS As well as reducing the number of people with HIV infection progressing to AIDS, treatments available in the mid-1990s resulted in a marked improvement of the survival of people meeting the criteria for AIDS. As an indication of this, of those diagnosed with AIDS in New Zealand in 1990, less that 10% were still alive five years later, while this was the case for over 70% of people diagnosed a decade later in 2000.Ideally, people are diagnosed with HIV infection before developing serious infections that classify them as having AIDS. However in the period 2010-2014, 74.3% (78/105) had been diagnosed with HIV infection at same time or less than 3 months prior to developing AIDS-defining conditions. Among many of those, an earlier HIV diagnosis and prior ART could have avoided progression to AIDS, so earlier HIV diagnosis could be expected to reduce the annual number of AIDS notifications further.HIV infectionInformation obtained from the HIV testing laboratories indicates that 4,168 people have been diagnosed with HIV in New Zealand to the end of 2014 (Table 2). Of these, 3,452 were through positive WB antibody tests, and 716 through having VL tests among people not known by the AEG to have had a prior WB test. While scrutiny of codes have been used to detect duplicate reports, these have not always been provided, especially in the early years of testing, so some duplication cannot be ruled out.Table 2: Likely means of infection of people diagnosed with HIV in 2010-2014, <2010 and total. These figures include people previously diagnosed overseas. 2010-2014 <2010 Total No. % No. % No. % Total 883 100.0 3,286 100.0 4,168 100.0 Homosexual contact (MSM*) 543 61.4 1744 53.0 2,287 54.8 Homosexual contact (MSM*) or IDU 6 0.7 42 1.3 48 1.2 Heterosexual contact 209 23.7 897 27.3 1,106 26.5 Injecting drug use (IDU) 8 1.0 76 2.3 84 2.0 Blood product/transfusion recipient 0 0.0 62 1.9 62 1.5 Mother to child transmission 3 0.3 55 1.7 58 1.4 Other 7 0.8 32 1.0 39 1.0 Unknown/Not stated 107 12.1 378 11.5 484 11.6 *MSM - Men who have sex with menThe annual number of diagnoses by means of infection is shown in Figure 2. It is important to appreciate that for many, the year of diagnosis will not have been the same as when the infection occurred, so is not an indication of true annual incidence.As with AIDS, the majority (56.0%) of those diagnosed with HIV were MSM men infected through homosexual contact a small number of whom were also reported to have injected drugs (Table 2); the proportion rises to 63.4% if limited to those with a reported means of infection.The next largest group were heterosexually infected men and women, 26.4% of all diagnosed, and 30.0% of those with a reported means of infection. Notably few people have been definitely or possibly infected through injecting drug use. In 2010-2014, the proportion of diagnoses among MSM has increased to 70.7% of those with a known means of infection.Figure 2: Number of people diagnosed with HIV in New Zealand, by year of diagnosis and means of infection. These figures include people previously diagnosed overseas. Gay, bisexual and MSMOverall, there have been 2,335 MSM diagnosed with HIV. After an initial rise in the annual number in the late 1980s and early 1990s, the number dropped to a nadir in the late 1990s, with a subsequent rise in the early 2000s (Figure 2). While there was a steady increase in the years 2001 to 2005, since then the annual number has fluctuated. The highest ever annual number of MSM was diagnosed in 2014, and could indicate an upward trend in incidence, but it is too soon to conclude this. The overall rise since the early 2000s has been greatest among those infected in New Zealand rather than overseas (Figure 3).Figure 3: Place of infection of MSM first diagnosed with HIV in New Zealand by year of diagnosis, 1996-2014. These figures exclude people previously diagnosed overseas Although the median age for HIV diagnosis among MSM was 37 years, the range is wide, with the youngest being 16 and oldest, 78 years. As well as appreciating that these are the ages at diagnosis not infection, it needs to be kept in mind that this will not reflect the current age profile of MSM living with HIV, which will be older in view of the success of current treatments.The ethnic profile of MSM diagnosed in the five-years 2010-2014 (Table 3) is broadly similar to that of the male population aged 15-64 in the 2013 census. The higher proportion of an \u201cother\u201d ethnicity among HIV diagnoses is a reflection of people from overseas diagnosed here. The increase in recent years in the proportion of Asian people likely reflects the changing ethnic make-up of Auckland, where over 50% of newly diagnosed MSM and the HIV epidemic in MSM is concentrated (Table 3).Table 3: Characteristics of men who have had sex with men (MSM) diagnosed with HIV in 2010-2014, <2010 and total. These figures include people previously diagnosed overseas. 2010-2014 <2010 Total No. % No. % No. % Total 549 100.0 1,786 100.0 2,335 100.0 Age at diagnosis 15-19 11 2.0 34 1.9 45 2.0 20-29 142 25.9 468 26.2 610 26.1 30-39 151 27.5 652 36.5 803 34.4 40-49 148 27.0 382 21.4 530 23.0 50-59 64 11.7 155 8.7 219 9.1 60 or more 33 5.9 45 2.5 78 3.3 Unknown 0 0.0 50 2.8 50 2.1 Likely place of infection* New Zealand 353 64.3 655 58.2 1,008 60.2 Overseas 177 32.2 414 36.8 591 35.3 Unknown 19 3.5 57 5.0 76 4.5 Ethnicity* European 348 63.4 838 74.3 1,186 70.7 M\u0101ori 50 9.0 121 10.7 171 10.2 Pacific 19 3.5 36 3.2 55 3.3 Asian 84 15.3 77 6.8 161 9.6 African 0 0.0 7 0.6 7 0.4 Other 46 8.4 45 4.0 91 5.4 Unknown 2 0.4 4 0.4 6 0.4 Usual residence* New Zealand 516 94.0 1,030 91.3 1,546 92.2 Northern 303 58.7 528 51.3 831 53.7 Midland 41 7.9 137 13.3 178 11.5 Central 104 20.2 177 17.1 281 18.2 Southern 68 13.2 188 18.3 256 16.6 Overseas

Summary

Abstract

Aim

To summarise findings of the epidemiology of AIDS and HIV infection in New Zealand.

Method

Key results from reports of AIDS and diagnosed HIV infection are presented. Where appropriate, data on HIV diagnoses are reported for the period 2010-2014 to indicate the current pattern of diagnoses.

Results

New Zealand has a well-described low prevalence epidemic of HIV infection, mostly concentrated in sub-populations of men who have sex with men (MSM), and heterosexual individuals from sub-Saharan Africa and South-East Asia. The former is largely due to transmission within New Zealand, whereas the latter mostly occurred overseas, although the difference has been less marked in recent years. The number of notified cases of AIDS peaked in the late 1980s, and dropped dramatically in the mid-1990s due to the introduction of effective antiretroviral treatments. Presently, most cases of AIDS are in people with previously undiagnosed HIV infection. In contrast, currently the annual number of diagnoses of HIV infection is higher than in the late 1990s, due to more occurring among MSM. Over the past 30 years, each sub-epidemic has demonstrated a distinct pattern, reflecting different determinants. HIV among people who inject drugs, sex workers, children and the general population has been restricted to very low levels.

Conclusion

Control of HIV in New Zealand is favourable compared to many countries, however challenges remain, especially in prevention among MSM, and more timely diagnosis for all, especially those heterosexually infected. National monitoring of the clinical outcomes of people diagnosed with HIV would provide an indication of the provision of effective care and allow international benchmarking.

Author Information

- Nigel Dickson, Department of Preventive and Social Medicine, University of Otago, Dunedin; Bible Lee, Preventive and Social Medicine, University of Otago, Dunedin; Timothy Foster, Department of Preventive and Social Medicine, University of Otago, Dunedin; Peter Saxton, Social and Community Health, University of Auckland, Auckland. -

Acknowledgements

Correspondence

Nigel Dickson, Department of Preventive and Social Medicine, University of Otago, Dunedin

Correspondence Email

nigel.dickson@otago.ac.nz

Competing Interests

'- - Centers for Disease Control. Kaposis sarcoma and pneumocystis pneumonia among homosexual men - New York City and California. MMWR 1981;30:305-8 Romeril KR. Acute HTLV III infection (letter). NZ Med J 1985;98:401 Gallo RC, Montagnier L. AIDS in 1988. Scientific American 1988;259:40-48 Carlson RV, Skegg DC, Paul C, Spears GF. Occurrence of AIDS in New Zealand: the first seven years. MRC AIDS Epidemiology Group. NZ Med J 1991;101:131-134 World Health Organization. Consolidated strategic information guidelines for HIV in the health sector. Switzerland: World health Organization. Available from: http://apps.who.int/iris/bitstream/10665/164716/1/9789241508759_eng.pd f?ua=1&ua=1 World Health Organization and Joint United Nations Programme on HIV/AIDS. Guidelines for Second Generation HIV Surveillance. World Health Organization and Joint United Nations Programme on HIV/AIDS, Geneva 2000. Paul C, Wilson M, Dickson N, Sharples K, Skegg DC. Enhanced surveillance of HIV infections in New Zealand, 1996-1998. NZ Med J 2000;113:390-394 Dickson NP, McAllister S, Sharples K, Paul, C. Late presentation of HIV infection among adults in New Zealand: 2005-2010. HIV Med 2012;13:182-189 Dickson N, Paul C, Wilkinson L, Voss L, Rowley S. Estimates of HIV prevalence among pregnant women in New Zealand. NZ Public Health Reports 2002;9:17-19 Bacchetti P, Moss AR. Incubation period of AIDS in San Francisco. Nature 1989;338:251-­3 Ministry of Health. Country Progress Report New Zealand (HIV/AIDS) 2014. Wellington, New Zealand. Available from: http://www.health.govt.nz/publication/country-progress-­report-­new-­zealand-­hiv-­aids-­2014 Curtis H, Yin Z, Clay K, Brown AE, Delpech VC, Ong E. People with diagnosed HIV infection not attending for specialist clinical care: UK national review. BMC Infect Dis 2015;15:315 Saxton PJ, Dickson NP, Griffiths R, Hughes AJ, Rowden J. Actual and undiagnosed HIV prevalence in a community sample of men who have sex with men in Auckland, New Zealand. BMC Public Health 2012;12:92 Saxton P, Dickson NP, McAllister S, Sharples K, Hughes A. Increase in HIV diagnoses among homosexual men in New Zealand from a stable low period. Sex Health 2011;8:311-318 Saxton P, Dickson N, Hughes A. Location-based HIV behavioural surveillance among MSM in Auckland, New Zealand 2002-2011: Condom use stable and more HIV testing. Sex Transm Infect 2014;90:133-138 Psutka R, Dickson N, Azariah S, Couglan E, Kennedy J, Morgan J, Perkins N. Enhanced surveillance of infectious syphilis in New Zealand Sexual Health Clinics. International Journal of STD & AIDS, 2013;24:791-798 Henderson C, Brunton C, Lauzon C. Final Report of the National Needle Exchange Blood-borne Virus Seroprevalence Survey [BBVNEX2009] to the New Zealand Ministry of Health. 2011. Unpublished report to the Ministry of Health Gardner EM, McLees MP. Steiner JF, del Rio C, & Burman WJ. The spectrum of engagement in HIV care and its relevance to test-and-treat strategies for prevention of HIV infection. Clinical infectious diseases, 2011;52:793-800 Raymond A, Hill A, Pozniak A. Large disparities in HIV treatment cascades between eight European and high-income countries-analysis of break points. Conference presentation at HIV Drug Therapy Glasgow Congress, 2014. Journal of the International AIDS Society 2014, 17(Suppl 3):19507 Cleveland WS. LOWESS: A program for smoothing scatterplots by robust locally weighted regression. Am Stat 1981;35:54 R Core Team. R: A language and environment for statistical computing. R Core Team. Vienna, Austria 2012.- -

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What is now known as the acquired immune deficiency syndrome (AIDS) was first recognised as a clinical entity in 1981, and the first case diagnosed in New Zealand in 1983.1,2 The human immunodeficiency virus (HIV) was identified as the causative agent in 1984,3 and HIV antibody tests to detect infection became available in New Zealand in 1985.4Understanding the patterns of the epidemic in the population is important to develop appropriate preventive control and treatment services.5 To this end, AIDS was made a notifiable condition in 1983, however, HIV was not due to concerns this might discourage testing. Coded information on new diagnoses from the laboratories undertaking confirmatory testing for HIV antibodies has been available since this began.Epidemiological surveillance of AIDS and HIV was initially undertaken by the Department of Health, and since 1989 by the AIDS Epidemiology Group (AEG) based at the University of Otago, Dunedin. The AEGs surveillance has been centered on case reports of AIDS and newly diagnosed HIV infection, supplemented by HIV prevalence studies in sentinel populations. The AEG has also been involved in surveys of behaviours known to drive the spread of HIV and testing patterns.Collectively these three components are now known as Second Generation HIV Surveillance.6 While both diagnoses of AIDS and HIV infection are included in surveillance, since the introduction of effective antiretroviral treatment (ART) in the mid-1990s, the information obtained from AIDS notifications has been less valuable in understanding the epidemic of HIV infection than previously.The findings from the AEGs surveillance have been regularly reported in the newsletter AIDS New Zealand, but as there has been no recent published review of the New Zealand epidemic, we have taken opportunity of the 30th anniversary of HIV testing in New Zealand to review the current epidemiology.The aims of this article are therefore to (a) summarise key findings of the current epidemiology based on reports of diagnosed AIDS and HIV in New Zealand, (b) discuss how these, and findings from other sources, inform HIV care and prevention needs among particular groups in New Zealand, and (c) consider important areas for future epidemiological surveillance.MethodsAn individual with HIV infection is defined as having AIDS when he or she first develops one of a number of specific conditions uncommon in people with normal immunity. Clinicians diagnosing AIDS are required to make an unnamed coded notification to the Medical Officer of Health, which are then forwarded to the AEG; the code is based on the individuals initials, gender and date of birth. The information required includes key demographic characteristics, the AIDS-defining condition and likely means of infection.Since antibody testing for HIV infection first became available in New Zealand in 1985, the number of people newly diagnosed with HIV on the basis of a confirmatory Western Blot (WB) antibody test has been available from the two laboratories undertaking this testing, Auckland City Hospital Virology Laboratory and the Institute of Environmental Science and Research Limited, Porirua. These laboratories have provided the age, sex and likely means of infection of these people when it was provided to them.The information was sent initially to the Ministry of Health, and since 1989, to the AEG. As with AIDS, information is only supplied to the AEG by code and never identified by name. Since 1996, the AEG has undertaken enhanced surveillance of HIV, whereby further information is sought from the clinician who requested the test.7 The additional information includes the site of and reason for the test, the infected persons ethnic group, district of usual residence, and likely country of infection. The categorisation of the regions is based on the areas covered by the Regional Health Authorities that existed when surveillance of HIV was intensified in the 1990s, with the population of the Northern Region being mainly made up of people living in Auckland. From the beginning of 2002, the laboratories performing HIV viral load (VL) testing have provided the codes derived in the same ways as for AIDS notifications and HIV information of people having their first VL test in their laboratory. If it appears through linking of the code to the AEGs HIV database that a person having a VL test had not had a positive HIV antibody test in New Zealand, information is sought from the clinician who requested the VL test. This was established initially to gain information on people being cared for in New Zealand with HIV infections diagnosed overseas, without having had an antibody test in this country. However, VL testing has increasingly been used to confirm new HIV infections, so is now an important source of people being first diagnosed here.Since 2005, information on the initial CD4 cell count has been requested on people newly diagnosed with HIV infection in New Zealand;8 initially, this was only among those whose diagnosis was confirmed through WB testing, but subsequently through VL testing, if the infection was first diagnosed in New Zealand. The initial CD4 count gives an indication of the stage of the disease at diagnosis, and when less than 350 cells per cubic milliliter, it is considered a late diagnosis.To compare the recent epidemic among men who have sex with men (MSM) in New Zealand with that of other high-income countries, the annual diagnosis rate of HIV infection of MSM in selected countries were compared. These diagnosis rates were derived annually for each country from 2004-2013 using the number of diagnoses among MSM as the denominator and the number of men aged 15-64 as the numerator. Details of the method are reported in the Appendix.Information has been collected since 1998 from paediatricians, via the New Zealand Paediatric Surveillance Unit, on babies born to women with HIV diagnoses at the time of delivery.9We present and describe key findings on the reports of AIDS and diagnosed HIV infection. As this is a surveillance report, statistical testing is not undertaken. Where appropriate we have combined data reported over the five-year period 2010-2014 to give an indication of the current pattern of diagnoses.ResultsAIDSOverall, there have been 1,153 people notified with AIDS to the end of 2014 (Table 1). Just over two-thirds (67.2%) of notifications were among gay, bisexual and other MSM infected through homosexual contact, with men and women infected through heterosexual contact the second largest group (20.7%). The age at diagnosis ranged from less than one to 78 years of age, with a median of 39 years; although for most of these people, infection would have occurred at a younger age, as the median time from HIV infection to the development of AIDS is around ten years in untreated young adults, and shorter in older people.10Table 1: Gender, likely means of infection, age (at diagnosis), and ethnicity of people diagnosed with AIDS in 2010-2014 and <2010 and in total. 2010-2014 <2010 Total No. % No. % No. % Total 105 100.0 1,048 100.0 1,153 100.0 Gender Male 85 81.0 932 88.9 1,017 88.2 Female 20 19.0 113 10.8 133 11.5 Transgender 0 0.0 3 0.3 3 0.3 Likely means of infection Homosexual contact (MSM) 57 54.3 718 68.5 775 67.2 Homosexual (MSM) or IDU 1 1.0 14 1.3 15 1.3 Heterosexual contact 33 31.4 206 19.7 239 20.7 Injecting drug use (IDU) 1 1.0 24 2.3 25 2.2 Transfusion or blood product recipient 0 0.0 21 2.0 21 1.8 Mother to child transmission 0 0.0 18 1.7 18 1.6 Other 0 0.0 5 0.5 5 0.4 Unknown 13 12.3 42 4.0 55 4.8 Age at diagnosis (years) <5 0 0.0 12 1.1 12 1.0 5-14 0 0.0 10 1.0 10 0.9 15-19 0 0.0 4 0.4 4 0.3 20-29 9 8.6 159 15.2 168 14.6 30-39 21 20.0 399 38.1 420 36.4 40-49 41 39.0 298 28.4 339 29.4 50-59 20 19.1 123 11.7 143 12.4 > 60 14 13.3 40 3.8 54 4.7 Unknown 0 0.0 3 0.3 3 0.3 Ethnicity European 54 51.4 722 68.9 776 67.3 M\u0101ori 22 20.9 116 11.1 138 12.0 Pacific Islander 5 4.8 35 3.3 40 3.5 African 5 4.8 77 7.3 82 7.0 Asian 13 12.3 64 6.1 77 6.7 Other 5 4.8 27 2.8 32 2.8 Unknown 1 1.0 7 0.7 8 0.7 The annual number of diagnoses of AIDS, and deaths of people notified with AIDS, are shown in Figure 1. AIDS diagnoses peaked in 1989 and 1990 with 71 cases, and deaths in 1992 with 66. The dramatic drop in the number of diagnoses in the mid-1990s, which was seen in other high-income countries, is contemporaneous with the introduction of effective antiretroviral therapy (ART).Figure 1: Annual number of diagnoses of AIDS and deaths among people notified with AIDS As well as reducing the number of people with HIV infection progressing to AIDS, treatments available in the mid-1990s resulted in a marked improvement of the survival of people meeting the criteria for AIDS. As an indication of this, of those diagnosed with AIDS in New Zealand in 1990, less that 10% were still alive five years later, while this was the case for over 70% of people diagnosed a decade later in 2000.Ideally, people are diagnosed with HIV infection before developing serious infections that classify them as having AIDS. However in the period 2010-2014, 74.3% (78/105) had been diagnosed with HIV infection at same time or less than 3 months prior to developing AIDS-defining conditions. Among many of those, an earlier HIV diagnosis and prior ART could have avoided progression to AIDS, so earlier HIV diagnosis could be expected to reduce the annual number of AIDS notifications further.HIV infectionInformation obtained from the HIV testing laboratories indicates that 4,168 people have been diagnosed with HIV in New Zealand to the end of 2014 (Table 2). Of these, 3,452 were through positive WB antibody tests, and 716 through having VL tests among people not known by the AEG to have had a prior WB test. While scrutiny of codes have been used to detect duplicate reports, these have not always been provided, especially in the early years of testing, so some duplication cannot be ruled out.Table 2: Likely means of infection of people diagnosed with HIV in 2010-2014, <2010 and total. These figures include people previously diagnosed overseas. 2010-2014 <2010 Total No. % No. % No. % Total 883 100.0 3,286 100.0 4,168 100.0 Homosexual contact (MSM*) 543 61.4 1744 53.0 2,287 54.8 Homosexual contact (MSM*) or IDU 6 0.7 42 1.3 48 1.2 Heterosexual contact 209 23.7 897 27.3 1,106 26.5 Injecting drug use (IDU) 8 1.0 76 2.3 84 2.0 Blood product/transfusion recipient 0 0.0 62 1.9 62 1.5 Mother to child transmission 3 0.3 55 1.7 58 1.4 Other 7 0.8 32 1.0 39 1.0 Unknown/Not stated 107 12.1 378 11.5 484 11.6 *MSM - Men who have sex with menThe annual number of diagnoses by means of infection is shown in Figure 2. It is important to appreciate that for many, the year of diagnosis will not have been the same as when the infection occurred, so is not an indication of true annual incidence.As with AIDS, the majority (56.0%) of those diagnosed with HIV were MSM men infected through homosexual contact a small number of whom were also reported to have injected drugs (Table 2); the proportion rises to 63.4% if limited to those with a reported means of infection.The next largest group were heterosexually infected men and women, 26.4% of all diagnosed, and 30.0% of those with a reported means of infection. Notably few people have been definitely or possibly infected through injecting drug use. In 2010-2014, the proportion of diagnoses among MSM has increased to 70.7% of those with a known means of infection.Figure 2: Number of people diagnosed with HIV in New Zealand, by year of diagnosis and means of infection. These figures include people previously diagnosed overseas. Gay, bisexual and MSMOverall, there have been 2,335 MSM diagnosed with HIV. After an initial rise in the annual number in the late 1980s and early 1990s, the number dropped to a nadir in the late 1990s, with a subsequent rise in the early 2000s (Figure 2). While there was a steady increase in the years 2001 to 2005, since then the annual number has fluctuated. The highest ever annual number of MSM was diagnosed in 2014, and could indicate an upward trend in incidence, but it is too soon to conclude this. The overall rise since the early 2000s has been greatest among those infected in New Zealand rather than overseas (Figure 3).Figure 3: Place of infection of MSM first diagnosed with HIV in New Zealand by year of diagnosis, 1996-2014. These figures exclude people previously diagnosed overseas Although the median age for HIV diagnosis among MSM was 37 years, the range is wide, with the youngest being 16 and oldest, 78 years. As well as appreciating that these are the ages at diagnosis not infection, it needs to be kept in mind that this will not reflect the current age profile of MSM living with HIV, which will be older in view of the success of current treatments.The ethnic profile of MSM diagnosed in the five-years 2010-2014 (Table 3) is broadly similar to that of the male population aged 15-64 in the 2013 census. The higher proportion of an \u201cother\u201d ethnicity among HIV diagnoses is a reflection of people from overseas diagnosed here. The increase in recent years in the proportion of Asian people likely reflects the changing ethnic make-up of Auckland, where over 50% of newly diagnosed MSM and the HIV epidemic in MSM is concentrated (Table 3).Table 3: Characteristics of men who have had sex with men (MSM) diagnosed with HIV in 2010-2014, <2010 and total. These figures include people previously diagnosed overseas. 2010-2014 <2010 Total No. % No. % No. % Total 549 100.0 1,786 100.0 2,335 100.0 Age at diagnosis 15-19 11 2.0 34 1.9 45 2.0 20-29 142 25.9 468 26.2 610 26.1 30-39 151 27.5 652 36.5 803 34.4 40-49 148 27.0 382 21.4 530 23.0 50-59 64 11.7 155 8.7 219 9.1 60 or more 33 5.9 45 2.5 78 3.3 Unknown 0 0.0 50 2.8 50 2.1 Likely place of infection* New Zealand 353 64.3 655 58.2 1,008 60.2 Overseas 177 32.2 414 36.8 591 35.3 Unknown 19 3.5 57 5.0 76 4.5 Ethnicity* European 348 63.4 838 74.3 1,186 70.7 M\u0101ori 50 9.0 121 10.7 171 10.2 Pacific 19 3.5 36 3.2 55 3.3 Asian 84 15.3 77 6.8 161 9.6 African 0 0.0 7 0.6 7 0.4 Other 46 8.4 45 4.0 91 5.4 Unknown 2 0.4 4 0.4 6 0.4 Usual residence* New Zealand 516 94.0 1,030 91.3 1,546 92.2 Northern 303 58.7 528 51.3 831 53.7 Midland 41 7.9 137 13.3 178 11.5 Central 104 20.2 177 17.1 281 18.2 Southern 68 13.2 188 18.3 256 16.6 Overseas

Summary

Abstract

Aim

To summarise findings of the epidemiology of AIDS and HIV infection in New Zealand.

Method

Key results from reports of AIDS and diagnosed HIV infection are presented. Where appropriate, data on HIV diagnoses are reported for the period 2010-2014 to indicate the current pattern of diagnoses.

Results

New Zealand has a well-described low prevalence epidemic of HIV infection, mostly concentrated in sub-populations of men who have sex with men (MSM), and heterosexual individuals from sub-Saharan Africa and South-East Asia. The former is largely due to transmission within New Zealand, whereas the latter mostly occurred overseas, although the difference has been less marked in recent years. The number of notified cases of AIDS peaked in the late 1980s, and dropped dramatically in the mid-1990s due to the introduction of effective antiretroviral treatments. Presently, most cases of AIDS are in people with previously undiagnosed HIV infection. In contrast, currently the annual number of diagnoses of HIV infection is higher than in the late 1990s, due to more occurring among MSM. Over the past 30 years, each sub-epidemic has demonstrated a distinct pattern, reflecting different determinants. HIV among people who inject drugs, sex workers, children and the general population has been restricted to very low levels.

Conclusion

Control of HIV in New Zealand is favourable compared to many countries, however challenges remain, especially in prevention among MSM, and more timely diagnosis for all, especially those heterosexually infected. National monitoring of the clinical outcomes of people diagnosed with HIV would provide an indication of the provision of effective care and allow international benchmarking.

Author Information

- Nigel Dickson, Department of Preventive and Social Medicine, University of Otago, Dunedin; Bible Lee, Preventive and Social Medicine, University of Otago, Dunedin; Timothy Foster, Department of Preventive and Social Medicine, University of Otago, Dunedin; Peter Saxton, Social and Community Health, University of Auckland, Auckland. -

Acknowledgements

Correspondence

Nigel Dickson, Department of Preventive and Social Medicine, University of Otago, Dunedin

Correspondence Email

nigel.dickson@otago.ac.nz

Competing Interests

'- - Centers for Disease Control. Kaposis sarcoma and pneumocystis pneumonia among homosexual men - New York City and California. MMWR 1981;30:305-8 Romeril KR. Acute HTLV III infection (letter). NZ Med J 1985;98:401 Gallo RC, Montagnier L. AIDS in 1988. Scientific American 1988;259:40-48 Carlson RV, Skegg DC, Paul C, Spears GF. Occurrence of AIDS in New Zealand: the first seven years. MRC AIDS Epidemiology Group. NZ Med J 1991;101:131-134 World Health Organization. Consolidated strategic information guidelines for HIV in the health sector. Switzerland: World health Organization. Available from: http://apps.who.int/iris/bitstream/10665/164716/1/9789241508759_eng.pd f?ua=1&ua=1 World Health Organization and Joint United Nations Programme on HIV/AIDS. Guidelines for Second Generation HIV Surveillance. World Health Organization and Joint United Nations Programme on HIV/AIDS, Geneva 2000. Paul C, Wilson M, Dickson N, Sharples K, Skegg DC. Enhanced surveillance of HIV infections in New Zealand, 1996-1998. NZ Med J 2000;113:390-394 Dickson NP, McAllister S, Sharples K, Paul, C. Late presentation of HIV infection among adults in New Zealand: 2005-2010. HIV Med 2012;13:182-189 Dickson N, Paul C, Wilkinson L, Voss L, Rowley S. Estimates of HIV prevalence among pregnant women in New Zealand. NZ Public Health Reports 2002;9:17-19 Bacchetti P, Moss AR. Incubation period of AIDS in San Francisco. Nature 1989;338:251-­3 Ministry of Health. Country Progress Report New Zealand (HIV/AIDS) 2014. Wellington, New Zealand. Available from: http://www.health.govt.nz/publication/country-progress-­report-­new-­zealand-­hiv-­aids-­2014 Curtis H, Yin Z, Clay K, Brown AE, Delpech VC, Ong E. People with diagnosed HIV infection not attending for specialist clinical care: UK national review. BMC Infect Dis 2015;15:315 Saxton PJ, Dickson NP, Griffiths R, Hughes AJ, Rowden J. Actual and undiagnosed HIV prevalence in a community sample of men who have sex with men in Auckland, New Zealand. BMC Public Health 2012;12:92 Saxton P, Dickson NP, McAllister S, Sharples K, Hughes A. Increase in HIV diagnoses among homosexual men in New Zealand from a stable low period. Sex Health 2011;8:311-318 Saxton P, Dickson N, Hughes A. Location-based HIV behavioural surveillance among MSM in Auckland, New Zealand 2002-2011: Condom use stable and more HIV testing. Sex Transm Infect 2014;90:133-138 Psutka R, Dickson N, Azariah S, Couglan E, Kennedy J, Morgan J, Perkins N. Enhanced surveillance of infectious syphilis in New Zealand Sexual Health Clinics. International Journal of STD & AIDS, 2013;24:791-798 Henderson C, Brunton C, Lauzon C. Final Report of the National Needle Exchange Blood-borne Virus Seroprevalence Survey [BBVNEX2009] to the New Zealand Ministry of Health. 2011. Unpublished report to the Ministry of Health Gardner EM, McLees MP. Steiner JF, del Rio C, & Burman WJ. The spectrum of engagement in HIV care and its relevance to test-and-treat strategies for prevention of HIV infection. Clinical infectious diseases, 2011;52:793-800 Raymond A, Hill A, Pozniak A. Large disparities in HIV treatment cascades between eight European and high-income countries-analysis of break points. Conference presentation at HIV Drug Therapy Glasgow Congress, 2014. Journal of the International AIDS Society 2014, 17(Suppl 3):19507 Cleveland WS. LOWESS: A program for smoothing scatterplots by robust locally weighted regression. Am Stat 1981;35:54 R Core Team. R: A language and environment for statistical computing. R Core Team. Vienna, Austria 2012.- -

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for the PDF of this article

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