Tracking AIDS

He Kitenga, 2005

HIV/AIDS is one of the most difficult infectious diseases to keep track of. Because most of those who contract the condition do so via deeply private activities such as sexual intercourse or drug use, it lives a rather subterranean existence. Trying to track its destructive path, then, is not the easiest of tasks.He Kitenga

For the past 15 years Dr Nigel Dickson (Department of Preventive and Social Medicine) has been leading the charge in this area. He directs New Zealand’s AIDS Epidemiology Group – a body established in 1989 by Professors David Skegg and Charlotte Paul.

“Our role here in surveillance,” says Dickson, “is to collect the data, analyse it, make sense of it, and then feed it back to those who are in the position to plan action – like the Ministry of Health and the organisations involved in health promotion such as the AIDS Foundation.”

It’s the consistency and the longevity of the surveillance that merits mention. “Sometimes it’s not the fact that it’s new research,” says Dickson, “but the fact that you’ve been doing the same thing in a consistent manner for 15 years.”

Contracted by the Ministry of Health to undertake epidemiological surveillance of HIV/AIDS, the group gathers its statistics from various sources. Because AIDS is a notifiable condition, most of the data is automatically passed on, but further statistics can be gleaned from reports of new diagnoses of HIV and prevalence surveys. The latter gauge how common HIV is in particular groups, such as drug users and those who attend sexual health clinics. Following guidelines set out by the World Health Organisation, the group initiates “unlinked anonymous surveys” in which they effectively piggy-back on blood that has been drawn for other purposes (e.g. to be tested for syphilis or Hepatitis B). After the primary test is done, a little bit of blood is removed and “anonymised” (so it can be linked only to non-identifying information such as age, sex, sexual behaviour) before being tested for HIV.

As well as maintaining ongoing surveillance of the HIV/AIDS epidemic, these statistics help bolster other lines of enquiry and yield many fruitful collaborative projects.

One area currently under debate is whether there should be widespread testing for HIV among pregnant women to eradicate the risk of undiagnosed mothers unwittingly infecting their babies. Then there’s the work that Dickson and his colleagues have done with both the Ministry of Health on developing a national questionnaire on sexual and reproductive behaviour, and with the AIDS Foundation on behaviour surveys among men who have sex with men.

Their most recent collaboration is with Nga Pae o te Maramatanga, the National Institute of Research Excellence for Mäori Development and Advancement at the University of Auckland – a partnership that forms the New Zealand arm of an international study on how best to develop resiliency to HIV, STDs and blood-borne viral infections among indigenous people.

So what do all these statistics tell us about where New Zealand sits internationally with its HIV/AIDS management?

“The control of the epidemic has been as good here as anywhere,” says Dickson. “Although there has been a recent increase in the number of diagnoses of HIV among gay men, the rate is still less than in Australia, which is probably the most comparable country.”