Population estimates and the war against HIV/Aids
- Paul Berkowitz
- 09 Sep 2011 07:49 (South Africa)
The latest mid-year population estimate from StatsSA points to a bright light at the end of the HIV/Aids tunnel for the country. PAUL BERKOWITZ takes a closer look at the numbers and their implications.
Numbers are funny things. Ask 10 different South Africans how many people live here, and you’ll receive 10 different answers. One of them might resemble the official mid-year population estimate which puts the figure at 50.6 million people, give or take. Someone better tell Eskom that its estimate of 49 million is so late-2008. On the other end of the range of estimates is economist Mike Schussler, who claims we may have as many as 60 million people in South Africa.
South Africa’s demographic narrative is a highly contested one. The story of South Africa’s HIV problem as told by the Treatment Action Campaign is vastly different to the one told by Rian Malan. For every Zimbabwean the department of home affairs claims is living in the country, someone at a braai somewhere will claim that there are two Zimbabweans. Or four.
Until the results of this year’s upcoming census are audited and finalised, we’ll have to keep relying on the official population projections. The trends identified by the official numbers make for some interesting reading.
Firstly, the prevalence of HIV (percentage of total population which is HIV-positive) has increased from 9.4% in 2001 to 10.6% in 2011. In sheer numbers, HIV-positive people have increased from 4.2 million to 5.4 million. Almost one in nine South Africans is HIV-positive, but this rises to one in six of people aged 15 to 49 years (16.6%) and almost one in five of all women between 15 and 49 years (19.4%).
That’s the bad news. The good news is that the incidence of HIV (percentage of HIV-negative people who become infected in any one year) peaked in 2006 at 2.1% and has fallen to 1.4% in 2011. This is the lowest rate of incidence in more than a decade. The slowdown in the rate of new cases recorded is largely due to interventions to prevent mother-to-child transmission, because the prevalence rate among women of child-bearing age continues to climb.
The assumptions underpinning the peaking and subsequent decline in the HIV incidence rate (driven mainly by the increased rollout of ARVs) also feed through into the modelling of life expectancy at birth and the crude death rate. Life expectancy is a highly politicised number. It’s one of the three primary statistics used to calculate the official UN Human Development Index for a country. South Africa’s HDI had fallen for much of the late 1990s and early 2000s. The latest data claim that life expectancy reached a low of 51.8 years in 2005 and has since risen, reaching 57.1 years in 2011 – its best level in a decade. Similarly, the crude death rate is recorded as having peaked at 14.4 deaths/1,000 people in 2005, subsequently declining to 11.7. Once again this is the best level in a decade.
These figures, if true, represent a major victory for the department of health. They point to a causal link between its actions on the HIV epidemic and the positive demographic outcomes.
Of course, these numbers produced by the official model are highly contested. They bear little resemblance to the figures given by the UN. The model itself is underpinned by the 2001 Census, where a very large undercount of the population dealt a severe blow to the credibility of any derived data. The model is, however, updated and monitored by the Actuarial Society of South Africa. You’re safer trusting their numbers than all the amateur News24 and TimesLIVE demographers put together, with their back-of-the-braai-pack calculations about how life expectancy will fall to 35 years under another decade of ANC rule.
Even if the model is accurate (and we might only be able to compare it to the Census 2011 numbers in two years’ time) we’ve only won one battle in the war. The rate of new infections may have peaked, but the ranks of the HIV-positive still swell by about 120,000 people a year – the share of the public health pie going to ARV provision isn’t likely to shrink significantly over the medium-term. The broader social costs of HIV are also still with us, including the issues of child-headed households and the ongoing deaths of the economically productive cohorts of society.
As a country, we need to absorb the future implications of these trends quickly so that those areas of government responsible for public health and social development can adapt their programmes to deal with remaining challenges. We have extended the quantity of life available to HIV/Aids sufferers over the last six years. We now need to work much harder to improve the quality of that life. DM
- 2011 Mid-Year Population Estimates, StatsSA.