Re: UN Cries Wolf About AIDS

[Guest guest]

Chin's Criticism of UNAIDS is grossly inaccurate.

Re: /message/7568

Many of the claims in Chin's account of the HIV pandemic are

unfair and inaccurate. Estimation methods used by UNAIDS are guided

by a reference group providing independent scientific advice.

Contrary to Chin's statement, these methods have regularly been

published in peer reviewed journals and are available for scientific

appraisal and criticism.

Sentinel HIV surveillance, originally recommended by Chin, has many

well recognized biases when used to try and estimate the prevalence

in a country's population. In particular, antenatal clinic data tend

to be from urban populations. As these biases have been identified,

estimates of the epidemic have been adjusted [1].

In an ongoing effort to improve the accuracy of national estimates, UNAIDS has

been recommending since 2000 that countries expand their data sources to include

more information on rural populations and on high risk populations. Adjustments

in national prevalence have been made, bringing the total number of persons

infected down by about 20%.

In his reference to India, Chin's claim that UNAIDS estimated 5.7

million people living with HIV in 2005 and now the Indian National

AIDS Control Organization (NACO) lowered the number to 2.5 million

neglects to mention that UNAIDS has been working with India since

1998 and that all the estimates have been the results of work

coordinated by NACO with UNAIDS and WHO support.

His claim that Kenya's HIV estimate was reduced from 2.3 million to

1.1 million in 2003 is based on the result of a population based

survey AND the fact that the HIV epidemic had begun to decline. This

decline is observed in consistently sampled sites, so is not a result

of more representative data [2]. Similarly for Haiti the reduced

estimate is due to both adjustments to past estimates and the fact

that the HIV epidemic is declining.

Based on the inclusion of the results of population based surveys

adjusted for non-response, HIV estimates for most countries in sub-

Saharan Africa have already been adjusted. These comparisons and the

relevant adjustments are described on the UNAIDS website. [3]

In summary, the characterization of UNAIDS as an advocacy

organisation which ignores evidence does not tally with the

transparent process used to provide estimates and projections, which

has been cited as a model of good practice [4]. UNAIDS and its

partners will continue to assist countries to obtain a more accurate

understanding of their epidemic. Only with this knowledge, can the

national response be effective to reduce new infections and extend

the lives of those with AIDS.

[1] N, Grassly NC, Garnett GP, Stanecki KA & Ghys PD.

Estimating the global burden of HIV/AIDS: How much do we really know

about the HIV pandemic? Lancet 2004; 363: 2180-2185.

[2] Hallett TB Aberle-Grasse J Bello G Boulos L-M Cayemittes MPA

Cheluget B Chipeta J Dorrington R Dube S Ekra AK -Calleja JM

Garnett GP Greby S Gregson S Grove JT Hader S Hanson J Hladik W

Ismail S Kassim W Kirungi W Kouassi L Mahomva A Marum L Maurice C

Nolan N Rehle T Stover J N. Declines in HIV prevalence can be

associated with changing sexual behaviour in Uganda, urban Kenya,

Zimbabwe and urban Haiti Sexually Transmitted Infections 2006 82

(Suppl 1); i1-i8.

[3]http://www.unaids.org/en/MediaCentre/PressMaterials/FeatureStory/20070

705_population_based_surveys.asp. Additional adjustments of a lesser

magnitude are expected in 2007

[4] Murray CJ Towards good practice for health statistics: lessons

from the Millennium Development Goal health indicators. Lancet 2007,

369: 862-873.

Professor Geoff Garnett,

Imperial College London.

Chair of The UNAIDS Reference Group on Estimates, Models and Projections.

Best wishes Geoff

e-mail: <g.garnett@...>