Myths on AIDS prevalence
IPN Critical Opinion articles
HIV/AIDS figures in India will have to be drastically slashed as a result of more accurate HIV data. But United Nation’s Programme on AIDS (UNAIDS) continues to stand by its exaggerated guesstimates that distort the magnitude of the Indian epidemic.
In recent years, the joint UNAIDS has been forced to reduce estimates of the number of persons living with an HIV infection (HIV prevalence) in many countries in sub-Saharan Africa and the Caribbean by half or more as a result of more accurate HIV data but as of 2007, HIV prevalence estimates in many Asian countries remain grossly overestimated — with India officially top of the world league.
There is a widespread misconception among vocal AIDS activists that all official HIV prevalence estimates are grossly underestimated — most news reports carry the inevitable: “However, most AIDS experts believe that the actual HIV numbers are much higher than the official estimate.”
In fact, the official numbers may be grossly overestimated. The primary method for estimating HIV prevalence in a country like India is to use serological survey data, testing blood collected from selected samples for HIV antibodies. Major problems with this method are the limited number of “sero-survey” studies that might be representative of specific populations or subgroups, and the wide variability in estimates of the size of groups with risky HIV behaviour.
HIV sentinel surveillance (HSS) is the routine collection of blood samples from specific “sentinel” populations to monitor the trend of HIV infection rates in these sentinel populations. Although HSS systems were not designed to provide data for making HIV prevalence estimates, they have been used in India for this purpose primarily because there were no other HIV data available.
However, HSS data are usually heavily biased by inclusion of mostly urban “sentinel sites” where the highest HIV prevalence might be found: this bias is significantly present in the Indian data. In late 2006, Lalit Dandona and colleagues released results of a well-designed population-based (randomly selected cluster samples of urban and rural populations) HIV sero-survey in the high HIV-prevalence district of Guntur in Andhra Pradesh.
Their findings indicate that the official national Indian estimation methods using data obtained from sentinel antenatal clinics and the unique Indian assumptions regarding other sexually-transmitted disease ratios had led to gross overestimation.
Based on their study and extrapolation to other states with high HIV prevalence, they came up with a national estimate of three to 3.5 million. However, if Dandona’s correction of almost 60% lower is applied to the total national estimate of five to six million, the revised national HIV prevalence estimate may be just a bit over two million.
UNAIDS will most likely try to argue that population-based type surveys in Asian populations may underestimate HIV prevalence, and this may in fact be the case. However, all of the population-based HIV studies carried out in 2006 in India should cut by at least half and possibly more the official estimates by UNAIDS or the Indian National AIDS Control Organisation (NACO).
Projection of future HIV prevalence is even more uncertain than estimation of current HIV prevalence. In the newly released 2006 revision of the estimates and projections of population by the UN Population division, projected HIV prevalence in 2025 in India was reduced to less than five million — a projected 20% decrease from the current UNAIDS estimate of almost six million.
This is in stark contrast to the UNPOP’s HIV projection for India in their 2002 revision that forecast a marked future increase in HIV prevalence. The most unrealistic projection for India came from the US National Intelligence Council in 2002 when they projected that HIV prevalence might be close to 20 million by 2010. Not to be outdone, the UNAIDS Independent Commission in Asia has just said infections could more than double in Asia in the next five years.
Unrealistically high HIV-prevalence estimates and projections in many Asian countries are being exposed as, at best, naive efforts of well-meaning AIDS programme advocates and, at worst, the work of AIDS “experts” who ignore or deny the more credible lower estimates and projections, to support their own political, social, economic, or personal agendas. But for such a serious infection as HIV, a prevalence of two to three million still represents a huge public health problem for India.
Inflating HIV numbers may in the short term help UNAIDS to garner more support for AIDS programmes, but can also result in an eventual backlash and withdrawal of public and policymaker support when such inflated numbers cannot be defended. Right now NACO is proposing a five-fold increase in funding but this increase is based on grossly inflated HIV estimates: only with the most accurate HIV estimates and projections can limited resources be allocated to the right people in the right places.