Before we begin I would like to say a little about the Medical Research Council (MRC)(slide). We are a Statutory Council established by Act of Parliament and therefore accountable to you and the people of South Africa (slide). We therefore take very seriously our responsibility of providing you with accurate and reliable information on the health research and health matters in general. These slides show the 48 research units of the MRC that are spread across the country.

1. The Context of the HIV and AIDS Epidemic

From its earliest beginning with Slim Disease in East Africa, the HIV and AIDS epidemic has always been associated with poverty. This is true not just for developing countries but also wealthy countries such as the USA where HIV and AIDS inordinately affects the poor and marginalised in American society such as African Americans and users of intravenous illicit drugs. Even in South Africa workplace surveys show a similar trend with rates of HIV seroprevalence falling the higher in the company one looks.

South Africa, though an upper middle income country, displays vast disparities in income distribution (slide), much of this predicated on race due to the country’s history of apartheid and colonialism that culminated in the Bantustans that you see on this slide . Thus overall infant mortality in South Africa in 2004 was 55 per 1000 live births; but in more affluent segments of the population approaches ‘first world’ levels of less than 10 per 1000 as can be seen from this slide. Through increased provision of primary health care and attendants at birth, inroads should be made into this figure but the HIV epidemic reduces the effect of these interventions.

Several South African studies have shown an association between HIV seroprevalence and work migrancy; or living in poor and meagre shelter. This is an old slide from 1999 but shows that many South Africans still live in inadequate shelter, with poor sanitation and no piped potable water in their homes; with marked disparities in social circumstances between different regions; and between urban and rural dwellers.

2. What is the Natural History of HIV and AIDS?

Before one can investigate the socioeconomic impact of a disease, it is necessary to understand its natural history. This is the first stumbling block - we simply do not understand the natural history of HIV and AIDS.

As this slide shows, the epidemic has progressed quickly over the past 15 years – though not as quickly as experts in the late 1980s and early 1990s predicted. The National Department of Health has tracked the progress of the epidemic through anonymous unlinked serological surveillance of women attending Antenatal Clinics. The figures are then extrapolated to the general population which introduces a degree of error; but the data is particularly good for plotting trends in HIV seroprevalence as the same methodology is used year after year.

The epidemic was probably fuelled by migrant labour conditions and the social dislocation that this causes. A similar phenomenon occurred when the diamond mines were opened in Kimberley in the 1870s – accompanied then by increasing rates of sexually transmitted disease (STD) that had been rare in Southern Africa hitherto as Sidney Kark described in 1949. It seems likely that concomitant STD increase transmission of HIV during sexual intercourse many fold.

Other potentiating factors for HIV infection and the descent into AIDS are thought to include poverty and malnutrition which may in themselves weaken the immune system, poor housing conditions, poor saniation and lack of clean drinking water.

Poor levels of education are also described as risk factors for HIV and AIDS; as are disordered gender and power relations – another field in which the MRC is doing research.

Inroads have been into the HIV epidemic through improved detection and treatment of STDs, particularly in Antenatal Clinics as this slide shows.

We use the term HIV and AIDS to clarify the fact that once infected with HIIV and individual does not immediately progress to AIDS. In affluent countries, that descent into immune destruction can take between 7 and 15 years. In poor African countries it typically takes 2 – 7 years. This different time course will obviously impact affect the degree of socioeconomic impact caused by the disease.

3. The Demographic Impact of HIV and AIDS

AIDS is a particularly tragic condition as it afflicts principally the young – though its effects are felt by all sectors of society. In Africa HIV is spread predominantly through heterosexual contact; and as can be seen from the graph the young sexually active population are inordinately affected by the disease.

Evidence from the Antenatal Clinic Survey (ANC Survey) suggests that the demographic impact of the disease may be changing. Formerly the highest incidence rates seemed to be occurring amongst those aged 15 – 25; now this seems to have shifted to those aged 25 – 35.

Much of the socioeconomic impact of HIV and AIDS arises due to the death of South Africans at a young age, between 25 and 45, an age when they are still economically and socially active as can be seen from these three slides from our Burden of Disease Research Unit at the MRC. To quantify this mortality is difficult as vital registration or certification of death by doctors does not provide an accurate figure for AIDS-related deaths. This is partly due to the reluctance of doctors to write HIV or AIDS on the death certificate. Thus in 1996 the cause of death data estimated 2% of deaths were due to AIDS, and in 2001 2.8% clearly an underestimate. Demographic modelling is therefore used such as the Actuarial Society of South Africa 2000 model (ASSA2000), which estimated AIDS-related deaths in 2000 to have been approximately 165 000.

Demographic modelling is often used to gain a clearer picture of AIDS mortality and its impact on the population; but this is sometimes not straightforward as the recent experience with the (ASSA 2000) demonstrates. This ‘AIDS and Demographic model’ was used for projecting the impact of HIV/AIDS on the South African population. We used its projections when we wrote the Comprehensive Plan in order to attempt to estimate the number of people who would become HIV positive over the coming years; and the proportion who would fall AIDS sick. Unfortunately the model overestimated by 25%; with the new ASSA2002 model, predicting that some five million South Africans (and not seven million as predicted by ASSA2000) were HIV positive in 2004. The Actuarial Society stated that ‘the lower estimates are mainly due to improvements to the model to incorporate more up-to-date evidence that the relationship between antenatal prevalence and general population prevalence in South Africa is not the same as that observed in other African countries, where fertility is much higher than it is in South Africa. However, it is also due in part to the fact that the new model allows for interventions that have been in place for some years (such as increasing use of condoms and improved treatment of sexually transmitted infection (STDs))’.

The Actuarial Society goes on to state that ‘Apart from improved estimates of the extent of the epidemic, the main development in ASSA2002 is to incorporate the impact of interventions. Five interventions have been modelled: information and education campaigns, improved treatment of sexually transmitted diseases, voluntary counselling and testing, mother to child transmission prevention and antiretroviral treatment. This makes the model much more relevant at a time when both the public and private sectors are rolling out various’.

The ASSA2002 assumes that 10% of those who are positive are AIDS sick requiring treatment including antiretrovirals. From this methodology they estimate that approximately 500 000 South Africans in 2004 were AIDS sick; whereas ASSA2000 predicted 700 000.

The ASSA2002 model also revises the life expectancy at birth figure – an important figure when attempting to predict socioeconomic impact of a disease. The new figure is 7 years higher than predicted with the ASSA2000. ASSA2002 predicts that the population size is affected by HIV/AIDS and the annual growth rate is projected to slow down but remain positive. It fell to 0,8% in 2004 and is projected to drop to 0,4% in the years beyond 2011.

4. Prevention

1. Comprehensive Prevention, Treatment and Care for HIV and AIDS

What about treatment – what effect does have on the socioeconomic impact of HIV and AIDS? Again the answer is we do not know. There are several factors to consider.

a. Survival.

Little is known about the length of survival of patients on antiretroviral therapy in resource poor settings. Data from ACTG studies in the USA, using regimens similar to those we use in South Africa suggest that median survival once started on ARVs is likely to be of the order of several years but this is very tentative.

b. Return to work.

The theory often quoted is that the socioeconomic impact of HIV and AIDS will be mitigated by treatment as patients will survive longer and return to work. There is no good, rigorous evidence to support this assertion. The complexities of treatment regimens, side effects of therapy, psychological responses to the disease and the nature of hard physical labour make it unlikely that, in the South African context, this will be a major factor. More workbased research is needed and the MRC is planning such studies.

c. Reduction of hospital burden.

Several studies have been performed to attempt to quantify the costs of HIV and AIDS in terms of the burden on hospital beds – which in many instances have up to 50% of space filled by patients with AIDS-related illnesses. No nationally representative studies have been performed however.

It should be remembered that however, that investment in the Comprehensive Plan should have positive spinoffs in terms of general investment in the National Health System to the benefit of a wider range of patients.

d. Reduction in numbers of children orphaned as a result of HIV and AIDS

Some investigators have attempted to quantify the numbers of children orphaned as a result of deaths of their parents from AIDS.

Also significant are the numbers of households where grandparents, whose own children have died of AIDS bear the burden of looking after the orphaned grandchildren. The MRC is also undertaking research in this field.

Is the expenditure of R12 billion over 5 years in the Comprehensive Plan, in addition to the billions already being spent annually on HIV and AIDS justified? When we presented the Operational Plan to Cabinet in November 2003 the case we made was not based on economic considerations because the data was not there to support such an economic argument.

The continuing implementation of the Comprehensive Plan should improve our understanding of the socioeconomic impact of HIV and AIDS as, to date, well over

100 000 people have been screened and their HIV status established. If these people continue in care or followup, the natural history of those who are positive will be better understood.

The importance of nutrition in mitigating the impact of HIV and AIDS cannot ne understated. The Tanzanian/Harvard University clinical trial by Fawzi et al published recently in the New England Journal of Medicine is a casein point. This blinded, randomised controlled clinical trial showed that amongst over 1000 HIV positive women; those assigned to receive daily multivitamin over the subsequent 5 years showed a 30% reduction in death and progression to AIDS compared to those who did not receive multivitamin. This implies that multivitamins can reduce the socioeconomic impact of HIV and AIDS by both reducing the annual death rate, as well as reducing the rate at which patients deteriorate to the point of needing active medical care.

In addition, the widespread use of traditional medicines in AIDS could have direct benefit, if efficacious in reducing mortality; as well as indirect benefit in stimulating the industry of producing and distributing natural medicines.

2. PMTCT

The one area in which treatment does reduce new infections is in PMTCT. Currently nevirapine monotherapy, though not the optimal therapy, can reduce HIV transmission in HIV positive pregnant women from 30% to 15%. The MRC and others are advising government on whether to move to dual or triple therapy, which can reduce transmission rates to below 3%. However in South Africa this is complicated by the widespread practice of mixed breastfeeding which can result in HIV transmission in up to 10% of cases where the mother is positive.

 

3. The economic impact of HIV and AIDS in South Africa

Markus Haacker in an IMF study from 2002 titled ‘The Economic Consequences of HIV/AIDS in South Africa’ states that ‘HIV/AIDS may affect economic growth and income per capita through various channels. Disruption to the production process caused by sickness and death of employees have an adverse impact on productivity, and the decline in the rate of growth of the labour force results in a fall in the rate of growth of GDP. Also HIV/AIDS affects the supply of human capital (relative to the size of the labour force) if the average level of experience in the workforce declines, if HIV prevalence rates differ across segments of the population, and if the quality of education varies from one group to another (Haacker 2002).