South Africa: The Complex Story of HIV Prevalence
By Thabile Sokupa
Recent figures released by the Department of Health have been trumpeted by government as evidence that their prevention efforts are succeeding. However, communities in South Africa still face an unprecedented crisis as the spread of HIV continues increasing in many communities.
The 2008 National Antenatal HIV and Syphilis Prevalence Survey—based on blood samples from 34,000 pregnant women who attended antenatal clinics in 52 health districts—saw stabilising HIV prevalence at 29.3 percent, compared to 29.4 percent in 2007. Prevalence among women aged 15 to 24 declined slightly from 21.7 percent in 2007 to 22.1 percent in 2008, but the infection rate among women in the 30 to 34 age group rose from 39.6 percent in 2007 to 40.4 percent in 2008 (statistics from AIDS Law Project South Africa, 2009). Age was the most important risk factor. Women aged 22 years or older are more likely to be HIV-infected. In this age group, 37.6 percent of African women infected compared to 6.8 percent of white, Asian and coloured women.
Health Minister, Aaron Motsoaledi said that prevalence among women aged 25 years and older has stabilised at high and unacceptable levels. He refused to comment on the success or failure of interventions aimed at combating South Africa's HIV/AIDS epidemic, saying only that the survey was a useful tool for observing trends, providing feedback to health workers, and increasing the commitment to an accelerated response (Chetty & Michel, 2009).
The survey figures revealed wide variations between the country's nine provinces. KwaZulu-Natal recorded the highest prevalence (38.7 percent) and Western Cape the lowest (16.1 percent). At district level, the disparities were even greater—the infection rate ranged from five to 45 percent.
The report recommended finding ways to measure new infections and the success of interventions, and also to triangulate the available data to increase its explanatory power on the dynamics of the epidemic. Dr Rose Mulumba, director of John Snow Research and Training Institute, said that more efforts should be made to generate incidence figures to enable researchers to gauge the prevalence of new infections. "We still have to get the findings for incidence, then we will know for sure whether it's stabilised or not. At the moment we can't tell which are new cases since the report is a combination of both,” she said (AIDS Review, 2009).
Lusanda Mahlalela, from Johns Hopkins South Africa, encouraged all stakeholders to continue with the interventions they had in place while using the report to review those interventions. “It's not for the government alone to continue the fight against the epidemic; we should continue to work together in order to win this battle,” Mahlalela said (AIDS Review, 2009).
But the real story behind increases and decreases in HIV prevalence is far less clear and more complex. According to Professor Hargrove from the Centre of Excellence in Epidemiological Modelling and Analysis (SACEMA), “There's an awful lot of vested interests, but it's sufficiently murky that no one really knows what's going on,” (Dorrington et al, 2009).
In reality, 29 years is not long enough to get to grips with an epidemic that has evolved very differently in different parts of the world: in Europe, North America and Asia it has largely been confined to high-risk groups, like injecting drug users, sex workers and male homosexuals; in Southern Africa, however, it has spread rapidly via heterosexual networks. Dr Brian Williams, another epidemiologist at SACEMA explained that although theories abound, nobody really knows why Southern Africa is worst affected, which makes it very difficult to explain why prevalence is going up or down (Dorrington et al, 2009).
Lack of Reliable and Diverse Data
Part of the problem is not having adequate, reliable surveillance figures. In general, the data had been sketchy and mostly derived from urban populations. The first generation of HIV-prevalence figures has been largely obtained by testing pregnant women at antenatal clinics, but the age groups of the women, and the fact they were clearly having unprotected sex, means that the numbers tended to overestimate HIV infections in the general population.
Where possible, antenatal surveys are now combined with more representative data gathered in household surveys, but UNAIDS noted in its 2007 epidemic update that the high numbers of people who refused to be tested in household surveys, or were absent from home, could lead to underestimations of HIV prevalence.
While prevalence only tells us how many people live with HIV and AIDS, incidence measures the number of new HIV infections that occur during a specific period. Incidence provides the most up-to-date and revealing snapshot of an epidemic, but the technology for determining recent infections is still quite new and prohibitively expensive. In the absence of such surveys, HIV prevalence in people aged 15 to 20 is often used as a proxy, because it is probable that most infections in this age group are recent.
The dynamics of an epidemic can also bring about changes in HIV prevalence. In the early phases, HIV infections have tended to rise steeply and then level off as they reached a saturation point in the population. At a later stage, HIV prevalence might start declining, not necessarily because of widespread behaviour change, but because the number of people dying from AIDS-related illnesses has outpaced the number of new infections. President Jacob Zuma recently warned that the number of deaths in the country would soon outnumber the births. He said that more and more people are dying young, threatening even to outnumber in proportional terms those who die in old age (BuaNews, 2009).
Different Research Needed
In research, it is generally understood that when the mortality rate of those infected reaches a balance with the incidence of new infections, prevalence will plateau. This is the stage that South Africa is currently experiencing. Paradoxically, the impact of a national antiretroviral (ARV) programme that keeps large numbers of HIV-infected people alive for longer might actually increase prevalence, or offset a lower rate of new infections. This could explain why a country with a large ARV programme, like Botswana, has not seen significant declines in HIV prevalence, while Zimbabwe, with its relatively small programme, has. But the real story is probably far more complex and impossible to decipher at present due to the lack of investment in research, monitoring and tracking national AIDS epidemics. “Billions have been spent on virology, but we just haven't done enough basic public health research,” said Williams. “Very few studies have been done trying to understand what's actually going on,” (Dorrington et al, 2009).
Ideally, such a study would need to monitor several thousand people over a period of at least five years testing them regularly for HIV. For Williams, such studies have not been done, and even in-depth evaluations of the impact of specific prevention programmes have been few and far between. Unfortunately, this type of study will take years to develop, and currently monitoring and evaluation tends to be short-term. In the absence of reliable long-term data, Dr Mulumba believes the key to interpreting HIV/AIDS figures is to understand what is going on in our societies more broadly (AIDS Review, 2009). She suggests that looking at social indicators such as the rates of rape and teenage pregnancies, or the numbers of children completing school, could also provide indirect evidence of behaviour change, or lack of it.
Missing Component in ABC Campaign
Behaviour change programmes to prevent HIV transmission have mainly promoted condom use or abstinence, while the 'be faithful', or partner reduction, component of the ABC campaign had been neglected. For example, although abstinence may be a viable option for many young people, for others it may be an unrealistic expectation. Even though prospective studies have shown that condoms reduce risk by about 80 to 90 percent when always used, in real life they are often used incorrectly or inconsistently.
Changing human behaviour is not an overnight process. In the meantime, technologies old and new, from diaphragms to vaccines, are being investigated in the hope that science will succeed where attempts to alter human behaviour have not done as well as anticipated. However, the issue of prevention should not rest solely on the shoulders of government. The prevention of HIV infections has a great deal to do with individual choice.
References
• AIDS Law Project South Africa, 2009. SANAC adopts HIV & AIDS and STI Strategic Plan for South Africa, 2007-2011.
• http://www.alp.org.za/modules.php?op=modload&name=News&file=article&sid=360
• Chetty, D. & Michel, B. 2008. Turning the tide: A strategic response to HIV/AIDS in South African Higher Education: HEAIDS Programme Report 2002-2004. SAUVCA. Pretoria: Sunnyside.
• Dorrington, R., Bradshaw, D., Johnson, L. & Budlender, D. 2009. The demographic impact of HIV/AIDS in South Africa: National indicators for 2009. Cape Town: Centre for Actuarial Society of South Africa.
• Hargrove, J. 2009. HIV pathologies and long term survival. AIDS Review. Vol 7, No 11 pp 1401-1410.
• UNAIDS/ UNICEF/ WHO. 2007. Children on the Brink 2004: A joint report of new orphan estimates and a framework for action. New York: AEI Press.
Recent figures released by the Department of Health have been trumpeted by government as evidence that their prevention efforts are succeeding. However, communities in South Africa still face an unprecedented crisis as the spread of HIV continues increasing in many communities.
The 2008 National Antenatal HIV and Syphilis Prevalence Survey—based on blood samples from 34,000 pregnant women who attended antenatal clinics in 52 health districts—saw stabilising HIV prevalence at 29.3 percent, compared to 29.4 percent in 2007. Prevalence among women aged 15 to 24 declined slightly from 21.7 percent in 2007 to 22.1 percent in 2008, but the infection rate among women in the 30 to 34 age group rose from 39.6 percent in 2007 to 40.4 percent in 2008 (statistics from AIDS Law Project South Africa, 2009). Age was the most important risk factor. Women aged 22 years or older are more likely to be HIV-infected. In this age group, 37.6 percent of African women infected compared to 6.8 percent of white, Asian and coloured women.
Health Minister, Aaron Motsoaledi said that prevalence among women aged 25 years and older has stabilised at high and unacceptable levels. He refused to comment on the success or failure of interventions aimed at combating South Africa's HIV/AIDS epidemic, saying only that the survey was a useful tool for observing trends, providing feedback to health workers, and increasing the commitment to an accelerated response (Chetty & Michel, 2009).
The survey figures revealed wide variations between the country's nine provinces. KwaZulu-Natal recorded the highest prevalence (38.7 percent) and Western Cape the lowest (16.1 percent). At district level, the disparities were even greater—the infection rate ranged from five to 45 percent.
The report recommended finding ways to measure new infections and the success of interventions, and also to triangulate the available data to increase its explanatory power on the dynamics of the epidemic. Dr Rose Mulumba, director of John Snow Research and Training Institute, said that more efforts should be made to generate incidence figures to enable researchers to gauge the prevalence of new infections. "We still have to get the findings for incidence, then we will know for sure whether it's stabilised or not. At the moment we can't tell which are new cases since the report is a combination of both,” she said (AIDS Review, 2009).
Lusanda Mahlalela, from Johns Hopkins South Africa, encouraged all stakeholders to continue with the interventions they had in place while using the report to review those interventions. “It's not for the government alone to continue the fight against the epidemic; we should continue to work together in order to win this battle,” Mahlalela said (AIDS Review, 2009).
But the real story behind increases and decreases in HIV prevalence is far less clear and more complex. According to Professor Hargrove from the Centre of Excellence in Epidemiological Modelling and Analysis (SACEMA), “There's an awful lot of vested interests, but it's sufficiently murky that no one really knows what's going on,” (Dorrington et al, 2009).
In reality, 29 years is not long enough to get to grips with an epidemic that has evolved very differently in different parts of the world: in Europe, North America and Asia it has largely been confined to high-risk groups, like injecting drug users, sex workers and male homosexuals; in Southern Africa, however, it has spread rapidly via heterosexual networks. Dr Brian Williams, another epidemiologist at SACEMA explained that although theories abound, nobody really knows why Southern Africa is worst affected, which makes it very difficult to explain why prevalence is going up or down (Dorrington et al, 2009).
Lack of Reliable and Diverse Data
Part of the problem is not having adequate, reliable surveillance figures. In general, the data had been sketchy and mostly derived from urban populations. The first generation of HIV-prevalence figures has been largely obtained by testing pregnant women at antenatal clinics, but the age groups of the women, and the fact they were clearly having unprotected sex, means that the numbers tended to overestimate HIV infections in the general population.
Where possible, antenatal surveys are now combined with more representative data gathered in household surveys, but UNAIDS noted in its 2007 epidemic update that the high numbers of people who refused to be tested in household surveys, or were absent from home, could lead to underestimations of HIV prevalence.
While prevalence only tells us how many people live with HIV and AIDS, incidence measures the number of new HIV infections that occur during a specific period. Incidence provides the most up-to-date and revealing snapshot of an epidemic, but the technology for determining recent infections is still quite new and prohibitively expensive. In the absence of such surveys, HIV prevalence in people aged 15 to 20 is often used as a proxy, because it is probable that most infections in this age group are recent.
The dynamics of an epidemic can also bring about changes in HIV prevalence. In the early phases, HIV infections have tended to rise steeply and then level off as they reached a saturation point in the population. At a later stage, HIV prevalence might start declining, not necessarily because of widespread behaviour change, but because the number of people dying from AIDS-related illnesses has outpaced the number of new infections. President Jacob Zuma recently warned that the number of deaths in the country would soon outnumber the births. He said that more and more people are dying young, threatening even to outnumber in proportional terms those who die in old age (BuaNews, 2009).
Different Research Needed
In research, it is generally understood that when the mortality rate of those infected reaches a balance with the incidence of new infections, prevalence will plateau. This is the stage that South Africa is currently experiencing. Paradoxically, the impact of a national antiretroviral (ARV) programme that keeps large numbers of HIV-infected people alive for longer might actually increase prevalence, or offset a lower rate of new infections. This could explain why a country with a large ARV programme, like Botswana, has not seen significant declines in HIV prevalence, while Zimbabwe, with its relatively small programme, has. But the real story is probably far more complex and impossible to decipher at present due to the lack of investment in research, monitoring and tracking national AIDS epidemics. “Billions have been spent on virology, but we just haven't done enough basic public health research,” said Williams. “Very few studies have been done trying to understand what's actually going on,” (Dorrington et al, 2009).
Ideally, such a study would need to monitor several thousand people over a period of at least five years testing them regularly for HIV. For Williams, such studies have not been done, and even in-depth evaluations of the impact of specific prevention programmes have been few and far between. Unfortunately, this type of study will take years to develop, and currently monitoring and evaluation tends to be short-term. In the absence of reliable long-term data, Dr Mulumba believes the key to interpreting HIV/AIDS figures is to understand what is going on in our societies more broadly (AIDS Review, 2009). She suggests that looking at social indicators such as the rates of rape and teenage pregnancies, or the numbers of children completing school, could also provide indirect evidence of behaviour change, or lack of it.
Missing Component in ABC Campaign
Behaviour change programmes to prevent HIV transmission have mainly promoted condom use or abstinence, while the 'be faithful', or partner reduction, component of the ABC campaign had been neglected. For example, although abstinence may be a viable option for many young people, for others it may be an unrealistic expectation. Even though prospective studies have shown that condoms reduce risk by about 80 to 90 percent when always used, in real life they are often used incorrectly or inconsistently.
Changing human behaviour is not an overnight process. In the meantime, technologies old and new, from diaphragms to vaccines, are being investigated in the hope that science will succeed where attempts to alter human behaviour have not done as well as anticipated. However, the issue of prevention should not rest solely on the shoulders of government. The prevention of HIV infections has a great deal to do with individual choice.
References
• AIDS Law Project South Africa, 2009. SANAC adopts HIV & AIDS and STI Strategic Plan for South Africa, 2007-2011.
• http://www.alp.org.za/modules.php?op=modload&name=News&file=article&sid=360
• Chetty, D. & Michel, B. 2008. Turning the tide: A strategic response to HIV/AIDS in South African Higher Education: HEAIDS Programme Report 2002-2004. SAUVCA. Pretoria: Sunnyside.
• Dorrington, R., Bradshaw, D., Johnson, L. & Budlender, D. 2009. The demographic impact of HIV/AIDS in South Africa: National indicators for 2009. Cape Town: Centre for Actuarial Society of South Africa.
• Hargrove, J. 2009. HIV pathologies and long term survival. AIDS Review. Vol 7, No 11 pp 1401-1410.
• UNAIDS/ UNICEF/ WHO. 2007. Children on the Brink 2004: A joint report of new orphan estimates and a framework for action. New York: AEI Press.