I’m Erika Larson.
I want to get sick so the doctor will give me a grant, and my children will have healthy food. Even if I die, my children will be better taken care of.
These words were spoken by Zolile, one of over 4.8 million HIV-infected South Africans. Her story illustrates the perverse incentives of the South African disability grant program that offers $130 per month to those with a CD4 count of 200 or below. Because grants expire after six months, patients have stopped taking medicine to remain sick in order to receive the grant and feed their families. Selwyn Jehoma, Deputy Director-General of South Africa’s Social Security Department is investigating yet another possible problem the program has created. “There’s another area that we’ve investigated: we’re asking ourselves ‘Are people leaving children with family members for the provisions for a foster care grant. And why are they doing this? Given there is a lack of income and they can’t support their own children, and obviously one would like to look at support systems.” In a country where unemployment soars to nearly 40%, HIV patients are confronted with a desperate choice: a choice between personal health and the well-being of their family.
Decisions like those of Zolile suggest not only inadvertent problems with the welfare program, but consequences of South Africa’s poverty. Destitution increases vulnerability to HIV. Migrant laborers, sex workers, disempowered women, and low education have augmented the spread of the epidemic. In turn, HIV compounds impoverishment. Affected households earn only 50-60% of the income earned by non-affected families. Low incomes, further drained by medical bills and funerals, do not adequately finance nutritional food, thereby increasing the chances for opportunistic infections. South Africa’s dilemma demonstrates that the vicious cycle between poverty and HIV has yet to be broken.
Though solving the problem seems unfathomable, there are alternatives to the disability grant program. When asked about other options, Dr. Peter Hess, Professor of Economic Development at Davidson College, drew from the success of Mexico’s educational conditional cash transfer program. For South Africa, a program would mobilize community health workers to test patients’ CD4 counts before and after medication, measuring their regime adherence and rewarding them for continuing drug therapy. Conditional cash transfers not only lighten the heavy bureaucracy, but also provide a space for positive incentives and community involvement, both essential components to sustainable development.
These South African songs are reminders not only of a profound culture, but also resilient religious and civil societies. Like Brazil, South Africa can draw on both churches and NGOs to create a comprehensive approach, fusing both top-down epidemiology and bottom-up development.
Though President Mbeki’s denial of HIV as the cause of AIDS has created an unredeemable lag in tackling the HIV issue, South Africa can find hope in policies that address HIV, poverty, and malnutrition. By engaging the expansive, young population through education and open dialogue, South Africa can harness one of its most important assets, its people.
Though it may be easy to criticize South Africa, we should ultimately examine our own choices. Have we, as an international community, failed to recognize the link between HIV and poverty? The moral imperative to address AIDS lies beyond science—it can be found in stories like that of Zolile, narratives that are reminders of what it means to be a part of global community.
Tuesday, November 21, 2006
Monday, November 20, 2006
Perspectives on Condom use in Zambia and the U.S.
I’m Steve Halliday.
During the month of July, 2006 I had the opportunity, along with several other Davidson students, to travel to Mwandi, Zambia with the Davidson Biology department. As a part of this trip I had to research and write a paper on the effectiveness of education in preventing HIV/AIDS. Through my experience in the local classrooms, and interviews with hospital workers and community members I realized that the level of HIV awareness and the general knowledge of the disease was very high, but for some reason seemed to have relatively little effect in preventing HIV transmission.
While there are obviously many factors that contribute to this problem, such as abject poverty and lack of access to healthcare, I found that one factor that may play a very large role are the adverse attitudes towards condom use in the community.
The town of Mwandi, which is largely centered around a mission compound, is very Christian. Most everyone in town attends religious services at least once a week, and the mission hospital is the only Western medical institution in the area. While the mission is affiliated with a protestant church, it is still a quite conservative Christian faith, and officially the church does not advocate condom use, except between monogamous married couples. As a result of this the hospital is not supposed to distribute condoms to patients, and it presents a major conflict of interest in the counseling they can offer.
The actual opinions on condom use vary substantially from person to person, based on personal views as well as what they’ve seen in their line of work. For example, the head clinical officer openly advocates condom use, and distributes them as often as he can receive shipments from the ministry of health. But at the same time, he does not believe that condoms should be talked about or distributed to children because he believes it will increase promiscuity.
Condom use is taught in school, but with the caveat that they are not very effective, and the only real way to protect yourself is through abstinence and monogamy. This creates an attitude where condom use is not thought of seriously, and when a child becomes sexually active they are less likely to use a condom.
These attitudes toward condom use are detrimental to public health, and severely decrease the effectiveness of HIV prevention. These attitudes aren’t limited to Mwandi, to Zambia, or even to Africa, but are common throughout the world. The main scapegoat for spreading this sentiment is the Catholic church, which is opposed to condom use on the grounds that premarital and extramarital sex are sins, and the now less common belief
that married couples should only have sex for the purpose of procreating. The Catholic church is certainly not the only organization at fault though, as even the current administration of the United States supports abstinence only education.
This idea of abstinence only education is destructive to sexual education, and contributes to the spread of STDs and unwanted pregnancies, and needs to be abolished worldwide. Condom use should be taught in all schools as a viable means of protection from HIV and STDs should a person decide to have sex, because it has been shown time and time again that simply telling people not to have sex doesn’t work. With the lack of a cure for HIV in the foreseeable future prevention is clearly the most important action that must
be taken, and education centered around safe sex needs to play a central role in prevention policy, along with social welfare programs and the empowerment of women.
During the month of July, 2006 I had the opportunity, along with several other Davidson students, to travel to Mwandi, Zambia with the Davidson Biology department. As a part of this trip I had to research and write a paper on the effectiveness of education in preventing HIV/AIDS. Through my experience in the local classrooms, and interviews with hospital workers and community members I realized that the level of HIV awareness and the general knowledge of the disease was very high, but for some reason seemed to have relatively little effect in preventing HIV transmission.
While there are obviously many factors that contribute to this problem, such as abject poverty and lack of access to healthcare, I found that one factor that may play a very large role are the adverse attitudes towards condom use in the community.
The town of Mwandi, which is largely centered around a mission compound, is very Christian. Most everyone in town attends religious services at least once a week, and the mission hospital is the only Western medical institution in the area. While the mission is affiliated with a protestant church, it is still a quite conservative Christian faith, and officially the church does not advocate condom use, except between monogamous married couples. As a result of this the hospital is not supposed to distribute condoms to patients, and it presents a major conflict of interest in the counseling they can offer.
The actual opinions on condom use vary substantially from person to person, based on personal views as well as what they’ve seen in their line of work. For example, the head clinical officer openly advocates condom use, and distributes them as often as he can receive shipments from the ministry of health. But at the same time, he does not believe that condoms should be talked about or distributed to children because he believes it will increase promiscuity.
Condom use is taught in school, but with the caveat that they are not very effective, and the only real way to protect yourself is through abstinence and monogamy. This creates an attitude where condom use is not thought of seriously, and when a child becomes sexually active they are less likely to use a condom.
These attitudes toward condom use are detrimental to public health, and severely decrease the effectiveness of HIV prevention. These attitudes aren’t limited to Mwandi, to Zambia, or even to Africa, but are common throughout the world. The main scapegoat for spreading this sentiment is the Catholic church, which is opposed to condom use on the grounds that premarital and extramarital sex are sins, and the now less common belief
that married couples should only have sex for the purpose of procreating. The Catholic church is certainly not the only organization at fault though, as even the current administration of the United States supports abstinence only education.
This idea of abstinence only education is destructive to sexual education, and contributes to the spread of STDs and unwanted pregnancies, and needs to be abolished worldwide. Condom use should be taught in all schools as a viable means of protection from HIV and STDs should a person decide to have sex, because it has been shown time and time again that simply telling people not to have sex doesn’t work. With the lack of a cure for HIV in the foreseeable future prevention is clearly the most important action that must
be taken, and education centered around safe sex needs to play a central role in prevention policy, along with social welfare programs and the empowerment of women.
Wednesday, November 15, 2006
Evidence that HIV-2 can infect CD4-negative cells
Human Immunodeficiency Virus Type 2, also known as HIV-2, is prevalent in West Africa and has spread recently to the western coastal region of India and to Europe. Compared to HIV-1 HIV-2’s mortality rate is thought to be a third lower and appears to be closer to the Simian Immunodeficiency Virus or SIV. As of 1999 it is known that all three types of immunodeficiency virus interact in some fashion with the CD4 cell surface and a co-receptor triggered by contact with the viral protein gp120. It is known that HIV-1 uses CCR5 and CXCR4 as its major co-receptors, but SIV and HIV-2 can use other co-receptors besides CCR5 and CXCR4 for infection in CD4+ cells.
Clapham, McKnight, and Weiss in 1992 showed that one strain of HIV-2 was able to successfully fuse cell to cell and have an efficient infection in CD4- human cells, while other strains were still dependent on CD4 or sCD4 (soluble CD4) for fusion. Reeves et al. in June of 1999 wanted to see if primary HIV-2 strains could infect CD4- cells that expressed either CCR5 or CXCR4 receptors.
They began by characterizing the co-receptors used by HIV-1, HIV-2, and SIV strains in CD4+ cells and found that compared to HIV-1, HIV-2 did use a variety of co-receptors for infection in almost all the viral strains but predominately CCR5 and CXCR4. They then tested for CD4-independent infection for the different HIV-2 strains using CD4- cells. The researchers concluded that certain strains could produce an effective infection in the cells using only CCR5 or CXCR4 receptors. To verify this, Reeves et al. used specific ligands of CCR5, CXCR4, and CD4 and confirmed that infection could occur independent of CD4 with CCR5 or CXCR4.
Overall, they found that there were 7 HIV-2 strains that used CCR5 and/or CXCR4 to infect CD4+ cells, but in CD4- cells 2 strains used only CXCR4, 2 strains used only CCR5, and 3 used neither CCR5 nor CXCR4 efficiently.
In comparing HIV-1, HIV-2, and SIV, they showed that HIV-2 and SIV are less reliant on CD4 for infection and that certain strains using CCR5 to infect CD4- cells levels were very similar to SIV strains in CD4 independent infection.
It is unknown why, but astrocytes although not expressing CD4, in vivo can be infected with HIV-1. Reeves et al. then determined whether astrocytes, CD4- cells, were susceptible to infection. Results showed that infection occurred via the CXCR4 receptor and that the concentration of the receptor might play a role in the efficiency of infection.
Thus the ability of HIV-2 to infect a cell independent of CD4 depends on the cell type and the concentration of co-receptors on the cell surface. The researchers note that there could be other receptors or factors that have yet to be identified. Co-receptors could have different conformational changes in different cells or could exist as oligomers, which would influence their activity and identification.
It is theorized that the original SIV and HIV strains used only one receptor and then evolved to the two co-receptor mechanism. This explains the difference between the different types of immunodeficiency viruses and variation of the strains within the sub-types. It is unknown why HIV needs 2 co-receptors to infect a cell, but it does seem selective pressures to gain immune resistance have evolved to make it harder for the body to inhibit viral infection. The fact that there are differences between types and strains make HIV mechanism difficult to understand and makes HIV treatment even more difficult to design.
Jessica Lahre
Reeves, J. et al. (1999). Primary Human Immunodeficiency Virus Type 2 (HIV-2)
Isolates Infect CD4-Negative Cells via CCR5 and CXCR4: Comparison with
HIV-1 and Simian Immunodeficiency Virus and Relevance to Cell Tropism In
Vivo. Journal of Virology. 73 (9): 7795-7804.
Clapham, McKnight, and Weiss in 1992 showed that one strain of HIV-2 was able to successfully fuse cell to cell and have an efficient infection in CD4- human cells, while other strains were still dependent on CD4 or sCD4 (soluble CD4) for fusion. Reeves et al. in June of 1999 wanted to see if primary HIV-2 strains could infect CD4- cells that expressed either CCR5 or CXCR4 receptors.
They began by characterizing the co-receptors used by HIV-1, HIV-2, and SIV strains in CD4+ cells and found that compared to HIV-1, HIV-2 did use a variety of co-receptors for infection in almost all the viral strains but predominately CCR5 and CXCR4. They then tested for CD4-independent infection for the different HIV-2 strains using CD4- cells. The researchers concluded that certain strains could produce an effective infection in the cells using only CCR5 or CXCR4 receptors. To verify this, Reeves et al. used specific ligands of CCR5, CXCR4, and CD4 and confirmed that infection could occur independent of CD4 with CCR5 or CXCR4.
Overall, they found that there were 7 HIV-2 strains that used CCR5 and/or CXCR4 to infect CD4+ cells, but in CD4- cells 2 strains used only CXCR4, 2 strains used only CCR5, and 3 used neither CCR5 nor CXCR4 efficiently.
In comparing HIV-1, HIV-2, and SIV, they showed that HIV-2 and SIV are less reliant on CD4 for infection and that certain strains using CCR5 to infect CD4- cells levels were very similar to SIV strains in CD4 independent infection.
It is unknown why, but astrocytes although not expressing CD4, in vivo can be infected with HIV-1. Reeves et al. then determined whether astrocytes, CD4- cells, were susceptible to infection. Results showed that infection occurred via the CXCR4 receptor and that the concentration of the receptor might play a role in the efficiency of infection.
Thus the ability of HIV-2 to infect a cell independent of CD4 depends on the cell type and the concentration of co-receptors on the cell surface. The researchers note that there could be other receptors or factors that have yet to be identified. Co-receptors could have different conformational changes in different cells or could exist as oligomers, which would influence their activity and identification.
It is theorized that the original SIV and HIV strains used only one receptor and then evolved to the two co-receptor mechanism. This explains the difference between the different types of immunodeficiency viruses and variation of the strains within the sub-types. It is unknown why HIV needs 2 co-receptors to infect a cell, but it does seem selective pressures to gain immune resistance have evolved to make it harder for the body to inhibit viral infection. The fact that there are differences between types and strains make HIV mechanism difficult to understand and makes HIV treatment even more difficult to design.
Jessica Lahre
Reeves, J. et al. (1999). Primary Human Immunodeficiency Virus Type 2 (HIV-2)
Isolates Infect CD4-Negative Cells via CCR5 and CXCR4: Comparison with
HIV-1 and Simian Immunodeficiency Virus and Relevance to Cell Tropism In
Vivo. Journal of Virology. 73 (9): 7795-7804.
Tuesday, November 14, 2006
HIV/AIDS in China
Welcome to this installment of The AIDS Pandemic, a podcast hosted by Dr. David Wessner from the Department of Biology at Davidson College. This is Cara Maguire.
With a population of 1.3 billion people, many of them poor and in heavily concentrated cities, China appears to be a country ripe for the easy spread of HIV/AIDS. In 2000, the estimated HIV-positive population exceeded 500,000, with a growth rate that could peak at 10 million people by 2010. However, today in 2006, the current estimate is 650,000 infected. In comparison, the United States has approximately 1 billion fewer people overall, but has 850,000 infected. How has the Chinese government managed to maintain such low numbers and prevent a healthcare disaster?
Traditionally, China has avoided widespread STD epidemics because of strict policies and conservative morals towards prostitution. For China, the twentieth century was basically drug- and prostitution-free. A theory explaining the recent surge in venereal disease is China’s increasing acceptance of a free market. With the economic reforms instituted in the 1980s came a growing wealthy population and the money to support the drug and sex trades. Although estimates in 2000 put intravenous drug users as 72% of the HIV positive population, more recent numbers suggest this group only makes up 42% of infections. It is difficult to assess the percentage of infections due to the sex trade; however, the two trades are often linked due to women offering sex for drugs.
For many years, the Chinese government was slow to recognize the threat of AIDS. Although drug abuse remained illegal, the penalties were relaxed. These penalties involved a variety of rehabilitation programs ranging from voluntary 10-day treatments to up to three years in a reeducation through labor center. In recent years, the Chinese government has taken several steps to address the growing epidemic more decisively. In 2004, guidelines were published for methadone maintenance treatment and needle exchange programs. Exchange programs provide intravenous drug users with clean needles, while methadone, an oral drug, is used to replace the intravenous drugs altogether. Although these programs are socially liberal (and not condoned in the United States), they were primarily confined to large urban centers.
On March 1st, 2006, the most recent governmental guidelines went into effect. By specifying the responsibilities of all levels of government, the guidelines force local governments to take action against the spread of HIV/AIDS. Governments must now provide free anti-HIV/AIDS drugs for rural and underprivileged patients and free testing and information. In addition, the guidelines protect the rights of patients by forbidding the release of any personal information. Finally, local governments must provide free tuition and fee exemption to AIDS orphans.
Overall, the measures taken by the government have done a good job in helping victims and limiting the spread of HIV in this large country.
With a population of 1.3 billion people, many of them poor and in heavily concentrated cities, China appears to be a country ripe for the easy spread of HIV/AIDS. In 2000, the estimated HIV-positive population exceeded 500,000, with a growth rate that could peak at 10 million people by 2010. However, today in 2006, the current estimate is 650,000 infected. In comparison, the United States has approximately 1 billion fewer people overall, but has 850,000 infected. How has the Chinese government managed to maintain such low numbers and prevent a healthcare disaster?
Traditionally, China has avoided widespread STD epidemics because of strict policies and conservative morals towards prostitution. For China, the twentieth century was basically drug- and prostitution-free. A theory explaining the recent surge in venereal disease is China’s increasing acceptance of a free market. With the economic reforms instituted in the 1980s came a growing wealthy population and the money to support the drug and sex trades. Although estimates in 2000 put intravenous drug users as 72% of the HIV positive population, more recent numbers suggest this group only makes up 42% of infections. It is difficult to assess the percentage of infections due to the sex trade; however, the two trades are often linked due to women offering sex for drugs.
For many years, the Chinese government was slow to recognize the threat of AIDS. Although drug abuse remained illegal, the penalties were relaxed. These penalties involved a variety of rehabilitation programs ranging from voluntary 10-day treatments to up to three years in a reeducation through labor center. In recent years, the Chinese government has taken several steps to address the growing epidemic more decisively. In 2004, guidelines were published for methadone maintenance treatment and needle exchange programs. Exchange programs provide intravenous drug users with clean needles, while methadone, an oral drug, is used to replace the intravenous drugs altogether. Although these programs are socially liberal (and not condoned in the United States), they were primarily confined to large urban centers.
On March 1st, 2006, the most recent governmental guidelines went into effect. By specifying the responsibilities of all levels of government, the guidelines force local governments to take action against the spread of HIV/AIDS. Governments must now provide free anti-HIV/AIDS drugs for rural and underprivileged patients and free testing and information. In addition, the guidelines protect the rights of patients by forbidding the release of any personal information. Finally, local governments must provide free tuition and fee exemption to AIDS orphans.
Overall, the measures taken by the government have done a good job in helping victims and limiting the spread of HIV in this large country.
Tuesday, November 07, 2006
WOMEN AND HIV/AIDS IN AFRICA
Globally, women now constitute 48% of the HIV positive population. 76% of these HIV positive women live in Sub-Saharan Africa, where women account for 59% of adults living with HIV. The rising rates of HIV infection in women and young girls is directly related to their inferior social, economic, and legal status in this region of the world. Women’s autonomy relating to sexual decisions is rarely respected. Men tend to dominate women’s sexuality in Africa’s dramatic context of poverty.
While women are account for half of the HIV burden, many responses to the epidemic have failed to address the social, economic, and cultural factors that put women at an increased risk for HIV infection. The ABC program, which emphasizes Abstinence, Be faithful, and Condom use, has been adopted by many African governments but is simply not feasible for women. They are not given the choice to abstain from sex, but are often raped or coerced into having sex as a means of survival. While they may remain faithful to their husbands, they are powerless to ensure that their husbands remain faithful to them. In addition, women are not given sufficient control over sexual situations to ensure that their partners, particularly their husbands, always wear a condom. Such programs fail to address the social factors limiting women and girl’s sexual autonomy and placing them at an increased risk for HIV.
Violence against women, whether in the context of rape or sexual abuse, is a significant factor in the propagation of HIV in women. Women who have been subjected to violence are three times as likely to be infected with HIV as women who have not. Girls in Africa are also pressured into marrying at a young age. Most of these girls are married to older men who are more likely to have had exposure to sexually transmitted diseases and are less likely to use a condom.
Education efforts need to be extended to women and heavy investments should be made in methods that would allow women to control HIV prevention. Female condoms are very effective in blocking the passage of microorganisms, including HIV. However, these condoms cost on average $0.70, making them ten times more expensive than male condoms. In addition, they are not widely available and most women don’t even know about their existence. Microbicides are a very promising new method of HIV prevention that are able to block or disable the virus as soon as it enters the body and before it spreads. Even the first generation microbicides are expected to reduce HIV transmission by 40 to 60%. A 60% effective microbicide is projected to prevent 2.5 million new HIV infections over a period of three years.
Antiretroviral treatment is now available to 1.3 million people, representing a significant increase in just a few years. Still, ARVs are only available to 17% of the people in Sub-Saharan Africa who need them. Data has not shown that there are significant gender discrepancies in access to treatment, but women do encounter more difficulties in adhering to the regimens. Because women are confronted with more intense stigma and marginalization than men when infected with HIV, many chose not to return to clinics for their test results. They are also afraid that their serostatus will be disclosed without their consent, which in many cases leads to women being kicked out of their homes and losing all economic support. One study in Zambia revealed that 66% of women did not disclose their status to their partner for fear of blame, violence, and abandonment. 76% did not adhere to their treatment regimen because they were trying to hide their pills.
To design more effective AIDS programs, it is essential that more women, especially those living with HIV, be included in international AIDS conferences and meetings where programs are designed. An effective program needs to focus on education, economic empowerment, improved access to health services, and better prevention options for married women. Laws need to be developed to protect women’s rights and allow them to have a reliable legal recourse when those rights are violated. Pressure needs to be brought against social and cultural norms that legitimize child marriage and domestic violence. Programs need to be implemented that recognize the specific challenges faced by HIV positive women and improve their access to reproductive health services. Access to testing and treatment should be facilitated and promises of confidentiality respected. Thankfully, there are feasible steps that can be taken to empower women and address the issues that make them vulnerable to HIV infection.
Lauren Finley
While women are account for half of the HIV burden, many responses to the epidemic have failed to address the social, economic, and cultural factors that put women at an increased risk for HIV infection. The ABC program, which emphasizes Abstinence, Be faithful, and Condom use, has been adopted by many African governments but is simply not feasible for women. They are not given the choice to abstain from sex, but are often raped or coerced into having sex as a means of survival. While they may remain faithful to their husbands, they are powerless to ensure that their husbands remain faithful to them. In addition, women are not given sufficient control over sexual situations to ensure that their partners, particularly their husbands, always wear a condom. Such programs fail to address the social factors limiting women and girl’s sexual autonomy and placing them at an increased risk for HIV.
Violence against women, whether in the context of rape or sexual abuse, is a significant factor in the propagation of HIV in women. Women who have been subjected to violence are three times as likely to be infected with HIV as women who have not. Girls in Africa are also pressured into marrying at a young age. Most of these girls are married to older men who are more likely to have had exposure to sexually transmitted diseases and are less likely to use a condom.
Education efforts need to be extended to women and heavy investments should be made in methods that would allow women to control HIV prevention. Female condoms are very effective in blocking the passage of microorganisms, including HIV. However, these condoms cost on average $0.70, making them ten times more expensive than male condoms. In addition, they are not widely available and most women don’t even know about their existence. Microbicides are a very promising new method of HIV prevention that are able to block or disable the virus as soon as it enters the body and before it spreads. Even the first generation microbicides are expected to reduce HIV transmission by 40 to 60%. A 60% effective microbicide is projected to prevent 2.5 million new HIV infections over a period of three years.
Antiretroviral treatment is now available to 1.3 million people, representing a significant increase in just a few years. Still, ARVs are only available to 17% of the people in Sub-Saharan Africa who need them. Data has not shown that there are significant gender discrepancies in access to treatment, but women do encounter more difficulties in adhering to the regimens. Because women are confronted with more intense stigma and marginalization than men when infected with HIV, many chose not to return to clinics for their test results. They are also afraid that their serostatus will be disclosed without their consent, which in many cases leads to women being kicked out of their homes and losing all economic support. One study in Zambia revealed that 66% of women did not disclose their status to their partner for fear of blame, violence, and abandonment. 76% did not adhere to their treatment regimen because they were trying to hide their pills.
To design more effective AIDS programs, it is essential that more women, especially those living with HIV, be included in international AIDS conferences and meetings where programs are designed. An effective program needs to focus on education, economic empowerment, improved access to health services, and better prevention options for married women. Laws need to be developed to protect women’s rights and allow them to have a reliable legal recourse when those rights are violated. Pressure needs to be brought against social and cultural norms that legitimize child marriage and domestic violence. Programs need to be implemented that recognize the specific challenges faced by HIV positive women and improve their access to reproductive health services. Access to testing and treatment should be facilitated and promises of confidentiality respected. Thankfully, there are feasible steps that can be taken to empower women and address the issues that make them vulnerable to HIV infection.
Lauren Finley
Monday, November 06, 2006
The Influence of Viral Factors on Long-term Nonprogressing HIV
The progression of HIV infection varies from one individual to another. Although “the median time from infection to development of AIDS is 8 to 10 years,” some individuals, known as long-term nonprogressors, fail to develop AIDS after infection with HIV (Hogan and Hammer, 2001). These individuals have been identified on various continents, and include persons with various types of exposure, such as commercial sex workers, hemophiliacs who have received HIV positive blood during transfusions, infants born to seropositive mothers, health care professionals accidentally infected by needlestick, intravenous drug users, and sexual partners of known HIV positive individuals (Zhu et al., 2002). Despite prolonged periods of HIV infection, long-term nonprogressors “remain asymptomatic and have normal CD4 cell counts and low or undetectable viral loads,” (Hogan and Hammer, 2001). The existence of long-term nonprogressors indicates the possibility of a natural immunity to HIV (Haynes et al., 1996). Though current research suggests a broad range of potential viral and host factors that may influence progression rates, further investigation is necessary to clarify the roles of each of these factors and elucidate how this knowledge can be applied to the therapeutic development of vaccines (Hogan and Hammer, 2001). This podcast will focus solely on the influence of viral factors.
Research has indicated that certain characteristics of the HIV-1 virus may affect transmission and progression rates. These factors include viral tropism, viral escape, viral attenuation, and viral subtype. Two variants of viral tropism have been identified for the HIV-1 virus, which are macrophage-tropic (M tropic) and T-cell-tropic (T-tropic). Early HIV infection usually results from M-tropic strains. As the virus mutates, its phenotype may change, resulting in a T-tropic strain, which is known to increase the rate of T-cell depletion. The progression from one tropism to the other has been associated with increased pathogenicity and progressive disease (Connor and Ho, 1994).
Another factor that has been linked to disease progression is viral escape from immune response. Viral escape may result from mutations that arise in the gag, pol, and env genes, allowing the virus to elude intense cell-mediated and humoral immune response (Hogan and Hammer, 2001). Additionally, attenuated HIV-1 viruses have been linked with slowed progression of AIDS infection. More specifically, a group of individuals infected with a strain of HIV-1 with a deletion in the nef gene have been identified. When discovered, all eight individuals infected with this strand of HIV-1 appeared to have nonprogressive infection. Upon tracking these individuals, however, the disease reflects slowed progression (Learmont et al., 1992). Further investigation into attenuated strains may present methods that can be used to delay progression of HIV-1 and prolong the lives of infected individuals.
Finally, individuals with different viral subtypes may experience slowed or enhanced disease progression. Epidemiologic studies seeking differences between subtypes are difficult and often inconclusive. However, there is evidence suggesting that HIV-2, a related human retrovirus, is less virulent and less infective, supporting the notion that HIV subtypes may have differential risks associated with transmission and pathogenicity (Marlink et al., 1994).
Although the role of viral factors has not led to conclusive evidence that slows the progression HIV infection to the development of AIDS, continued research of the virus and host may clarify key features of the disease that may aid in the development of vaccines or treatments that induce individuals to acquire the mutations that long-term nonprogressors have obtained naturally (Hammer and Hogan, 2001).
Thanks for listening. I'm Christie Brough.
References
Connor, R.I. and Ho, D.D. (1994). Human immunodeficiency virus type 1 variants with increased replicative capacity develop during the asymptomatic stage before disease progression. Journal of Virology 68:4400-4408.
Haynes, B.F., Pantaleo, G., and Fauci, A.S. (1996). Toward and understanding of the correlates of protective immunity to HIV infection. Science 271:324-328.
Hogan, C.M. and Hammer, S.M. (2001). Host determinants in HIV infection and disease (Part 1: Cellular and humoral immune responses). Annals of Internal Medicine 134:761-776.
Learmont, J., Tindall, B., Evans, L., Cunningham, A., Cunningham, P., Wells, J., et al. (1992). Long-term symptomless HIV-1 infection in recipients of blood products from a single donor. Lancet 340:863-867.
Marlink, R., Kanki, P., Thior, I., Travers, K., Eisen, G., Siby, T., et al. (1992). Reduced rate of disease development after HIV-2 infection as compared to HIV-1. Science 265:1587-1590.
Zhu, T., Corey, L., Hwangbo, Y., Lee, J.M., Learn, G.H., Mullins, J.I., and McElrath, M.J. (2003). Persistence of extraordinarily low levels of genetically homogeneous human immunodeficiency virus type 1 in exposed seronegative individuals. Journal of Virology 77:6108-6116.
Research has indicated that certain characteristics of the HIV-1 virus may affect transmission and progression rates. These factors include viral tropism, viral escape, viral attenuation, and viral subtype. Two variants of viral tropism have been identified for the HIV-1 virus, which are macrophage-tropic (M tropic) and T-cell-tropic (T-tropic). Early HIV infection usually results from M-tropic strains. As the virus mutates, its phenotype may change, resulting in a T-tropic strain, which is known to increase the rate of T-cell depletion. The progression from one tropism to the other has been associated with increased pathogenicity and progressive disease (Connor and Ho, 1994).
Another factor that has been linked to disease progression is viral escape from immune response. Viral escape may result from mutations that arise in the gag, pol, and env genes, allowing the virus to elude intense cell-mediated and humoral immune response (Hogan and Hammer, 2001). Additionally, attenuated HIV-1 viruses have been linked with slowed progression of AIDS infection. More specifically, a group of individuals infected with a strain of HIV-1 with a deletion in the nef gene have been identified. When discovered, all eight individuals infected with this strand of HIV-1 appeared to have nonprogressive infection. Upon tracking these individuals, however, the disease reflects slowed progression (Learmont et al., 1992). Further investigation into attenuated strains may present methods that can be used to delay progression of HIV-1 and prolong the lives of infected individuals.
Finally, individuals with different viral subtypes may experience slowed or enhanced disease progression. Epidemiologic studies seeking differences between subtypes are difficult and often inconclusive. However, there is evidence suggesting that HIV-2, a related human retrovirus, is less virulent and less infective, supporting the notion that HIV subtypes may have differential risks associated with transmission and pathogenicity (Marlink et al., 1994).
Although the role of viral factors has not led to conclusive evidence that slows the progression HIV infection to the development of AIDS, continued research of the virus and host may clarify key features of the disease that may aid in the development of vaccines or treatments that induce individuals to acquire the mutations that long-term nonprogressors have obtained naturally (Hammer and Hogan, 2001).
Thanks for listening. I'm Christie Brough.
References
Connor, R.I. and Ho, D.D. (1994). Human immunodeficiency virus type 1 variants with increased replicative capacity develop during the asymptomatic stage before disease progression. Journal of Virology 68:4400-4408.
Haynes, B.F., Pantaleo, G., and Fauci, A.S. (1996). Toward and understanding of the correlates of protective immunity to HIV infection. Science 271:324-328.
Hogan, C.M. and Hammer, S.M. (2001). Host determinants in HIV infection and disease (Part 1: Cellular and humoral immune responses). Annals of Internal Medicine 134:761-776.
Learmont, J., Tindall, B., Evans, L., Cunningham, A., Cunningham, P., Wells, J., et al. (1992). Long-term symptomless HIV-1 infection in recipients of blood products from a single donor. Lancet 340:863-867.
Marlink, R., Kanki, P., Thior, I., Travers, K., Eisen, G., Siby, T., et al. (1992). Reduced rate of disease development after HIV-2 infection as compared to HIV-1. Science 265:1587-1590.
Zhu, T., Corey, L., Hwangbo, Y., Lee, J.M., Learn, G.H., Mullins, J.I., and McElrath, M.J. (2003). Persistence of extraordinarily low levels of genetically homogeneous human immunodeficiency virus type 1 in exposed seronegative individuals. Journal of Virology 77:6108-6116.
Thursday, November 02, 2006
HIV/AIDS in the Southeastern U.S.
The southern United States is a region both famous for fried chicken, sweet tea, and a slow pace of life, yet notorious for its religious conservatism and a history of slavery and segregation. The South has gained another reputation in the past few years, however, that is not so widely known: it is quickly becoming the center of the HIV/AIDS epidemic in the United States.
One reason why AIDS prevalence in the south has gone unnoticed for so long is that the average southerner doesn’t think the epidemic can affect them. Most associate HIV with large urban cities, like New York City, San Francisco, and Los Angeles, places that don’t have much in common with small southern towns. They also still see AIDS as a “gay disease” and are generally uneducated about HIV and what it means to be HIV+.
The southern region of the United States, as defined by the US Census Bureau, includes 16 states and the District of Columbia. The Deep South represents a group of six southern states (Alabama, Georgia, Louisiana, Mississippi, South Carolina, and North Carolina) that are disproportionately affected by the AIDS epidemic. From 2000-2003, CDC estimates show a 35% increase in new reported AIDS cases in the Deep South, but only a 5.2% increase nationally. The Deep South also has some of the highest AIDS death rates in the country.
Other health indicators, such as measures of diabetes prevalence, stroke rate, heart disease deaths, infant mortality and preterm births also show high mortality rates in the Deep South. Furthermore, the Deep South also has very high levels of STD infection. The Kaiser Family Foundation reported that in 2002, the five states with the highest rates of gonorrhea were all in the Deep South; these states also had high rates of chlamydia and syphilis. STD prevalence is of particular importance because the presence of an STD facilitates HIV transmission.
Since its discovery, HIV has disproportionately attacked socially marginalized groups, starting with the gay community and spreading to the poor and disenfranchised. Deep South states generally have higher poverty rates than other regions. Poverty contributes HIV/AIDS rates because individuals do not have access to health education or preventative services and cannot afford treatment. Poverty has also been associated with drug use, which can lead to HIV transmission through the sharing of needles.
The south also experiences a large number of rural HIV/AIDS cases. The 1995 US Census estimated that 43% of people living in the south live in rural areas. In rural areas it is often hard to find nearby healthcare, and many patients won’t or can’t get to services. This leads to late diagnosis and unintentional infection of others.
Nearly 80% of new AIDS cases in the South are among African Americans. The HIV/AIDS epidemic is concentrated in poor communities, where African Americans are disproportionately represented. This is particularly true in the Deep South, where populations are approximately 30% Black, compared to the 18.5% in other southern states. Overall, 25% of African Americans live in poverty and are 1.5 times more likely than Whites to lack health insurance. Medical and social service barriers for African Americans are not uncommon in the rural South, and access to HIV medication and care is no exception. Many African Americans feel distrust and anger towards the healthcare system due to historical oppression and enduring medical inequalities. This has led to conspiracy theories that are believed by even the most educated and has created barriers for HIV prevention.
HIV prevalence in the Deep South cannot be studied without a look at historical and cultural factors as well. Many people often blame the lack of medical professionals and poor access to healthcare for the South’s high HIV rates, yet the South is just as rural as the Midwest and does not have fewer health providers than other rural areas. The southern “culture of politeness” prevents discussion of topics that are deemed offensive, such as sex and homosexuality. Religious conservatism also contributes to the spread of HIV by affecting education. Many schools teach abstinence-only curriculums and don’t provide information about other forms of protection, putting youth at risk for infection. Religious conservatism is also associated with close-mindedness, which increases the perceived HIV stigma.
In the end it is important to consider all possible causes of AIDS prevalence in the Deep South states in order to provide more effective preventative and treatment services to everyone who is afflicted by HIV.
Sources:
Adams B. Polite to a Fault? HIV Plus.com May 2003; http://www.hivplusmag.com/column.asp?id=49&categoryid=1.
Adams B. The South Has Risen. HIV Plus.com May 2003; http://www.hivplusmag.com/column.asp?id=48&categoryid=1.
CDC. Fact Sheet: HIV/AIDS Among African Americans. Feb 2006. http://www.cdc.gov/hiv/topics/aa/resources/factsheets/aa.htm.
Reif S, Geonnotti KL, Whetten K. HIV Infection and AIDS in the Deep South. Am J Public Health 2006; 96: 970-973.
Whetten, K, Nguyen, T. You’re the first one I’ve told: new faces of HIV in the South. New Brunswick: Rutgers University Press.
One reason why AIDS prevalence in the south has gone unnoticed for so long is that the average southerner doesn’t think the epidemic can affect them. Most associate HIV with large urban cities, like New York City, San Francisco, and Los Angeles, places that don’t have much in common with small southern towns. They also still see AIDS as a “gay disease” and are generally uneducated about HIV and what it means to be HIV+.
The southern region of the United States, as defined by the US Census Bureau, includes 16 states and the District of Columbia. The Deep South represents a group of six southern states (Alabama, Georgia, Louisiana, Mississippi, South Carolina, and North Carolina) that are disproportionately affected by the AIDS epidemic. From 2000-2003, CDC estimates show a 35% increase in new reported AIDS cases in the Deep South, but only a 5.2% increase nationally. The Deep South also has some of the highest AIDS death rates in the country.
Other health indicators, such as measures of diabetes prevalence, stroke rate, heart disease deaths, infant mortality and preterm births also show high mortality rates in the Deep South. Furthermore, the Deep South also has very high levels of STD infection. The Kaiser Family Foundation reported that in 2002, the five states with the highest rates of gonorrhea were all in the Deep South; these states also had high rates of chlamydia and syphilis. STD prevalence is of particular importance because the presence of an STD facilitates HIV transmission.
Since its discovery, HIV has disproportionately attacked socially marginalized groups, starting with the gay community and spreading to the poor and disenfranchised. Deep South states generally have higher poverty rates than other regions. Poverty contributes HIV/AIDS rates because individuals do not have access to health education or preventative services and cannot afford treatment. Poverty has also been associated with drug use, which can lead to HIV transmission through the sharing of needles.
The south also experiences a large number of rural HIV/AIDS cases. The 1995 US Census estimated that 43% of people living in the south live in rural areas. In rural areas it is often hard to find nearby healthcare, and many patients won’t or can’t get to services. This leads to late diagnosis and unintentional infection of others.
Nearly 80% of new AIDS cases in the South are among African Americans. The HIV/AIDS epidemic is concentrated in poor communities, where African Americans are disproportionately represented. This is particularly true in the Deep South, where populations are approximately 30% Black, compared to the 18.5% in other southern states. Overall, 25% of African Americans live in poverty and are 1.5 times more likely than Whites to lack health insurance. Medical and social service barriers for African Americans are not uncommon in the rural South, and access to HIV medication and care is no exception. Many African Americans feel distrust and anger towards the healthcare system due to historical oppression and enduring medical inequalities. This has led to conspiracy theories that are believed by even the most educated and has created barriers for HIV prevention.
HIV prevalence in the Deep South cannot be studied without a look at historical and cultural factors as well. Many people often blame the lack of medical professionals and poor access to healthcare for the South’s high HIV rates, yet the South is just as rural as the Midwest and does not have fewer health providers than other rural areas. The southern “culture of politeness” prevents discussion of topics that are deemed offensive, such as sex and homosexuality. Religious conservatism also contributes to the spread of HIV by affecting education. Many schools teach abstinence-only curriculums and don’t provide information about other forms of protection, putting youth at risk for infection. Religious conservatism is also associated with close-mindedness, which increases the perceived HIV stigma.
In the end it is important to consider all possible causes of AIDS prevalence in the Deep South states in order to provide more effective preventative and treatment services to everyone who is afflicted by HIV.
Sources:
Adams B. Polite to a Fault? HIV Plus.com May 2003; http://www.hivplusmag.com/column.asp?id=49&categoryid=1.
Adams B. The South Has Risen. HIV Plus.com May 2003; http://www.hivplusmag.com/column.asp?id=48&categoryid=1.
CDC. Fact Sheet: HIV/AIDS Among African Americans. Feb 2006. http://www.cdc.gov/hiv/topics/aa/resources/factsheets/aa.htm.
Reif S, Geonnotti KL, Whetten K. HIV Infection and AIDS in the Deep South. Am J Public Health 2006; 96: 970-973.
Whetten, K, Nguyen, T. You’re the first one I’ve told: new faces of HIV in the South. New Brunswick: Rutgers University Press.
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