Testing and Treatment of HIV/AIDS in Children

According to a 2006 UNAIDS/WHO AIDS Epidemic Update, there are approximately 39.5 million people living with HIV/AIDS throughout the world. Of those infected, 2.3 million are aged 15 or younger. Approximately 90% of children infected with HIV acquire the virus perinatally, meaning it is transmitted from a mother to her child during pregnancy, labor, delivery or through breastfeeding. According to the CDC, the prevalence of mother-to-child transmission of AIDS in the US has dropped significantly due to effective testing of pregnant women and treatment of those found to be infected; in resource poor settings, however, the testing and treatment of infected women is far less common. In 2005, the UNAIDS/WHO AIDS Epidemic Update found that only 9% of pregnant women in resource poor countries were offered any sort of prevention services, leading to a higher prevalence of pediatric HIV/AIDS infection in less developed countries. As the prevalence of women of childbearing age who are infected with HIV increases in resource poor settings, it can be expected that the number of babies infected from mother-to-child transmission will likewise increase.

Children infected with HIV/AIDS are confronted with an extremely high rate of illness and death. The World Health Organization has found that because of their unique metabolic and immunologic circumstances, HIV progresses rapidly in children, with an estimated one third of infants dying by the time they reach their first birthday and half dying by their second birthday. Although in most developed countries identification and treatment of HIV infected babies is quite successful, which allows those children to lead healthier and longer lives, the situation is quite different in resource poor countries where testing, much less treatment of infants and children is relatively unavailable. To begin with, testing may be unavailable to individuals in developing countries due to the distance, expense and impracticality of reaching those hospitals and clinics that provide testing. Even when testing is locally available, parents may be unwilling to test their babies for fear of stigma and prejudice associated with an HIV positive status. Furthermore, testing of infants in developing countries can require far more time than in developed countries. PCR tests are among the fastest and most effective ways to diagnose infants as they can be done within 48 hours of birth and results are available to the mother within 6 weeks of the completion of the test. PCR tests are rarely accessible and prohibitively expensive in resource poor settings where antibody tests are the norm. These antibody tests only begin to give accurate results 18 months after birth, and so babies in developing countries are oftentimes diagnosed far later than in developed countries, if they are diagnosed at all.

Aside from the difficulties in testing infants and children for HIV in resource poor settings, there continues to be a dearth of treatment for children found to be positive for the virus. Although both prophylaxis and HAART or highly active antiretroviral therapy can be extremely effective in treating HIV/AIDS and preventing opportunistic infections in children, the unique difficulties associated with treating children in resource poor settings mean that these therapies are widely underused. UNAIDS found in 2006 that “an estimated 380,000 children died of AIDS-related causes” and that, “the vast majority of these deaths could have been prevented either by treating opportunistic infections or providing HAART.” Similarly, a UNAIDS/WHO report found that nearly 90% of children who could benefit from ARV treatments are not currently receiving it. This lack of treatment can be attributed to several factors.

In many resource poor settings, antiretroviral treatment may simply be unavailable. Those countries where the HIV/AIDS burden is greatest such as in Sub-Saharan Africa are oftentimes the least able to provide treatment, and so a lack of resources oftentimes translates into a lack of prophylaxis and/or antiretrovirals. Prophylaxis has been found to be extremely effective in staving off opportunistic infections in HIV positive children and is useful in delaying the need for HAART in pediatric populations. Although prophylactic drugs are widely available and relatively cheap, a UNAIDS/WHO study has found that currently nearly 4 million children who could benefit from such treatment are not receiving it. This is probably the result of lack of available treatment sites and infrastructure in resource poor settings. This dearth of available treatment translates to ARVs as well as prophylactic treatments. Even in areas where adult ARV treatment is present, there is rarely a comparable pediatric treatment site. This is due to the fact that suitable pediatric drug formulations are oftentimes prohibitively expensive and impractical. Little research had been conducted in the area of pediatric dosages because in the developed world effective mother to child prevention had limited the need for pediatric ARVs. Because so few drugs are available in pediatric dosages, and those that are available tend to be far more expensive than those made for adults, most caregivers in resource poor settings are limited to providing either expensive and unpleasant tasting syrup formulas or cutting and crushing adult tablets to provide ARVs for their pediatric patients. Crushing the pills provides an inexact measure of the amount of medication that is administered. Since under dosage can result in resistance of the virus to the drugs, and over dosage can result in amplified side-effects, the lack of correct dosages inherent in using adult drugs for pediatric patients means this mode of drug administration is far from ideal.

Important steps have been taken to begin to provide better treatment for pediatric AIDS patients. In August of 2007 the US Food and Drug Administration (FDA) approved a special tablet for children with HIV that combines three antiretroviral drugs into one pill. The tablet can be dissolved in water for ease of administration which is required only twice a day. The drug is produced by the manufacturer Cipla Limited, a generic pharmaceutical company based in India. Though unapproved for use in the US, the drug has been authorized for use in developing countries where the need and demand is greatest. Despite the enormous implications for successful treatment of pediatric AIDS that this drug will bring, there are still substantial obstacles to be overcome before pediatric care and treatment of AIDS is fully complete. Mother-to-child transmission must be diminished in resource poor settings. In situations where prevention of mother-to-child transmission is not achieved, suitable infrastructure for administration of prophylactic and antiretroviral drugs to pediatric patients must be established. Movements and groups such as the “Stop AIDS in Children” campaign are working towards prevention of mother-to-child transmission and improvement of treatment for infected children. With support of both developed and resource poor countries, the relatively ignored problem of HIV/AIDS in children can be successfully addressed.

Until next time, this is Dominique Maietta for the AIDS Pandemic Podcast.

Refrigeration and HIV Meds in Resource-limited Settings

I'm Charlie Raver.

One of the distinguishing characteristics between the AIDS epidemic in the developed world and that in Africa and the developing world is a simple lack of the infrastructure to deal with the disease. Infrastructure includes everything from roads to electricity to hospitals. One example that most of us rarely think of as a gift, couldn’t dream of walking into a home and not finding, and would be lost without is something to which many in the developing world do not have access. What am I talking about? Refrigeration. Without this amazing piece of technology we would not be able to easily enjoy fresh meats, fish, dairy, and many simple nutritional luxuries that we as Americans take for granted. In addition to problems with food preservation, hospitals and health clinics would be unable to store blood, vaccines, heat intolerant medicines, and many laboratory supplies.

For many in the developing world that is exactly the problem. Without refrigeration they have no means to store many of the supplies necessary for maintaining a health clinic. Without this infrastructure, access to basic care, essential for the treatment of AIDS, is extremely limited. Recently, the WHO recommended the use of a ritonavir boosted protease inhibitor as part of the drug regimen. Aside from being able to obtain the drug, one problem is that ritonavir requires refrigeration in hot climates. Currently only one of the ritonavir boosted PIs is available in a heat stable form which, obviously puts a huge constraint on the availability of the drug in the developing world. A confounding issue is the high rates of coinfection of diseases such as tuberculosis and malaria in these resource poor areas. In addition to proper care, access to testing for HIV and TB has been cited as one of the first obstacles to fighting the epidemic. The WHO estimates that less than 10% of people living with HIV/AIDS in parts of Sub-Saharan Africa are aware of their HIV status.

In addition to poor access to health care, the epidemic is only made worse by the staggering rates of malnutrition. In their recommendations for antiretroviral therapy, the WHO emphasized the importance of nutrition not just for the overall health of the affected individuals but also because of the link between nutrition and the effectiveness of ART. However, in some parts of Sub-Saharan Africa, it is estimated that as much as 50% of the population is malnourished. Many Africans do not even have the means to buy or grow the most basic foods. This problem is again only made worse by the lack of refrigeration. Some form of food preservation could allow rural communities and individuals to grow crops in excess and store the surplus to either sell and trade with other communities or even just maintain a supply during the non-productive parts of the year. However, when you consider that over 500 million people in Sub-Saharan Africa do not have access to electricity the idea of refrigeration is a long shot.

Unfortunately providing those in rural Africa with electricity is a problem unto itself. Without economic stability there is little room for expansion and improvement of infrastructure whether it is roads, electricity or health care. These lacks in infrastructure only make the AIDS epidemic harder to fight which further hinders economic growth. However, small improvements like access to refrigeration could be a catalyst for change.

One type of refrigeration that requires no electricity is sorption refrigeration. This form of refrigeration works by having two chambers connected by some type of tube. One chamber, the hot side, contains an absorbent material. The other chamber, the cold side, contains a refrigerant. The tube connecting the two would be filled with refrigerant vapor. The vapor in the tube is then absorbed on the hot side causing a drop in pressure in the connecting tube. This causes evaporation of the refrigerant which in the process absorbs heat and causes cooling on the cold side. This continues until all the refrigerant has vaporized and been absorbed on the hot side. To restart the cooling process, the hot side must be heated gently to drive the refrigerant vapor out of the absorbent material and back to the cold side. In the late 1920s, Powell Crosley Jr. developed a commercial version using ammonia and water that was used throughout the rural United States prior to wide-spread access to electricity. Although this is by no means a large scale solution to the infrastructure problem, adaptation of these ideas for use in the developing world could provide one of the basic necessities for health care and food preservation.