The HIV Baby: Why Is An AIDS Cure So Elusive?
In 2010, Dr. Hannah Gay acted swiftly and boldly, treating the “Mississippi baby” with a heavy dose of antiretroviral therapy (ART) after physicians learned the little girl was born to a mother infected with human immunodeficiency virus type 1, or HIV-1. In the United States, pregnant women known to have HIV are aggressively treated to reduce the risk of mother-to-child transmission to less than one percent. However, this mother was not aware of her HIV status and did not receive prenatal care.
Therefore, Dr. Gay, a pediatric HIV specialist at the University of Mississippi Medical Center in Jackson, decided to act quickly. Three different antiretroviral drugs were given to the infant 30 hours after birth. Dr. Gay hoped that this action would stave off an HIV infection in the child.
The decision was risky. The odds of the baby girl contracting HIV from her mother was 25 percent, ART is not without side effects, and this action defied standard treatment protocols.
Levels of the virus at 13 hours after birth were detected at threshold levels, meaning the child was considered to be suffering from an HIV-infection. However, the amount of virus seemed to decline over the following days, falling below detectable levels at 29 days of age. Medications were continued until the infant was 18 months old and signs of the virus remained undetectable through 30 months of age, which the team reported in the New England Journal of Medicine. The “Mississippi baby” seemed to be cured of HIV. This one-of-a-kind case suggested that extremely early ART in infants may weaken HIV’s ability to develop a firm, and dangerous, hold in a baby’s body.
The news was hailed with great media fanfare, as a true cure for HIV continues to escape scientists and the medical community. A federally funded clinical trial, where Dr. Gay’s early-start method would be tested, was planned. The excitement makes sense. A diagnosis of HIV, though no longer a death sentence, relegates a child to a challenging life—full of hospital visits, terrible medication-induced side effects, and an unbelievable social stigma.
However, it seems this well-intentioned excitement may have been premature. Two months before her fourth birthday, the girl’s pediatricians observed a dip in the number of her CD4+ T-cells—the cells that HIV attacks and kills. Their fears were confirmed when a test for the virus itself came back positive. Her doctors have started her back on ART, on which she will remain for the foreseeable future.
ART, as mentioned above, stands for antiretroviral therapy. HIV, is a retrovirus, which means it has to turn its genetic material, which is made of RNA—similar, yet notably different from DNA (human’s genetic material)—into DNA to effectively infect human cells.
ART usually involves the use of replication process to combat the virus’ ability to infect more cells. These drugs are named for the part of the viral life cycle that they disrupt. For example, the first HIV drug, AZT, belonged to a class of drugs known as nucleoside reverse transcriptase inhibitors (NRTIs). NRTIs inhibit the protein that allows HIV to reproduce its genetic material, which is essential for viral replication. Other classes of drugs involve non-nucleoside reverse transcriptase inhibitors, protease inhibitors, entry or fusion inhibitors, and integrase inhibitors. Modern ART involves the use of combinations of these different drugs to achieve a multi-pronged attack on HIV. The virus can develop resistance to certain drugs, thus a wide and growing arsenal of antiretroviral drugs is crucial.
This finding is obviously a disappointment to the child’s doctors, family, and the wider scientific community. The side effects of ART are significant, so if the length of ART could be limited, the better the quality of life for the child. Though these effects depending on the drug in question, side effects are common and range from severe nausea to peripheral nerve damage to liver and kidney damage. If there is a way to spare anyone, especially a child with a long lifetime ahead of her, from these side effects, it must be explored.
A cure for HIV remains elusive. To date, the only record of a true HIV cure was in Timothy Brown, known for years as the “Berlin patient.” Brown was treated for leukemia, which involved wiping out his bone marrow, the birthplace of blood cells, and replacing it with marrow from a donor who happened to have a genetic mutation that made CD4+ T-cells that lacked a specific receptor. That receptor, CCR5, just so happened to be used by HIV to enter the cell. As the new bone marrow took hold in Brown, it repopulated his body with cells there would not let HIV in or HIV-resistant, functionally curing him.
Efforts to cure HIV range from vaccine to drugs to genetic manipulations. However, some have not worked and others are still cutting their teeth the laboratory.
Nearly 70 million people have acquired HIV since the epidemic was first identified. The disease was a death sentence at the hands of opportunistic infections that took advantage of patients’ HIV-weakened immune systems. Today, those who have access to the proper ART medications and the fortitude to brave the challenging side effects can live otherwise normal lives. Dr. Gay and her team were tantalizingly close to saving the hundreds of thousands of HIV-positive babies born each year from a lifetime of ART. One important fact is unchanged— if a cure for HIV is to be found, it will come from doctors, scientists, and patients who work day in and day out, push the boundaries of medicine, and explore unconventional ideas to bring an end to this disease.