The previously reported “Mississippi baby” is a girl with AIDS who is believed to be functionally cured. The baby, who began antiretroviral treatment when she was 30 years old and stopped taking it when she was 18 months old, has not been tested for the virus and was said to have a possible clinical functional cure. But U.S. pediatric HIV experts and government researchers said July 10 that after 27 months without antiretroviral therapy, the child’s viral load was found to have rebounded during a routine checkup.
The National Institute of Allergy and Infectious Diseases (NIAID) organized a teleconference in which the treating physician reported. The rebound was discovered earlier this month. The child, now 46 months old, was restarted on antiviral therapy with zidovudine, lamivudine and nevirapine. So far, she is tolerating the medications without adverse effects. Treatment is reducing the level of the virus in her body. Hanna Gay, a pediatric HIV specialist at the University of Mississippi Medical Center, has been following the child since birth. When she learned that the child’s virus had rebounded in her body 27 months after stopping the medication, it felt like a crushing blow and was very disappointing.
Dr. Anthony, director of NIAID, echoed this sentiment, saying that the child’s condition was a disappointment to health care providers and researchers. He also reminded us that there is still much to learn about the complexity of HIV infection and where the virus hides. In fact, it is unprecedented for a child to remain undetectable for 2 years after stopping antiretroviral therapy, said Dr. Deborah Persaud, professor of infectious diseases at Johns Hopkins Children’s Center, adding that typically, when treatment is stopped, HIV levels rebound after a few weeks, not years. The child was born in 2010 at a clinic in Mississippi. Her mother was not diagnosed with HIV infection until the time of delivery, so she did not receive antiretroviral medication during her pregnancy. Given the infant’s high risk of HIV infection, triple antiretroviral therapy was initiated 30 hours after birth. Tests confirmed that within a few days, the infant was infected with HIV. 2 weeks later, the child was discharged from the hospital and continued on antiretroviral therapy.
The child continued on antiretroviral therapy until 18 months, when the child lost contact and stopped receiving treatment. However, 5 months later, the child’s blood sample was retested by health care providers and no HIV load (less than 20 copies/mL) was detected and no virus-specific antibodies were present. The child had not received antiretroviral medication for more than 2 years, and her viral load remained below detectable levels.
Earlier in the month, an HIV load was detected in the child’s blood (16,750 copies/mL). 72 hours later, the viral load was tested again and confirmed this finding (10,564 copies/mL). In addition, the child’s CD4+ T-cell levels were decreasing and HIV antibodies were present. On the basis of these results, the child was started again on antiretroviral therapy. Viral gene sequence analysis indicated that the child’s HIV infection was of maternal origin. Researchers needed to study why the viral load in the child could be maintained below detectable levels. How can someone remain virally suppressed 27 months after stopping treatment? We know even less about what triggers the replication of the virus. Now the child will have to continue antiretroviral therapy that could last a lifetime.
Dr. Katherine Luzuriaga, professor of pediatrics at the University of Massachusetts Medical School, believes that the long-term failure of the virus to rebound and the absence of a specific immune response suggest that very early antiretroviral therapy can restrain HIV-infected cells. The case of the Mississippi infant suggests that starting antiretroviral therapy early in HIV infection does not completely eliminate HIV-infected cells, but can greatly limit the progression of the virus-infected cells and disease. We must now focus our attention on what keeps the virus persistently at low levels. This will facilitate the understanding of the mechanism of HIV infection and thus the treatment of HIV.