In a setback to hopes for a cure for HIV, a child in Mississippi whom scientists thought was cured of the disease showed signs of infection with the virus again last year.
The case was first reported in 2013, and it was hailed as a "game changer" in the fight against Aids, or the acquired immune deficiency syndrome.
The toddler was born to a mother who was diagnosed HIV-positive just before delivery. HIV refers to the human immunodeficiency virus, which causes Aids.
Doctors administered high doses of antiretroviral drugs - which help to decrease levels of the virus in patients' bodies - 30 hours before she was born.
The girl, who is now five years old, remained on the antiretroviral drugs for only about 18 months. A few months later, doctors said the girl had no evidence of the life-threatening disease in her blood.
Researchers said the girl was the first child to be "functionally cured" of HIV, which means that the amount of virus is so small that life-long treatment is not needed.
But in July last year, when she was four, tests detected HIV antibodies in the child again.
Dr Hannah Gay, a paediatric HIV specialist at the University of Mississippi Medical Centre, was quoted as saying: "It felt like a punch to the gut. It was extremely disappointing from both the scientific standpoint ... but mainly for the sake of the child who is back on medicine and expected to stay on medicine for a very long time."
This article was first published on Nov 20, 2015.
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