The polymerase chain reaction (PCR) has played a role in the first ever documented case of a child infected with HIV apparently being ‘cured’.


Baby's foot


The child’s mother was HIV positive, though she wasn’t aware of this until she was tested while in labour, and the child, born in Mississippi, was diagnosed with HIV infection at birth, using standard HIV DNA PCR and plasma viral load. When a pregnant woman is known to be HIV positive, she is usually given antiretroviral drugs to prevent her from passing the infection on to the baby, but in this case, it was too close to birth for it to work.

Unusually, the baby received an aggressive course of three antiretroviral drugs from 30 hours after birth. Even though the mother stopped giving the drugs to the child after 18 months, when the child came back into hospital at 23 months, the viral load was undetectable, even with a battery of the most sensitive tests available, including ultrasensitive HIV DNA droplet digital PCR, plasma viral load (single copy) assays, and quantitative co-culture assays.

“The child’s paediatrician in Mississippi was aware of the work we were doing, and quickly notified our team as soon as this young patient’s case came to her attention,” said Rowena Johnston, sponsor amfAR’s vice president and director of research.


HIV virion

Source: NIH, redrawn by Carl Henderson

The negative result came as a surprise to the doctors, as they had expected that the viral levels would have risen significantly, and has been described as a functional cure (when standard tests can find no virus but it is likely that a trace remains in the body).

The researchers believe that this unnamed baby now has the chance of a healthy life without having to rely on anti-HIV medication. This is a single case so no firm conclusions can be drawn. However, it appears that the early treatment stopped HIV from infecting the CD4 cells, the white blood cells that harbour HIV long-term.

If the results can be replicated, this case in Mississippi could point to a potential low-cost approach to treating HIV infection in newborns. However, there is an ethical issue with taking babies and children off effective therapies, and the best approach will still be prevention. Treating pregnant women with antivirals can prevent 98-99% of infections in newborns.


Baby's feet


In adult patients, the CD4 cells are generally already infected at diagnosis, and lead to re-infection when treatment is stopped, so the approach that worked in the baby would not be appropriate. So, despite the media flurry surrounding this case, while knowing more about the baby’s immune response could potentially lead to new strategies for treatments and perhaps even cures, these are still a very long way off.

There has been one documented case of an HIV cure in an adult –Timothy Brown, also known as the ‘Berlin patient’. He was diagnosed with leukaemia while being treated for HIV, and received a stem cell transplant from a patient with a mutation that leads to immunity to HIV infection, apparently treating both his leukaemia and his HIV.

Suzanne Elvidge is a freelance science, biopharma, business and health writer with more than 20 years of experience. She has written for a range of online and print publications including FierceBiomarkers, FierceDrugDelivery, European Life Science, the Journal of Life Sciences (now the Burrill Report), In Vivo, Life Science Leader, Nature Biotechnology, New Scientist, PR Week and Start-Up. She specialises in writing on pharmaceuticals, biotechnology, healthcare, science, lifestyle and green living, but can write on any topic given enough tea and chocolate biscuits. She lives just beyond the neck end of nowhere in the Peak District with her second-hand bookseller husband and two second-hand cats.