“That HIV is a sneaky little bugger,” my taxi cab driver snickered as he sped away from the Melbourne exposition center last night. “I read about it in the paper. It slips away out of reach and pops back out when it wants to create havoc.” He shook his head back and forth vigorously conveying both awe and disgust. “Man, what a survival instinct!”
It never fails. No matter where you travel around the world. If you want to find the best cheap food, locate non-touristy hot spots, fully grasp the genesis of local political strife or obtain a concise summary of the most significant challenge facing HIV virologists and immunologists to date… talk to a taxi cab driver.
Unfortunately, he’s right. HIV is a sneaky and tenacious virus. Researchers have known for years that during very early infection HIV hides in inactive cells which we now call “latent reservoirs”. When patients are on effective treatment for HIV they are clinically well and have a very low risk of transmitting the virus to others. However, latent reservoirs of infected cells persist and serve as the major obstacle to truly curing HIV infection.
Just last year at the 2013 Conference on Retroviruses and Opportunistic Infections (CROI), a potential game changer in the quest to eradicate latent reservoirs was announced. A baby born to a woman living with HIV in Mississippi who began receiving combination HIV treatment soon after birth was found to have no evidence of HIV infection after discontinuing the drugs months later. The news media labeled this finding as a case of cured HIV infection. The scientific community was a bit more cautious, but hopeful that the “Mississippi baby” was a sign that very early treatment might eradicate or at least diminish latent reservoirs.
A little over one year later, the miracle Mississippi baby is a miracle no more. At yesterday’s session on viral latency, Dr. Deborah Persaud, the immunologist who studied the Mississippi case, confirmed news reports from earlier this month stating that detectable levels of HIV have been noted in the child who is now a toddler and that HIV medication has been resumed.
So, what happened? Was the toddler newly infected through sexual abuse, breast feeding or through some other household contact? No, rigorous studies have ruled these options out. The unfortunate fact is that the toddler’s latent reservoirs returned and were activated or that the sneaky little buggers never left in the first place.
Hopes of a cure via early treatment have been dampened, but not extinguished. Obviously, something went right. The child was off treatment and had no signs of infection for a short period of time. The next step for research scientists is to determine why and to develop a means of achieving a more sustained period of functional cure.
The next step for the rest of us is to remain just as determined as we have been throughout this epidemic. As HIV doggedly persists, so shall we in our efforts to prevent new infections, care for and treat those at risk, affected or infected. Eventually we will prevail because I firmly believe that it is we who have the greatest survival instinct of all.