Possible New Strain of HIV Investigated
Resistance to Treatment and Rapid Progression to AIDS Give Rise to Superbug Fears
Feb. 15, 2005 -- A possible new strain of HIV that is difficult to treat was isolated in a New York City man and is giving rise to the notion that a superbug is on the horizon. But many AIDS experts view the idea with a skeptical eye.
Late last week, officials from the New York City Department of Health and Mental Hygiene announced a middle-aged man was infected with a new and unique strain of HIV -- one that resists most medications used to treat HIV and progresses to full-blown AIDS in a fraction of the usual time.
"Normally you don't see those two things together. Either a strain is drug resistant or it moves quickly, but not both," says HIV investigator Mary Klotman, MD, director of infectious diseases at the Mount Sinai Medical Center in New York City.
"Virtually without exception, highly resistant viruses tend to be less destructive -- they can be destructive, but less destructive. You would not expect them to have a super-virulence," says Fred Valentine, MD, director of the AIDS Center for Research at the NYU School of Medicine.
New HIV Case a Wake-Up Call
In the case of the New York man, the virus has not responded to three of the four types of antiviral drugs used against HIV, and it progressed to AIDS in less than 20 months, just two months after a positive HIV diagnosis was made. Normally, progression from HIV to AIDS in an untreated patient takes 7 to 10 years, with death following months after that time.
The one drug this potential new strain is reported to respond to, Fuzeon, is most effective when used in combination with other antiviral drugs.
In a statement issued last Friday by New York City health officials, Commissioner Thomas R. Freiden, MD, MPH, called the discovery a "wake-up call" that should not be ignored. Indeed, the war on HIV is not only not over, many experts believe the fight has not yet begun.
"I do think it's a wake-up call that public health measures are critical and that prevention is still the best mode of protection. The fact that you even have multi-drug resistant strains of this virus is a clear public health threat, with or without the superbug aspect," says Klotman.
The potentially new strain of HIV is known only as 3-DCR HIV. And New York health officials say it has been identified in only one patient. This initially led some researchers to theorize that the man's individual genetic susceptibility, not the virus itself, may be responsible for its rapid progression.
But this idea came into question on Monday when it was announced that two more cases could be on the horizon.
In New York City, officials announced another man may be harboring a similar strain of the virus, while in California, a San Diego man has tested positive for a similar infection. According to published reports, this man was diagnosed with HIV last fall, around the same time the New York City man was diagnosed, though there is no positive link between the two.
And while experts say more testing is needed to determine if all three viruses are really the same, New York City health officials have issued a nationwide alert for doctors and health departments to retest all patients recently diagnosed with HIV and to look for the new strains.