The HIV virus behaves like Internet malware, spreading through bodies utilizing a two-pronged approach, a new study reveals. Like its electronic equivalent, early treatment is essential in reducing the damage done from an attack, researchers determined.
The human immunodeficiency virus (HIV) spreads through the bloodstream as well as directly between cells. This tactic is similar to the Conficker computer worm that first appeared in 2008 and continues to infect computers to this day. This hybrid spreading by the HIV microorganism is equivalent to the electronic malware exploiting vulnerable networks as well as internal security holes.
Hybrid spreading allows the HIV virus to continue attacking the human immune system until the victim develops acquired immune deficiency syndrome (AIDS).
"The model predicts that cell-to-cell spread becomes increasingly effective as infection progresses and thus may present a considerable treatment barrier," investigators wrote in an article announcing their study.
University College London (UCL) researchers examined white blood cells called CD4+ T cells in 17 patients. These helper cells alert immune systems when foreign microbes invade the body, triggering a response from the body's defensive mechanisms. As HIV proliferates in those infected with the virus, the concentration of CD4+ T cells is reduced, negating the ability of the immune system to respond to the invading microorganisms. Over a period of time, this process could cause an HIV infection to develop into full-blown AIDS.
However, some areas of the body, such as intestines, have concentrations of T cells too high for HIV to destroy local defenses. When the disease-causing microbe encounters one of these regions, the virus switches attack modes, moving from traveling through the bloodstream to attacking neighboring cells directly.
"I was involved in a study looking in general at spreading of worms across the Internet and then I realized the parallel. They have to consistently find another computer to infect outside. They can either look locally in their own networks, their own computers, or you could remotely transmit out a worm to every computer on the Internet. HIV also uses two ways of spreading within the body," Benny Chain of the infection and immunity division at UCL said.
Treatment for HIV infection is often delayed until immune system cells fall below a certain level or the patient becomes ill. This is done to prevent the development of resistance to drugs as well as to reduce the amount of drugs taken by a patient over his or her lifetime. This new study shows early treatment could be most effective at restoring victims to good health.
The model of how HIV can spread like a computer virus was developed to find a way of easily understanding how the disease works by studying a familiar process.
Analysis of how the behavior of HIV infections mimic computer malware attacks was published in the journal PLOS Computational Biology.
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