Researchers have created a new model detailing HIV progression and showed that the disease spreads much like computer worms or malwares, predicting that early treatment is integral to beating AIDS.
HIV spreads around the body either through the blood stream or between cells directly. When specialists on the disease and experts on network security from the University College London saw this, they teamed up to come up with a model on hybrid spreading. Sample data collected from 17 HIV patients helped in completing the model, which also accurately predicted progression from HIV to AIDS in patients part of a major clinical trial.
CD4+ T-cells play an important role within the immune system by protecting against diseases. HIV infects these cells, reducing their number as the disease progresses. At the point that the immune system is no longer able to function properly, AIDS takes place.
Current guidelines set in place by the World Health Organization recommend that HIV treatment only begins when T-cells reach a certain level after an infection. However, the model the researchers created predicted that treatment should begin as soon as an infection is detected to prevent AIDS from fully taking hold.
Benny Chain, co-senior author for the study, explained that HIV cells found in the bloodstream are always in relatively low numbers so an infection that spreads just through the bloodstream is not enough to lead to AIDS. He added that it is likely that only after gaining a foothold in a certain part of the body does HIV turn to cell-to-cell transfer to more effectively spread the virus.
If treatment begins after HIV has already spread to an area with a lot of T-cells, preventing further infection via the bloodstream will not be effective in curbing AIDS. Instead, blocking cell-to-cell transfers will work better in preventing HIV progression, as suggested by the model. This also highlighted the need for new kinds of treatment.
The model created took inspiration from similarities between the HIV virus and computer worms like the ‘Conflicker' which took down police and military computer networks all over Europe. The two both rely on hybrid spreading to progress, persist for very long periods of time and are extremely difficult to get rid of.
"Our model enables us to explain these important properties and to predict the infection process," said Changwang Zhang, lead author for the study.
The study was published in the journal PLOS Computational Biology. Other authors include: Clare Jolly, Persephone Borrow, Ian Williams, Pierre Pellegrino, Elisabetta Groppelli and Shi Zhou.
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