Some antiviral drugs might help viruses become even stronger
A new study raises some serious concerns that antiviral drugs might make viruses emerge even stronger, making them even more resistant to treatment. Researchers from the University of Texas at Austin say antiviral drugs may actually enhance the evolution of viruses by helping them adapt and survive.
The scientists suggest that antiviral drugs that cause nucleic acid to mutate rapidly in order to kill viruses could have the opposite effect.
Jim Bull, Ph.D., a researcher involved in the study from the Institute for Cellular and Molecular Biology at the University of Texas at Austin says, "This work questions whether the practice of 'lethal mutagenesis' of viruses works as predicted. It remains to be seen whether an elevated mutation rate that does not cause rapid viral extinction enhances treatment or may instead thwart treatment by enhancing viral evolution." The study shows antiviral drugs in some instances might do more harm than good for treating flu.
The researchers grew viruses from DNA using an agent that would cause it to mutate. In some cases the virus became weaker or died at predicted. However, a second effect found was that the viruses actually adapted and became even stronger, a process that could occur from forcing viruses to rapidly mutate with the use of antiviral drugs.
Mark Johnston, Editor-in-Chief of the journal GENETICS says, "...the last thing anyone wants to do is make a bad situation worse. More work must be done to determine the actual likelihood of this approach yielding a super virus, knowing that it is possible is a big help in preventing what could be a very big problem."
The findings show that if antiviral drugs given to stop flu spread fail to work as planned, the result could accidentally lead to the development “super viruses”. The researchers suggest a second look at the current practice of using antiviral drugs to stop viruses.
Genetics, Jan 2010; 184: 221 - 232