Virologists in China have published a paper detailing how they created more than 100 hybrid viruses from H5N1 and the H1N1 strain that caused the deadly swine flu pandemic of 2009. The virologists wanted to see if any combinations would transmit between mammals—five did.
The study, published in the journal Science, comes exactly a year after the release of a controversial paper describing how the H5N1 bird flu could theoretically be modified to become human-contagious. At that time, the international community had called for a moratorium on similar research because of threats related to the virus escaping or the information being used for deadly purposes. Various outbreaks of H1N1 have, over the years, proven extremely dangerous. However, researchers argue we need to learn more about how these viruses mutate, and indeed how hybrids form in nature, to better tackle any future outbreaks.
The process by which hybrids form is known as reassortment, and it occurs when an individual is infected with two different strains. Genetic information is exchanged across the two to form a new and unique virus, exactly what happened in 2009 when a combination of different swine, avian, and human flus from across the globe merged. H1N1 in particular seems to reassort more readily and is highly infectious among humans. On the other hand, H5N1 (bird flu) is not typically infectious. The premise behind the study was to see if hybrids could create a more infectious strain of H5N1.