In 2014, the United States instituted a moratorium on gain of function research into influenza, MERS, and SARS.[18] This was in response to the particular risks these airborne pathogens pose. However, many scientists opposed the moratorium, arguing that this limited their ability to develop antiviral therapies.[19] The scientists argued gain of function mutations were necessary, such as adapting MERS to laboratory mice so it could be studied.