Dr. Anthony Fauci once argued that conducting experiments on contagious viruses to increase their potency was worth the risk, even if the work could accidentally lead to a pandemic, it was revealed Friday. The nation’s chief medical advisor wrote in the American Society for Microbiology in October 2012 of the public health benefit to gain-of-function viral experiments — which center on manipulating viruses and making them stronger — as long as there is significant oversight.