Dr. Brian Hainline, Chief Medical Officer of the National Collegiate Athletic Association (NCAA), told the Infectious Diseases Society of America (IDSA) on Thursday that the lack of a national testing and contact tracing system has "made it very challenging to make decisions as we approach fall sport." "When we started talking about return to sport in April, we were envisioning that there would be a continued downward trajectory of Covid-19 new infections and deaths -- that there would be a national surveillance system, national testing and national contact tracing -- that would allow us to really navigate this pandemic into re-socializing both in sport and in the rest of society," Hainline said. "And that hasn't happened." "We're moving into very troubled waters right now," the doctor said. "It's a very narrow path to get ball sports right." The Pac-12 and Big Ten -- two of the "Power Five" NCAA conferences -- officially voted to postpone fall sports and continued concerns over student-athletes competing amid a pandemic. But the other major conferences -- the ACC, Big 12, and SEC -- are moving ahead with plans to let them compete in the fall despite the league saying there will be no championships. "We cannot now at this point have fall NCAA championships," NCAA President Mark Emmert said Thursday via Twitter. Emmert mentioned the possibility of using bubble sites -- similar to what the WNBA and NBA are doing now -- in an attempt to keep players safe. Still, he said winter and spring sports have the highest priority, because they lost their championships last March. Assessing the risk The warning didn't just come from the NCAA's top doctor. Two fellows from the IDSA said when it comes to playing sports in the fall, it's all about risk. One said it's safe to assume athletes will get infected with the virus. Dr. Colleen Kraft, Associate Professor of Medicine, Division of Infectious Diseases at Emory University School of Medicine, said that conferences are trying a "dip your toe in and see what happens" approach, while others are not playing at all. For those choosing to play, Kraft predicts Covid-19 cases will pop up. "They will be able to see the experience that many of the others of us have had, where there will be transmission, it will be difficult," she said. Dr. Carlos del Rio, Executive Associate Dean at Emory University School of Medicine at Grady, said we assess risk all the time in our personal lives and that people will have to make decisions based on how much risk they're willing to take. But the numbers in the US, del Rio said, are simply too high at the moment to safely move ahead. "I mean, I feel like the Titanic," del Rio said. "We have hit the iceberg, and we're trying to make decisions on what time should we have the band play." "We need to focus on what's important -- what's important right now is that we need to control this virus," he added. "Not having fall sports this year