The second American case of the MERS virus has been reported in Florida, according to NBC News. The case seems to be unrelated to the first US case of the virus, which struck a health-care worker in Munster, Indiana, but has many officials concerned about MERS potential to spread globally. MERS was first identified in 2012, but this March saw a surge in cases for reasons that remain unclear. Its a respiratory virus, in the same family as SARS, with a five-day incubation period that many worry could aid the viruss spread.