The 23rd century contains highly sophisticated and accessible medical facilities and treatments. Most known diseases and viruses have been eliminated through either herd immunity brought on by vaccines or through retroactive treatments and cures. However, in spite of the rigorous preparation Starfleet officers must undergo, any travel presents itself with new environments, new people, and new illnesses. Being the lone Vulcan onboard the Enterprise, Spock’s immune system reacts differently to new illnesses in comparison to his human companions. Due to this it is difficult to tell when he is shrugging off a deadly virus or when he is overdramatizing a simple cold. At the first sign of sniffles, McCoy and M’Benga draw straws.