Thomas is immune to the Flare, the disease that turns people into Cranks, because he and his friends are Munies. The Munies, short for “immune,” possess a rare genetic mutation that protects them from the effects of the Flare. This immunity is what sets them apart from the rest of the population, and it’s the reason why they have been chosen to undergo the Maze and the Scorch trials.
The Flare is a devastating disease that affects the brain, gradually eating away at the minds of those infected. It causes symptoms such as memory loss, hallucinations, and extreme aggression. Eventually, the infected individuals succumb to the disease and become the Cranks, mindless and violent beings that roam the cities, attacking and killing anyone in their path.
Thomas and his friends, however, are fortunate to possess the genetic immunity that shields them from the Flare’s effects. This immunity acts as a sort of protective barrier, preventing the disease from infiltrating their minds and turning them into Cranks. As a result, they retain their sanity and are able to think and reason like normal human beings.
The origins of this immunity are not fully explained in the Maze Runner series, but it is suggested that it is a result of a natural genetic mutation. Just like some people are born with natural immunity to certain diseases, such as chickenpox or measles, the Munies are born with the ability to resist the Flare.
It is worth noting that while Thomas and his friends are immune to the Flare, they are not invincible. They can still be physically harmed, and they are not completely unaffected by the chaos and dangers of the world they live in. However, their immunity gives them a significant advantage and allows them to navigate the trials and challenges they face with a clearer mind and a greater chance of survival.
Thomas is immune to the Flare because he and his friends are Munies, possessing a rare genetic mutation that protects them from the disease’s devastating effects. This immunity sets them apart from the infected population and allows them to retain their sanity and humanity while others succumb to the mindless existence of the Cranks.