Ellie is immune to the virus in The Last One, which was carried by her sister.

The Last One’s protagonist Ellie is immune to the virus that killed everyone else in the world. This was revealed after Ellie’s sister was found dead, but Ellie remained alive and well. Her immunity has been a mystery for fans of The Last One, so here are some possible explanations for why she survived.

Is it because she’s pregnant?

In season one of The Last One, Ellie’s sister Sarah falls ill and dies from a virus. Shortly after Sarah dies, Ellie discovers that she too has contracted the virus. However, instead of dying like her sister did, Ellie recovers from the illness and appears to be fine. This could mean that being pregnant with twins somehow protected her from death by the virus.