A young doctor tries an untested vaccine to save her brother’s life which results in a virus that destroys the world as we know it. She now has to lead a group of young survivors to safety. Trying to avoid a world of infected people and scavengers, while being hunted by something they’ve never seen before.

Agreed with Richiev.

I'll add that, the central conflict in the premise is vague. She leads them, they follow, and at some point, they all arrive at the 'safe place' - end of story. What's standing in their way? What's going to make their journey interesting?

It's worth noting that post-apocalypse concepts have been done to death, in many formats and genres, what is it about this particular story that will make it stand out from the rest?

Don't get me wrong, I think that post-apocalypse stories will always have an audience, but I think that such a story needs a unique 'hook' especially now day and age. Said hook may well be the nature or type of conflict they face on their journey.

Unless the person is famous don't use names in the logline.

You should tell us why she is reluctant, I mean she is a doctor, who are usually people who care for those in need, so that kinda throws us off without a quick explanation.

What is her worst nightmare? The plague? Some sort of monster?? Her ex-husband? You should?be specific so we can understand the stakes