This was excellent! I’m a bit surprised by the negative reviews, but I’ve also never read a “zombie” book before so perhaps if that’s something you read a lot this might be slow and boring for you. For me, I found it fascinating. It’s got a good balance between the world building and the action, and the focus on the mental health impacts of post-apocalyptic survival is not something that I think gets enough attention. OF COURSE everyone would have trauma and PTSD. What I found really interesting was how that impacted on the plot and the character interactions. It all felt very believable to me. 
I surprised myself a bit that I even wanted to read a book about the aftermath of a pandemic, (albeit a very rapid, destructive, and medically implausible zombie virus) it seems I was ready. Not sure exactly what it was about the blurb for this one that hooked me in, but I’m glad it did. I really enjoyed the quality of the writing and will definitely read more by Whitehead as a result. This one’s a keeper!