What reading level is Infected?

Infected by Sophie Littlefield is at a Level 6-7 reading level (Lexile 920L). Recommended for Middle Grades readers (Ages 9-12).

What age is Infected appropriate for?

Infected is recommended for Ages 9-12. HootRating: 11MP (Moderate — Physical). Content flags: Mild Peril.

What genre is Infected?

Infected is fiction — Dating (Social customs).

Does Infected have any content warnings?

Infected has a HootRating of 11MP (Moderate — Physical). Content flags include: Mild Peril. On HootRated, every book is rated across four dimensions — emotional, physical, social, and thematic — to help parents make informed choices.

How many pages is Infected?

Infected by Sophie Littlefield is 242 pages.

Reviewed by HootRated editorial · Last updated September 7, 2026

Infected

Sophie Littlefield

Infected

Age Rating, Reading Level & Content Guide

by Sophie Littlefield

Reading Level 6-7 11MP Ages 9-12 Balanced Read

The text is written at a 6th grade reading level, the subject matter is intended for middle graders (ages 9–12), and the content has moderate intensity with some emotionally heavy themes.

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About This Book

Carina’s heart races as she wakes up feeling strange and weak. The clock is ticking—she has only thirty-six hours to decode her family’s mysterious puzzles before the deadly drug inside her takes over. With her boyfriend by her side, can they unlock the secrets in time or will everything be lost?

Themes

PuzzlesSurvivalSecretsDatingJuvenile Fiction

Quick Assessment

Infected is a middle-grade thriller about a teenage girl who must solve intricate puzzles tied to her family’s secrets to survive a life-threatening drug. The story involves themes of survival, problem-solving, and young relationships, suitable for ages 9-12. Parents should note the presence of mild peril and tense moments but no graphic content.

Why we rated Infected 11MP

Infected is written at a Level 6-7 reading level with a Lexile measure of 920L across 242 pages. Strong independent readers around grade 7.5 can typically handle this book on their own; with parent or teacher support, Infected works for readers up to grade 8.5.

We rate Infected as 11MP ("Moderate — Physical") because the content sits in the "Moderate" range — moderate conflict that may involve loss, scary scenes, or interpersonal stakes. The strongest signals come from emotional weight, physical peril, thematic difficulty — these are the dimensions parents should evaluate against their reader's tolerance.

Specific content flags noted by reviewers: Mild Peril.

Thematically, Infected explores puzzles, survival, secrets, dating, and juvenile fiction — these threads give the book room to mean different things to different readers.

Good fit for

✓ Children in the Ages 9-12 range — the maturity and attention span match the story's pacing.
✓ Patient readers who enjoy slower, character-driven stories.
✓ Kids drawn to stories about puzzles, survival, secrets.

Maybe not for

! Readers who get easily upset by emotional or moderately dark scenes — the conflict here is real, not just background flavor.
! Reluctant readers who need a fast hook — the pacing here rewards patience.