An ER doctor says kids are coming into the hospital with terrifying hallucinations — and warns it's a classic flu symptom

• A mom and ER doctor says her 7-year-old daughter recently started hallucinating and hearing voices.
• The pediatrician didn't panic, because she recognized her daughter's distress as a classic sign of infection.
• Fevers, our body's attempt to fight viruses like the flu, can prompt brief periods of delirium.

One recent morning at 7 a.m., Kathryn MacKinlay realized her sick daughter Marissa was hallucinating.

"Mommy, Mommy, make it stop!" Marissa said. She described hearing people shouting unbearably.

MacKinlay tried to soothe her 7-year-old's fears: "Sweetie, no one is yelling."

The pediatrician was able to remain calm because she knew exactly what was happening to her daughter. Marissa was sick, with other flu-like symptoms. The hallucinations her little one was experiencing were the exact same kind of brief delirium that has filled up her hospital in recent weeks. It's a signal of the body's fight against a common, invading virus.

"As an emergency doctor , I have seen many other kids hallucinating these last few weeks," MacKinlay said in a recent blog post . "These young patients have all been influenza positive ."

Why hallucinations can be a hallmark of the flu

In the Canadian hospital where MacKinlay works, she said many sick children have recently been complaining of:

• hearing loud sounds
• seeing objects as too large or too far away
• and feeling scared that someone or something is trying to hurt them

These are all classic signs of the delirium that can come along with the fevers our body uses to fight against infection.

Our brains are sensitive to temperature changes, so fevers can lead to hallucinations by disrupting normal activity. The episodes are generally brief, lasting just a few minutes, and do not require medical attention.

If a child's fever is higher than 104 degrees Fahrenheit , does not respond to treatment like Advil (ibuprofen) or Tylenol (acetaminophen), or if a patient is experiencing prolonged episodes of confusion (for more than a few minutes), it's time to seek help.

But in most cases, "your little one will be okay," MacKinlay said. Simply "offer cuddles" and wait for the feverish confusion to pass. The doctor recommends "alternating Advil and Tylenol every three hours" to bring the patient's fever down, which should, in turn, alleviate delirium episodes.

The mom and ER doctor is now happy to report that "we are back to playing in the snow and hearing no voices other than the shrieks of laughter of healthy kids."