Fever and chills: Signs and symptoms

Patient and clinician

A high fever accompanied by chills is an indication or a symptom of influenza infection

High fever with associated chills often present as a symptom of an influenza virus,1,2 so it helps to be able to identify this condition.

Woman breathing vapours

Signs and symptoms

Bacterial infections and viral infections such as the flu can present with fever and chills as associated symptoms.1,2

A fever is part of the body’s defensive response to an active infection.3 The anterior hypothalamus of the brain increases the set-point of core body temperature4 to 38°C or higher, resulting in what we identify as a fever.5

Fever should not be confused with hyperthermia, which occurs when the body produces more heat than it can dissipate.3 Hyperthermia is most commonly the result of wearing excessive clothing that is inappropriate for hot or humid weather, or after heavy physical activity.4

Chills present as rapid muscle contraction and relaxation, seen as shivering. Chills often precede the onset of a fever.2

  • Questions to ask your patient

    Female clinician

    Ask your patient:6

    • What are the main and associated/related symptoms?
    • What are the characteristics of the symptoms?
    • What has been done to treat the fever and chills?
    • Have you had fever and chills before?
    • When did the problem start?
    • What makes the fever/chills better and what makes it worse?
    • Do you have any other medical conditions or take any other medications?
  • When to refer your patient for further care

    Woman coughing

    The patient should immediately be referred to a doctor if any of the following is observed by the pharmacist or reported by the caregiver:

    • Pallor, mottling, ashen or blue colour of the skin, lips, or tongue
    • Failure to respond to social cues
    • Difficulty waking or staying awake
    • Decreased activity
    • Signs of respiratory distress, such as nasal flaring, increased respiratory rate, crackles in chest, grunting, or moderate to severe chest indrawing
    • Fast heart rate
    • Reduced skin turgor
    • Age 3-6 months with a temperature greater than 39°C, or age < 3 months with a temperature greater than 38°C7
    • Fever with a rash
    • Flu-like symptoms that improve but then recur with fever and a worse cough8

Understanding fever and chills

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Find out about the causes of fever and chills.

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Learn how fever and chills should be managed.

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Fever and chills

Find out more about fever and chills by exploring an overview of this condition.

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Patient care resources

Access a leaflet for your patients, which can help them understand the causes of fever and chills and how best to treat them.

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The Panadol Cold & Flu range

Find out how the Panadol Cold & Flu range can help your patients.

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Learning Lab

Find out more in the learning lab

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