Dr John Crimmins explores the challenges of assessing children with feverish illness and discusses recent guidance updates on drug treatment and management


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Key learning points: NICE fever in under 5s

Between 20% and 40% of parents report feverish illness in young children each year, and fever is therefore probably the commonest reason for a child to be taken to the doctor. Feverish illness is also the second most common reason for a child being admitted to hospital. Despite advances in healthcare, infections remain the leading cause of death in children under the age of 5 years.1

Assessing young children with raised temperatures is an everyday occurrence in general practice and is usually dealt with effectively and efficiently by GPs. However, children who have been seen and assessed can still present later with serious bacterial infection (SBI) and, in a few tragic cases, die or sustain permanent physical damage. A significant number of children have no obvious cause of fever despite careful assessment, and are of particular concern because it is especially difficult to distinguish between simple viral illnesses and life-threatening bacterial infections in this group.1

Changing patterns of healthcare also now mean that the initial assessment of febrile children may occur in settings outside of general practice, for example, via telephone consultation, a variety of out-of-hours settings, or A&E departments.1 The relevant experience of doctors and nurses working in these settings may vary enormously, and so a standard approach is needed for the effective recognition, assessment, and treatment of feverish illnesses in children in any setting.

NICE guideline update on feverish illness in children

Box 1: NICE Accreditation Mark
NICE accreditation mark

NICE Clinical Guideline 160 on Feverish illness in children: Assessment and initial management in children younger than 5 years has been awarded the NICE Accreditation Mark.

This Mark identifies the most robustly produced guidance available.
See evidence.nhs.uk/accreditation for further details.


NICE Clinical Guideline (CG) 160 on Feverish illness in children: assessment and initial management in children younger than 5 years (see www.nice.org.uk/guidance/CG160),1 was published in May 2013, replacing and updating the 2007 guidance, NICE CG47, on feverish illness in children.

NICE CG47 (now superseded by NICE CG160) was produced to help healthcare professionals make the assessment of febrile children as effective as possible, as well as to advise on evidence-based management. The guideline also aimed to ensure that the initial assessment criteria were the same wherever the consultation occurred.

Scope of the guideline

The scope of CG1601 is the management of children up to the age of 5 years with a fever without apparent cause. The vast majority of these children will have a short-term, self-limiting viral infection, but a few will be in the early stages of a serious, potentially life-threatening bacterial infection.

Identifying children most at risk

Before publication of the 2007 guideline, many attempts had been made to clarify how children most at risk could be identified, but no generally acceptable or effective measure was available. The guideline development group searched all available and relevant evidence regarding early identification of the at-risk group, as well as existing assessment tools such as the Yale Observation Score system.2

Methods of measuring temperature were extensively researched, as the readings obtained by different measuring devices can vary significantly. The most reliable and acceptable technique is to use an electronic aural or axillary thermometer to measure the temperature, and the guidance is based on using this method.1 Other methods of measuring temperature are available, but there is insufficient evidence of accuracy and consistency to recommend them for routine assessment. Measuring rectal temperature, although accurate, was thought to be too invasive for routine assessment when other less traumatic means of measuring core temperature
are available.

The guideline development process showed that no single objective parameter is of paramount value in the assessment of a febrile child; for example, the height of the fever generally is not a reliable indicator of the severity of the illness. The evidence did however support more subjective concerns, and suggested that both parental concern and a child ‘appearing unwell’ to the examining doctor were associated with
a greater risk of an underlying SBI. A large number of such objective and subjective parameters have been tested in clinical trials, with a large variation in effectiveness at suggesting either increased or decreased risk.3

The traffic light system—update

The traffic light system was developed from the wealth of clinical evidence gathered for the 2007 guideline, as a means of assessing risk in children with fever. The update for the 2013 guideline1 examined, in particular, new clinical evidence in the hope of refining the traffic light system.4

The traffic light system is probably now familiar to GPs (see Table 1).1 Features of the feverish child at the time of examination are divided into three columns (red, amber, or green), where symptoms and signs in the:

  • green column suggest that the risk of SBI is low
  • amber column indicate ‘caution’ (i.e. that all is not well), but one amber feature is not in itself an effective indicator of serious infection
  • red column denote children who are unwell, at high risk of SBI, and in need of specialist care.

Children with fever and any of the symptoms or signs in the red column should be recognised as being at high risk. Similarly, children with fever and any of the symptoms or signs in the amber column, and none in the red column, should be recognised as being at intermediate risk. Children with symptoms and signs in the green column, and none in the amber or red columns, are at low risk.1

From a general practice point of view, some reassurance can be taken from the traffic light approach. It is reassuring to know that a practitioner’s instinctive impressions of a child with a fever are likely to be correct: a child with a fever who appears otherwise well (showing the features in the green list) is very unlikely to be developing a serious infection, whereas the significantly unwell child (showing any of the symptoms or signs on the red list) is at risk and should be referred for urgent acute paediatric unit management.

The amber column is the difficult area and contains indicators ranging from strictly observational (e.g. pallor reported by parent/carer), to investigative (e.g. oxygen saturation less than 95% on room air). An important update in the 2013 version of the guideline1 is the specific inclusion of tachycardia and the heart rate at different ages, both of which cause concern. Heart rate changes with age and with fluctuations in body temperature, but recently available data4 have allowed inclusion of specific levels. The Advanced Paediatric Life Support criteria define tachycardia, by age of the child and heart beats per minute (bpm), as:5

  • age <12 months: >160 bpm
  • age 12–24 months: >150 bpm
  • age 2–5 years: >140 bpm.

The general advice is that a child showing two or more amber features may warrant referral for further assessment/investigation, but this needs to be interpreted within the context of the overall assessment; one child with a single but severe amber symptom or sign may require immediate specialist care, while another child with two or more mild features may be best cared for at home.

The specific advice in using the guideline,1 including the traffic light system, is that co-existing medical conditions must be taken into account. Certain specific areas of concern are that:

  • assessing activity criteria in children with brain injury or neurodegenerative disease may be difficult (largely depending on their usual activity levels)
  • respiratory criteria may be different in children with chronic lung disease, and congenital heart disease may influence the cardiovascular assessment.

In such situations, a change from the child’s normal state is the important factor.

A child aged younger than 3 months old with a temperature of 38°C or higher is a ‘red’ sign, while a child aged 3 to 6 months with a temperature of 39°C or higher is a cause for concern, but at the ‘amber’ level.1

The traffic light system is therefore intended as a framework for assessing a child with fever, and should be used in addition to, or alongside, a full history and examination. The hope is that it may help practitioners, not to refer more children to paediatric specialist care, but to make referrals as appropriately as possible.

Table 1: Traffic light system for identifying risk of serious illness*1
 Green—low riskAmber­—intermediate riskRed—high risk
Colour (of skin, lips or tongue
  • normal colour
  • pallor reported by parent/carer
  • pale/mottled/ashen/blue
  • responds normally to social cues
  • content/smiles
  • stays awake or awakens quickly
  • strong normal cry/not crying
  • not responding normally to social cues
  • no smile
  • wakes only with prolonged stimulation
  • decreased activity
  • no response to social cues
  • appears ill to a healthcare professional
  • does not wake or if roused does not stay awake
  • weak, high-pitched or continuous cry
  • nasal flaring
    • tachypnoea:
    • RR >50 breaths/minute,
      age 6–12 months;
    • RR >40 breaths/minute,
      age >12 months
  • oxygen saturation ?95%
    in air
  • crackles in the chest
  • grunting
  • tachypnoea: RR >60 breaths/minute
  • moderate or severe chest indrawing
Circulation and hydration
  • normal skin and eyes
  • moist mucous membranes
  • tachycardia:
    • >160 beats/minute,
      age <12 months
    • >150 beats/minute,
      age 12–24 months
    • >140 beats/minute,
      age 2–5 years
    • CRT ?3 seconds
  • dry mucous membranes
  • poor feeding in infants
  • reduced urine output
  • reduced skin turgor
  • none of the amber or red symptoms or signs
  • age 3–6 months, temperature ?39°C
  • fever for ?5 days
  • rigors
  • swelling of a limb or joint
  • non-weight bearing limb/ not using an extremity
  • age <3 months,
    temperature ?38°C
  • non-blanching rash
  • bulging fontanelle
  • neck stiffness
  • status epilepticus
  • focal neurological signs
  • focal seizures
CRT=capillary refill time; RR=respiratory rate

* This traffic light table should be used in conjunction with the recommendations in the guideline on investigations in children with fever.
See www.nice.org.uk/guidance/CG160 (update of NICE clinical guideline 47).

Reproduced with kind permission from NICE

Safety net

The guideline1 is specific in recognising that the initial consultation is an assessment of the current position in a dynamic process. It is essential that a formal safety net be provided for parents and carers. Such safety-netting involves an explanation of the expected course of the febrile illness, and instructions as to changes in the child’s condition that would make a further assessment advisable. Specific indications of serious change include:1

  • a fit
  • a non-blanching rash
  • general deterioration
  • fever >5 days
  • increased parental concern or fear that they are unable to care for the child.

In addition, parents/carers should be advised on how to access further care should any of the eventualities occur, and/or follow up or direct access to other healthcare providers (including out of hours) should be arranged.1


In addition to producing advice on assessing febrile children, the guideline development group also studied the aims and means of treating the actual fever. Several important points emerged from (or were clarified by) the evidence searches:4

  • treating fever with physical means, such as subjecting the child to low temperatures or cool bathing, has little effect and may cause distress. An appropriate environment to encourage normal physiological means of temperature regulation is required
  • treating the fever with antipyretic agents does not prevent febrile convulsions
  • there is some evidence that the actual fever is a useful physiological response to infection and that reducing the fever pharmacologically may prolong the disease, although there is no convincing evidence that disease severity is affected
  • both paracetamol and ibuprofen are effective at reducing temperature as well as relieving associated symptoms. The aim of using these drugs should be relief of distress rather than attaining a normal body temperature
  • while there is a small risk of side-effects from either paracetamol or ibuprofen, this risk is small and either agent can be used within normal dosage parameters. There is no evidence of harmful interaction between the two drugs
  • there is some evidence that combined use of paracetamol and ibuprofen can result in a reduction in body temperature greater than if a single agent is used. This additional effect is small and cannot be extrapolated to bringing greater relief of distress. The advice therefore is to use either drug initially, and only to alternate with the second agent if the aim of relieving distress has not been achieved
  • there is currently insufficient clinical evidence to determine whether a response (or lack of response) to antipyretic agents is an indicator of the severity of the underlying disease, so this should not in itself be used as a determining factor in the consultation
  • there is also insufficient evidence regarding the effect of antipyretic agents on individual determinants included in the traffic light table. It is not possible to specify whether a febrile child who is generally well, but feeding poorly and/or not responding normally to social cues before an antipyretic, who brightens up and starts feeding after this treatment, should be regarded as a ‘green-column’ child, or whether they should be placed in the amber section. While the child’s response in this situation is instinctively encouraging, it is not clear from available evidence that it should be.

Conclusion and implications for primary care

The death of a child from a potentially treatable condition is a tragedy for all concerned. It is clear that the earlier the diagnosis of an SBI is made, and treatment initiated, the better the prognosis. There can be few events more distressing in a medical career than the acute deterioration and death of a child who has been previously assessed as having a minor illness.

While my involvement in the development of NICE CG160 on feverish illness in children has not radically changed my mode of assessing children, I have made some specific adjustments, particularly with regard to measuring and recording objective parameters, such as temperature, heart rate, and respiratory rate. I commend the key points based on the updated guideline to all healthcare practitioners.

NICE implementation tools

NICE has developed the following tools to support implementation of Clinical Guideline 160 (CG160) on Feverish illness in children: Assessment and initial management in children younger than 5 years. The tools are now available to download from the NICE website.

NICE support for service improvement systems and audit

Baseline assessment toolaudit.jpg

The baseline assessment is an Excel spreadsheet that can be used by organisations to identify if they are in line with practice recommended in NICE guidance, and to help them plan activity that will help them meet the recommendations.

NICE support for commissioners

Costing statementCommissioning

A costing statement has been produced because of wide variation in practice, therefore a national resource impact would be challenging to estimate. The statement has been prepared in consultation with experts working in this area and has been approved for publication by NICE.

Key to NICE implementation icons

Commissioning.epsNICE support for commissioners

  • Support package for commissioners and others for quality standards
  • NICE guide for commissioners
  • NICE cost impact support for guidance (selection from national report/local template/costing statement, dependent on topic)

Audit.epsNICE support for service improvement systems and audit

  • Forward planner
  • 'How to' guides (generic advice on processes)
  • Local government briefings (with Centre for Public Health Excellence)
  • Baseline assessment tool for guidance
  • Audit support including electronic data collection tools
  • E-learning modules (commissioned)

Education.epsNICE support for education and learning

  • Clinical case scenarios
  • Learning packages including slide sets
  • Podcasts
  • Shared learning and other local best practice examples
  1. NICE. Feverish illness in children: assessment and initial management in children younger than 5 years. Clinical Guideline 160. London: NICE, 2013. Available at: www.nice.org.uk/cg160nhs_accreditation
  2. McCarthy P, Sharpe M, Spiesel S et al. Observation scales to identify serious illness in febrile children. Pediatrics 1982; 70 (5): 802–809.
  3. National Collaborating Centre for Women’s and Children’s Health. Feverish illness in children—assessment and initial management in children younger than 5 years. London: Royal College of Obstetricians and Gynaecologists, 2007. Available at: www.nice.org.uk/nicemedia/pdf/CG47Guidance.pdfnhs_accreditation
  4. National Collaborating Centre for Women’s and Children’s Health. Feverish illness in children: assessment and initial management in children younger than 5 years. 2nd edn. London: Royal College of Obstetricians and Gynaecologists, 2013.
  5. Advanced Life Support Group. Advanced paediatric life support: the practical approach. 4th edn. Chichester: Wiley-Blackwell, 2005. G