A5V4d

Other
Fever for 5 days or more (included in 2007 traffic light table)
Clinical assessment of the child with fever
This sign was included in the 2007 guideline as it was indicative of Kawasaki disease; however, the
new review found only two studies that reported on Kawasaki disease, neither of which reported on
duration of fever. There was evidence that those with a serious bacterial illness had had fever for
longer than children without serious illness (significant P values), and children who had had fever for
three days or more were significantly more likely to have a urinary tract infection than those who had
not (significant relative risk). No evidence was reported that examined fever duration of longer than 5
days.
Based on their clinical experience, the GDG members argued that most non-serious illnesses will
resolve themselves after 5 days, and therefore a fever of more than 5 days duration is a good
indicator of serious illness. The GDG acknowledged that in the evidence there is a weak correlation
between duration of fever and severity of illness. However, it believed this may be in part to relying on
parental/caregiver recall of when the fever started. Also, the evidence was limited as many studies
excluded children who had had fever for 5 days or longer and none of the studies used 5 days as a
cut-off.
The GDG concluded that the evidence in the current review was not strong enough to change the
2007 recommendations and therefore no such changes were made.
Temperature of 38°C or more in children age under 3 months, temperature of 39°C or more
in children age 3–6 months (included in 2007 traffic light table)
In the 2007 guideline the GDG concluded that healthcare professionals should be aware that there is
an association between height of body temperature and risk of serious bacterial illness. However, this
association was not sufficiently robust to recommend immediate action or referral based on body
temperature alone. An exception was made for children aged less than 6 months with a body
temperature of 39°C or higher because the evidence was strongest for this age group.
In the 2013 review, the GDG acknowledged the ambiguity of the age groups in the 2007
recommendation regarding height of fever, and altered the text of the recommendation to reflect the
intended meaning of less than 3 months for one group, and age 3 to 6 months (inclusive) for the other
group. No studies were identified for the 3 to 6 month age group specifically, although most studies
included this age group in their sample. The studies often did not report how the temperature was
measured, and the studies tended to look at one or two cut-offs rather than a range of temperatures,
making it hard to compare data from different temperature cut-offs. Despite these limitations in the
data, the GDG highlighted that there is a correlation between high temperature and serious bacterial
infection in general, but that, on an individual basis, high temperature was not useful for detecting
serious illness. The current review suggests that there is a plateau in positive predictive values,
negative predictive values and likelihood ratios around 39°C and 40°C, suggesting that a temperature
above this does not provide a better indication of serious illness. The GDG therefore decided to move
the recommendation regarding height of fever in the 3 to 6 month age group from the red column to
the amber column. The GDG acknowledged that any fever in a child under 3 months is a risk factor
for serious illness in itself, and so the recommendation for this age group remained in the red column.
The GDG made it clear that use of height of fever alone should not be used to diagnosis a serious
illness. In addition, the GDG noted that children aged less than 3 months with fever are generally at a
higher risk of serious illness (see Section 8.2). The incidence of serious illness in this group, for
instance, was over ten times higher than that in older children. The clinical studies that provide the
evidence for this age group used a body temperature of 38°C or higher as the definition of fever.
The GDG was also aware that infants in England and Wales have their first immunisations at age 2
months and that most of these infants experience post-immunisation fever. There was a discussion
about what impact a recommendation on height of fever in this age group would have on health
services, with a potential for health services to be overwhelmed. However, it was highlighted that
parents and carers were routinely advised to expect their child to have a fever within 48 hours of
immunisation and that there was no evidence of an increase in consultations due to this.
The GDG therefore decided that children aged less than 3 months with a body temperature of 38°C or
higher should be included in the recommendation about risk of serious illness.
105
2013 Update