Colds and flu are the most common causes of a raised temp-erature in children of all ages - in some cases, up to 105º F (40.6º C). One Baltimore, Maryland, study found that 7 per cent of parents believed temperatures would rise to 110º F (43.3º C) if left untreated, and that one in 15 caregivers thought it could rise to lethal levels in response to an infection. Also, 21 per cent believed that brain damage and other serious consequences could be brought on by a fever of 102º F (38.9º C) or less, while 14 per cent listed death as a potential outcome of fever (Pediatrics, 2001; 107: 1241-6).

However, in most children, the body doesn’t allow fever to spiral out of control (Pediatrics, 2001; 107: 1241-6; Pediatrics, 1992; 90: 846-50). In fact, it’s exceedingly rare for a child’s temperature to exceed 107º F (41.7º C).

Many parents fear that a fever could lead to meningitis or streptococcal sepsis. However, studies have found serious bacterial infection (bacteraemia) in just 1.6-3 per cent of children with temperatures of 102º F (38.9º C) or higher (Pediatrics, 2000; 105: 260-6).

The Baltimore study concluded that parents were in the grip of fever phobia - not surprising considering how many paediatric doctors also share the belief. At a Boston city hospital, 60 per cent of the paediatricians who answered a questionnaire believed that a temperature of 104º F (40º C) or higher could lead to seizures, brain damage or death (Pediatrics, 1992; 90: 851-4).

In fact, a fever is Nature’s defense against infection (Yale J Biol Med, 1986; 59: 89-95), and is often proof of an effective immune system.

Many animal investigations have shown enhanced resistance to infection with increased body temperatures (Ann Intern Med, 1994; 120: 1037-40). A fever can impede the spread of bacteria and viruses, improve survival rates and shorten disease duration in non-life-threatening infections (Microbes Infect, 2000; 2: 1891-904).

An analysis of 218 patients with bacteraemia showed an association between a high temperature on the first day of illness and the likelihood of surviving the condition (Ann Intern Med, 1994; 120: 1037-40).

Indeed, according to the Institute of Noetic Sciences (IONS) database, physicians in the early 1900s noted that, in some cancer patients, remission occurred after the patient developed a fever. In one case, a man with inoperable lung cancer had intermittent fever reaching 103º F (39.4º C) over a number of days. Within six months, his cancer was gone (J Thorac Cardiovasc Surg, 1964; 48: 984-90).

Convulsions Many parents panic when their child has a high fever because of a perceived link between fever and febrile seizures (FS). The abnormal jerking movements of a seizure can, indeed, be a frightening spectacle for parents to endure.

But most seizures (80-85 per cent) are benign and unlikely to lead to serious illness. A benign seizure usually lasts around five minutes or less, and rarely more than 15 minutes. Although they are the most common seizures in children three months to five years of age, they only affect 2-5 per cent of febrile children. They are generally brief and do not require treatment (Clin Pediatr [Phila], 1980; 19: 731-8; Pediatr Neurol, 2004; 2: 9-14; Ann Emerg Med, 2003; 41: 215-22).