How long does fever last with flu
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Duration of Fever in Influenza: Key Insights
Fever Duration in Infants with Nosocomial Influenza
In a study focusing on infants hospitalized during a community outbreak of influenza A, it was found that fever typically lasted an average of 2.7 days. The peak temperatures ranged from 38.2 to 39.8°C. This study highlighted that infants, particularly those with underlying cardiorespiratory conditions, were at a higher risk of developing complications such as lower respiratory tract disease and secondary bacterial pneumonia .
Fever Duration in Children During Influenza Epidemics
Another study examined the natural course of fever in children infected with various strains of the influenza virus (A/H1N1, A/H3N2, and B) during the 2001-2002 epidemic. The findings indicated that fever duration varied with the age of the child and the strain of the virus. Fever was most prominent in younger children and those infected with the A/H3N2 strain. The study also noted that secondary fevers frequently occurred between 72 to 132 hours after the initial fever onset. Overall, the duration of fever was inversely related to the child's age and directly related to the maximum temperature recorded .
Conclusion
In summary, the duration of fever in influenza cases can vary based on age and underlying health conditions. In infants, fever typically lasts around 2.7 days, while in children, the duration can be influenced by the specific influenza strain and the child's age, with younger children experiencing longer fever durations. Understanding these patterns can help in managing and anticipating the course of the illness in different age groups.
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Most relevant research papers on this topic
Nosocomial influenza infection as a cause of intercurrent fevers in infants.
Nosocomial influenza infection is a common cause of intercurrent fevers in infants, with high risk for developing lower respiratory tract disease and prolonged virus shedding.
Natural Course of Fever During Influenza Virus Infection in Children
Fever is most prominent in A/H3N2 and young children during influenza virus infection, with secondary fever common at 72-132 hours, and duration of fever is associated with age and maximal temperature.
Predicting influenza infections during epidemics with use of a clinical case definition.
A clinical case definition including fever (temperature of >38 degrees C) and cough effectively predicted influenza infections during the 1998-1999 flu season, with 86.8% positive predictive value, 39.3% negative predictive value, 77.6% sensitivity, and 55.0% specificity.
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