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Clinical features of influenza C virus infection in children
Yoko Matsuzaki1, Noriko Katsushima, Yukio Nagai
1Department of Infectious Diseases, Yamagata University School of Medicine, Iida-Nishi, Yamagata, Japan. matuzaki@med.id.yamagata-u.ac.jp
Insights
Influenza C virus commonly causes upper respiratory illness in young children. Infants under two years old face a higher risk of severe complications, including lower respiratory tract infections like pneumonia.
Area of Science:
- Pediatric Infectious Diseases
- Virology
- Respiratory Illness
Background:
- Influenza C virus is globally prevalent but poorly understood due to isolation challenges.
- Limited clinical data exists for influenza C virus infections.
Purpose of the Study:
- To investigate the clinical features of influenza C virus infection in children.
- To identify risk factors for severe outcomes.
Main Methods:
- Analysis of clinical data from 170 children infected with influenza C virus.
- Specimens collected from pediatric patients aged 15 years or younger between 1990 and 2004.
Main Results:
- Most infections (92.4%) occurred in children under 6 years old.
- Common symptoms included fever (90.0%), cough (74.1%), and rhinorrhea (61.8%).
- Hospitalization rates were higher in children under 2 years old (30.4%) compared to those aged 2-5 (11.9%), with lower respiratory tract illness being common.
Conclusions:
- Influenza C virus is a significant cause of upper respiratory tract illness in children under 6.
- Infants under 2 years old have a heightened risk of lower respiratory tract complications.
Background:
Seroepidemiological studies have revealed that influenza C virus is widely distributed globally. However, because the isolation of this virus is difficult, there have been few reports on its clinical features.
Methods:
Between December 1990 and November 2004, 84,946 respiratory-tract specimens were obtained from patients < or = 15 years old. On the basis of the results of isolation of virus, we examined the clinical data on children infected with influenza C virus.
Results:
Of 170 children infected with influenza C virus, 157 (92.4%) were < 6 years old. Fever (frequency, 90.0%), cough (frequency, 74.1%), and rhinorrhea (frequency, 61.8%) were the most frequent symptoms. The mean duration of fever was 2.88 days (standard deviation, 1.66 days). Of the 170 children, 29 were hospitalized, and 21 (72.4%) of these 29 had lower-respiratory-tract illness such as pneumonia, bronchitis, and bronchiolitis. The rate of hospital admission was significantly higher in children < 2 years old than in children 2-5 years old (30.4% vs. 11.9%; P = .0043).
Conclusions:
Influenza C virus is a significant cause of upper-respiratory-tract illness in children < 6 years old, and the risk of complications with lower-respiratory-tract illness is particularly high in children < 2 years old.
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Acute Pharyngitis
Acute pharyngitis is the inflammation of the back of the throat (pharynx), commonly resulting in a sore throat. It is a frequently encountered condition that prompts individuals to seek medical advice.
Classification
Acute pharyngitis can be categorized based on its underlying cause:
