Bimodal Effects of Obesity Ratio on Disease Duration of Respiratory Syncytial Virus Infection in Children

Department of Pediatrics, Fuji Chuo Hospital, Shizuoka, Japan.
Allergology International (Impact Factor: 2.46). 03/2011; 60(3):305-8. DOI: 10.2332/allergolint.10-OA-0252
Source: PubMed


Morbid obesity may be associated with hospitalization and possibly death from the 2009 pandemic H1N1 infection, suggesting a yet unknown association between obesity and the severity of viral infections. Thus, we examined association between obesity ratios and duration of disease in children with Respiratory Syncytial Virus (RSV) infection.
A retrospective survey of 243 children admitted for bronchitis, bronchiolitis, pneumonia, and those who tested positive for a RSV test, were observed from a single institute in Japan. Primary outcome was set as the total days of wheezing in both the outpatient clinic and during hospitalization. Secondary outcomes were as follows: 1) total days of fever (37.5°C≤) during hospitalization, and 2) days of drip infusion during hospitalization.
When the obesity ratio was 6 and less, days of wheezing showed significant negative association with obesity ratios. In contrast, when the obesity ratio was more than 6, days of wheezing, days of fever during admission and days of drip infusion showed significant positive association with obesity ratios.
These results suggest that disease duration of RSV infection may be prolonged not only in lean but also in obese children.

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    • "This association between obesity and severity of illness and death from H1N1 influenza has been confirmed by many other reports [10]–[14]. Furthermore, it appears that obesity is a risk factor for severity of illness from other strains of influenza and viral pathogens known to infect the respiratory tract [15], [16]. Importantly, the ability of obesity to diminish host defense against influenza infections has been confirmed in robust and carefully controlled studies using obese mice challenged with the pandemic H1N1 and H3N2 strains of the influenza virus [15], [17], [18]. "
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    PLoS ONE 09/2014; 9(9):e106420. DOI:10.1371/journal.pone.0106420 · 3.23 Impact Factor
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