Prevalence of respiratory viruses in wheezing children not older than 24 months of age.

INTRODUCTION: Wheezing in children not older than 24 months of age is a frequent event, and viruses are usually the causative agents. The aim of the study was to estimate the prevalence of respiratory viruses in wheezing children who were not older than 24 months of age and who had no history of asthma. METHODS: Fifty-five Mexican children were included in an analytical cross-sectional study. Nasal secretions were obtained by using sterile rayon-tipped applicators to identify the virus by polymerase chain reaction or reverse transcription-polymerase chain reaction: adenovirus, bocavirus, human rhinovirus, influenza virus type A, human metapneumovirus, parainfluenza, rhinovirus, and respiratory syncytial virus. The prevalence of viral etiology was estimated by dividing the frequency of the identified virus by the number of participants. Ninety-five percent confidence intervals for proportions were calculated. RESULTS: Most of the patients were male (35/55, 63.6%). The average time of evolution of wheezing episode was 3 days. The third part of enrolled population were receiving antibiotics. Respiratory viruses were detected in 33 (60%; 95% CI: 46.8-71.9%) out of 55 cases, and viral coinfection was detected in five cases (9.1%; 95% CI: 3.5-19.9%). Human metapneumovirus was the most frequently identified virus (23.6%), followed by bocavirus (14.5%), respiratory syncytial virus and rhinovirus (12.7% each), and to a lesser extent influenza virus type A and parainfluenza. Rhinovirus was the predominant virus in outpatient children (28.6%). In the inpatient emergency room and inhalotherapy room, human metapneumovirus predominated (41.2 and 16.1%, respectively). CONCLUSION: bocavirus and human metapneumovirus were the most frequently identified viruses in Mexican children who were < 2 years of age, suffered from wheezing, and had no history of asthma.

Viral coinfection in acute respiratory infection in Mexican children treated by the emergency service: A cross-sectional study.

BACKGROUND: Acute respiratory infections (ARIs) cause illness. Children under five years of age are highly vulnerable to these infections. Viral coinfection or multiple viral infection is a variable that can have a significant impact on the evolution of these diseases. METHODS: This cross-sectional study was carried out in Mexican children (under five years of age) who had an ARI and who were treated by an emergency service in a hospital in Guadalajara, Jalisco, Mexico. The viral etiology, as well as the presence of multiple viral infections, was determined. A structured questionnaire was used to obtain demographic and clinical information. Odds ratio (OR) was calculated, and univariate and multivariate analyses using logistic regression were performed. RESULTS: In the study population, metapneumovirus (hMPV) was the most frequent virus (22%), followed by adenovirus (hAD) (16%), respiratory syncytial virus (RSV) (14%), rhinovirus (hRV) (12%), bocavirus (hBoV) (9%), influenza virus (IF) (7%), and parainfluenza (PIF) (4%). The frequency of viral coinfections was 31.62%, and multiple logistic regression analysis revealed that hMPV, RSV, PIF, and hBoV were independently associated with multiple viral infection. No difference was found in the clinical manifestation of children with simple and multiple infections. Simple hMPV infection was associated with patients who presented with severe ARI. Using a multivariate analysis, we found that overcrowding is associated with coinfection when the viral etiology was hRV (OR = 2.56, 95% confidence interval (CI) 1.07 to 6.13), IF (OR = 2.56, 95% CI 1.07 to 6.13), PIF (OR = 2.96, 95% CI 1.15 to 7.65), hAD (OR = 2.56, 95% CI 1.07 to 6.13), and hBoV (OR = 2.9, 95% CI 1.14 to 7.34). CONCLUSIONS: Viral coinfections are frequent in children requiring treatment by an emergency service. However, the severity of ARI is similar to that of children with a simple infection. The hMPV is common and may confer a significant disease burden in the Mexican population. Finally, overcrowding is a housing characteristic that favors the development of coinfections.