Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2018 Mar 29;13(3):e0195135.
doi: 10.1371/journal.pone.0195135. eCollection 2018.

Influenza virus: 16 years' experience of clinical epidemiologic patterns and associated infection factors in hospitalized children in Argentina

Angela Gentile  1 , Maria Florencia Lucion  1 , Maria Del Valle Juarez  1 , Ana Clara Martinez  1 , Viviana Romanin  1 , Julia Bakir  1 , Mariana Viegas  2 , Alicia Mistchenko  2
Affiliations

Influenza virus: 16 years' experience of clinical epidemiologic patterns and associated infection factors in hospitalized children in Argentina

Angela Gentile et al. PLoS One. .

Abstract

Background: Influenza is an important cause of acute lower respiratory tract infection (aLRTI), hospitalization, and mortality in children. This study aimed to describe the clinical and epidemiologic patterns and infection factors associated with influenza, and compare case features of influenza A and B.

Methods: In a prospective, cross-sectional study, patients admitted for aLRTI, between 2000 and 2015, were tested for respiratory syncytial virus, adenovirus, influenza, or parainfluenza, and confirmed by fluorescent antibody (FA) or real-time polymerase chain reaction (RT-PCR) assay of nasopharyngeal aspirates.

Results: Of 14,044 patients, 37.7% (5290) had FA- or RT-PCR-confirmed samples that identified influenza in 2.8% (394/14,044; 91.4% [360] influenza A, 8.6% [34] influenza B) of cases. Influenza frequency followed a seasonal epidemic pattern (May-July, the lowest average temperature months). The median age of cases was 12 months (interquartile range: 6-21 months); 56.1% (221/394) of cases were male. Consolidated pneumonia was the most frequent clinical presentation (56.9%; 224/394). Roughly half (49.7%; 196/394) of all cases had previous respiratory admissions; 9.4% (37/394) were re-admissions; 61.5% (241/392) had comorbidities; 26.2% (102/389) had complications; 7.8% (30/384) had nosocomial infections. The average case fatality rate was 2.1% (8/389). Chronic neurologic disease was significantly higher in influenza B cases compared to influenza A cases (p = 0.030). The independent predictors for influenza were: age ≥6 months, odds ratio (OR): 1.88 (95% confidence interval [CI]: 1.44-2.45); p<0.001; presence of chronic neurologic disease, OR: 1.48 (95% CI: 1.01-2.17); p = 0.041; previous respiratory admissions, OR: 1.71 (95% CI: 1.36-2.14); p<0.001; re-admissions, OR: 1.71 (95% CI: 1.17-2.51); p = 0.006; clinical pneumonia, OR: 1.50 (95% CI: 1.21-1.87); p<0.001; immunodeficiency, OR: 1.87 (95% CI: 1.15-3.05); p = 0.011; cystic fibrosis, OR: 4.42 (95% CI: 1.29-15.14); p = 0.018.

Conclusion: Influenza showed an epidemic seasonal pattern (May-July), with higher risk in children ≥6 months, or with pneumonia, previous respiratory admissions, or certain comorbidities.

PubMed Disclaimer

Conflict of interest statement

Competing Interests: This study did not receive external financing except for editorial assistance, which was provided by Debaditya Das, PhD, and Robert Axford-Gatley, MD, of the GII Secretariat, PAREXEL International, Hackensack, NJ, USA. The GII Secretariat was funded by Sanofi Pasteur Inc., Swiftwater, PA, USA. Sanofi Pasteur did not contribute, review, or edit any content of this manuscript. The authors declare no conflicts of interest. This does not alter our adherence to PLOS ONE policies on sharing data and materials. All authors have made substantial contributions to all of the following: (1) the conception and design of the study: Gentile A, Bakir J; acquisition of data: Lucion MF, Juarez MV, Martinez AC, Romanin V, Viegas M); analysis and interpretation of data: Lucion MF, Juarez MV, Martinez AC, Gentile A; (2) drafting the article or revising it critically for important intellectual content: all authors; (3) final approval of the version to be submitted: all authors.

Figures

Fig 1
Fig 1. Seasonal distribution of confirmed influenza cases in hospitalized children in Buenos Aires, Argentina, 2000–2015 (n = 394).
aMoving average trend line, period = 2.
Fig 2
Fig 2. Annual distribution of confirmed viral pathogens in nasopharyngeal aspirates of hospitalized children in Buenos Aires, Argentina, 2001–2015 (n = 5290).
AV, adenovirus; PIV, parainfluenza virus; RSV, respiratory syncytial virus.
See this image and copyright information in PMC

References

    1. World Health Organization. Influenza (Seasonal). Factsheet No 211. Available from: http://www.who.int/mediacentre/factsheets/fs211/en/
    1. De Kirchner CEF. Abordaje Integral de las Infecciones Respiratorias Agudas: Guia Para el Equipo de Salud. Dirección de Epidemiología-Ministerio de Salud de la Nación. Available from: http://www.msal.gov.ar/cuidados-invierno/abordaje-integral-de-las-infecc...
    1. Arango AE, Jaramillo S, Perez J, Ampuero JS, Espinal D, Donado J, et al. Influenza-like illness sentinel surveillance in one hospital in Medellin, Colombia. 2007–2012. Influenza Other Respir Viruses. 2015;9(1): 1–13. doi: 10.1111/irv.12271 - DOI - PMC - PubMed
    1. McMorrow ML, Emukule GO, Njuguna HN, Bigogo G, Montgomery JM, Nyawanda B, et al. The unrecognized burden of influenza in young Kenyan children, 2008–2012. PLoS One. 2015;10(9): e0138272 doi: 10.1371/journal.pone.0138272 - DOI - PMC - PubMed
    1. Neuzil KM, Mellen BG, Wright PF, Mitchel EF Jr., Griffin MR. The effect of influenza on hospitalizations, outpatient visits, and courses of antibiotics in children. N Engl J Med. 2000;342(4): 225–231. doi: 10.1056/NEJM200001273420401 - DOI - PubMed

MeSH terms