A Comparison of Demographic, Epidemiological and Clinical Characteristics of Hospital Influenza-related Viral Pneumonia Patients

Abstract

Objective: Through the comparison of the demographic, epidemiological, and clinical characteristics of hospital human influenza (influenza A (H1N1) pdm09, H3N2, and B) -related and hospitalized avian-origin influenza A (H7N9)-related viral pneumonia patients , find the different between them.Methods: A retrospective study was conducted in hospitalized influenza-related viral pneumonia patients.Results: Human influenza A -related patients in the 35–49-year-old group were more than those with B pneumonia patients (p=0.027), and relatively less in the ≥65-year-old group than B pneumonia patients (p=0.079). The proportion of comorbid condition to human influenza A pneumonia was lower than B pneumonia and H7N9 pneumonia patients (78% vs. 77.8%; p=0.013). The proportion of invasive mechanical ventilation (IMV), lymphocytopenia, elevated lactate dehydrogenase to hospitalized human influenza A-related viral pneumonia patients was higher than B pneumonia patients (p<0.05), but lower than H7N9 pneumonia patients (p<0.05). In the multivariate analysis, pulmonary consolidation (odds ratio (OR): 13.67; 95% confidence interval (CI): 1.54–121.12; p=0.019) and positive bacterial culture (sputum) (OR: 7.71; 95% CI: 2.48–24.03; p<0.001) were independently associated with IMV , while shock (OR: 13.16; 95% CI: 2.06–84.07; p=0.006), white blood cell count >10,000/mm3 (OR: 7.22; 95% CI: 1.47–35.58; p=0.015) and positive bacterial culture(blood or sputum) (OR: 6.27; 95% CI: 1.36–28.85; p=0.018) were independently associated with death in the three types hospitalized influenza-related viral pneumonia patientsConclusions: Hospital influenza B-related viral pneumonia mainly affects the elderly and people with underlying diseases, while human influenza A pneumonia mainly affects the young adults; however, the mortality was similar. The hospitalized human influenza A-related viral pneumonia patients was severer than B pneumonia patients,but milder than H7N9 pneumonia patients. Pulmonary consolidation and positive bacterial culture (sputum) were independently associated with IMV, while shock, white blood cell count >10,000/mm3, and positive bacterial culture (blood or sputum) were independently associated with death to three types hospitalized influenza-related viral pneumonia patients.