Influenza in Malaysian adult patients hospitalized with community-acquired pneumonia, acute exacerbation of chronic obstructive pulmonary disease or asthma: a multicenter, active surveillance study

• Main Authors: Chan, Y.F (Author), Cheong, A. (Author), Chong, Y.M (Author), Doshi, P. (Author), Ismail, A.I (Author), Khor, J. (Author), Lau, J.Z.H (Author), Leong, C.L (Author), Musa, A.N (Author), Ng, K.S (Author), Pang, Y.K (Author), Poh, M.E (Author), Sam, I.-C (Author), Tan, J.L (Author), Taurel, A.-F (Author), Wang, L.P.L (Author), Zim, M.A.M (Author)
• Format: Article
• Language: English
• Published: BioMed Central Ltd 2021
• Series: BMC Infectious Diseases
• Subjects: adult; Adult; Adults; aged; Aged; Article; asthma; Asthma; Child, Preschool; chronic obstructive lung disease; clinical trial; community acquired infection; community acquired pneumonia; Community-Acquired Infections; comorbidity; complication; disease association; disease exacerbation; disease severity; dyspnea; Epidemiology; female; hospitalization; Hospitalization; human; Human; Humans; influenza; Influenza; influenza A (H1N1); influenza A (H3N2); Influenza A virus (H3N2); Influenza A Virus, H3N2 Subtype; Influenza, Human; Influenza-like illness; intensive care unit; Intensive Care Units; major clinical study; Malaysia; Malaysian; male; Male; middle aged; Middle Aged; multicenter study; obstructive lung disease; Outcomes; pneumonia; Pneumonia; preschool child; Pulmonary Disease, Chronic Obstructive; risk factor; young adult
• Online Access: View Fulltext in Publisher; View in Scopus

 Background: Available data on influenza burden across Southeast Asia are largely limited to pediatric populations, with inconsistent findings. Methods: We conducted a multicenter, hospital-based active surveillance study of adults in Malaysia with community-acquired pneumonia (CAP), acute exacerbation of chronic obstructive pulmonary disease (AECOPD) and acute exacerbation of asthma (AEBA), who had influenza-like illness ≤10 days before hospitalization. We estimated the rate of laboratory-confirmed influenza and associated complications over 13 months (July 2018–August 2019) and described the distribution of causative influenza strains. We evaluated predictors of laboratory-confirmed influenza and severe clinical outcomes using multivariate analysis. Results: Of 1106 included patients, 114 (10.3%) were influenza-positive; most were influenza A (85.1%), with A/H1N1pdm09 being the predominant circulating strain during the study following a shift from A/H3N2 from January–February 2019 onwards. In multivariate analyses, an absence of comorbidities (none versus any comorbidity [OR (95%CI), 0.565 (0.329–0.970)], p = 0.038) and of dyspnea (0.544 (0.341–0.868)], p = 0.011) were associated with increased risk of influenza positivity. Overall, 184/1106 (16.6%) patients were admitted to intensive care or high-dependency units (ICU/HDU) (13.2% were influenza positive) and 26/1106 (2.4%) died (2.6% were influenza positive). Males were more likely to have a severe outcome (ICU/HDU admission or death). Conclusions: Influenza was a significant contributor to hospitalizations associated with CAP, AECOPD and AEBA. However, it was not associated with ICU/HDU admission in this population. Study registration, NMRR ID: NMRR-17-889-35,174. © 2021, The Author(s).