Clinical profile and outcome of patients admitted with swine-origin Influenza A H1N1 virus infection at a tertiary care hospital in Western India

Background: Most of the studies on swine flu H1N1 have been done during the pandemic phase. There was a sudden upsurge in virus activity in 2015 at many centers in India. The present study was designed to assess the current status and pattern of H1N1 infection. The primary objective of this study is to study the clinical profile of patients admitted with Swine-origin influenza A (H1N1) virus infection and Secondary objective is to study the clinical outcome in terms of morbidity and mortality.Methods: This was a retrospective observational study done at a tertiary care centre from March 2015 to April 2016. All admitted and confirmed cases of H1N1 swine flu infection were studied for demographic details, co-existing medical conditions and clinical presentation. Data regarding the course of disease, complications, treatments and outcomes were recorded from the clinical record.Results: Common presenting symptoms were cough and fever (95%). Common findings were fever (62.5%), tachycardia, tachypnea and crepitation on auscultation (58.5%). Associated comorbidities were Diabetes mellitus (19.5%), Chronic kidney disease (17%), immunosuppression (9.8%). Consolidation was seen in nearly half of the patients on radiological imaging. Complications noted in our patients were pneumonia (45%), respiratory failure (31%) and ARDS (14.6%). Seventeen percent of patients required non-invasive and invasive mechanical ventilation. Around 25 percent of cases, required ICU admission while two patients died during the hospital stay.Conclusions: The study emphasizes and restates the morbidities caused by H1N1 swine influenza infection as nearly half of the patients in this study experienced severe illness and complications.