Initial unsolicited literature report received from healthcare professional on 02 June 2015. Abstract: Background: Seasonal Influenza ("the flu") is a respiratory illness caused by influenza viruses. Yearly influenza vaccination is considered to be protective against illness and/or severity of illness and is recommended by CDC for all individuals greater than 6 months of age. However, the effectiveness of influenza vaccine in older individuals has come under question. Objectives: to describe the clinical characteristics and treatment outcomes of patients admitted to an academic tertiary care hospital with influenza during the 2013-2014 influenza season and determine the impact, if any, of prior influenza vaccination upon patient outcomes. Methods: Medical electronic records were searched for all patients admitted to the hospital with proven influenza during the 2013-2014 influenza season. Cohorts of vaccinated and non-vaccinated patients were then compared to determine the impact of prior influenza vaccination upon respiratory-failure and mortality. Results: Seventy patients met selection criteria. Mean age was 66 years. Sixty-four (91%) patients had at least one underlying co-morbid condition; these conditions included COPD, congestive heart failure, diabetes, and cancer. 60/70 (85%) tested positive for Influenza A, and 43 tested positive for H1N1. Oseltamivir was initiated in 55 (78%) patients. Forty-four percent of the patients had been vaccinated. When separated by vaccination status, those who had been vaccinated had higher rates of ICU admission, need for mechanical or non-invasive ventilation, and mortality. All but mortality reached statistical significance. Conclusion: The data suggest that there was no protective effect from prior vaccination in preventing hospital admission, respiratory failure, and mortality in this population of older men admitted to the hospital with influenza. Among the 31 male patients aged above 50 years, some of the patients having medical history of chronic obstructive pulmonary disease (COPD), congestive heart failure (CHF), diabetes mellitus (DM), comorbidities, Immunocompromised, had received a dose of INFLUENZA VACCINE (batch number, dose and dose number, expiry date, route and site of administration were not reported) on an unspecified date. Concomitant medications were not reported for any of the patient. On an unspecified date, vaccination failure was noted in 31 patients leading to death in 3 patients. 25 patients were found positive for Influenza A, 06 patients were positive for influenza B and influenza A disease was due to H1N1 in 16 patients. It was reported that 31 patients were admitted to the hospital with laboratory proven Influenza between the period of 01 October 2013 to 28 February 2014. 3 patients had a fatal outcome. Of the fatal cases; 2 were immunocompromised; 1 received chemotherapy for metastatic cancer and 1 was on a high-dose steroids. Laboratory investigations included naso-pharyngeal swab testing for influenza rapid antigen and Influenza A reverse transcriptase polymerase chain reaction (RT-PCR) for all who had either negative rapid test results or test positive for flu A. 11 patients were detected with infiltrates on CXR. It was reported that, RT-PCR were positive for H1N1. Other laboratory investigation was unknown. Corrective treatments were TAMIFLU and antibiotics which were received by 24 patients. 12 patients required PPV (positive pressure ventilatory support), 6 patients mechanical ventilation and 7 patients need non-invasive ventilation. At the time of this report, 28 patients were recovered and 03 patients had a fatal outcome. It was not differentiated which 3 patients had Influenza A that died. Documents held by sender: none.