Background: During spring of 2009, pandemic of Influenza A (H1N1) virus emerged and spread globally. We describe the clinical profile of patients who were found H1N1 Positive in Surat district from 27th June 2009 to march 2010.
Methods: Retrospective data of 824 patients from surat districts who were suspected with influenza like illness was collected They were subjected to throat swab testing for H1N1. Out of them 154 were positive for 2009 H1N1 virus with use of real time reverse transcriptase polymerase chain reaction assay. (TAQ MAN real time PCR CDC protocol). Clinical parameters of these 154 patients were analyzed.
Results: Out of 824 suspected H1N1, 154 (18.68%) patients were confirmed (positive) for 2009 HIN1. Maximum (70.77%) patients are in age group 14-50 years. Male [86 (55.84%)] were affected more than Females [68 (44.15%)]. 58 (37.66%) had underlying Co-Morbid condition. Fever (98.70%) and cough (94.15%) were the most common presenting symptom. Total 41 (26.62 %) patients were put on mechanical ventilator, out of them 17 (41.46%) survived. Total 24 (58.53%) patients were initially put on noninvasive (Bipap) ventilator followed by invasive Mechanical ventilator, while 9 (21.95%) patients were put on only noninvasive (Bipap) ventilator and total 8 patients were put directly on invasive Mechanical ventilator. 154 H1N1 positive patients, who underwent chest x-ray on admission 112 (72%) had findings consistent with pneumonia/ARDS. Most common site is lower zone and simultaneous involvement of both lungs is more common than single lung involvement. Out of the 154 patients, those patients who received oseltamivir within 48 hour of onset of illness all were cured. Patients who expired had received oseltamivir after 48 hrs. Our data suggests that the use of oseltamivir was beneficial in hospitalized patients even up to 72 hrs of onset of symptoms. We observed no significant side effect of oseltamivir 150 mg twice day dose for 5-7 days. We observed two peaks of H1N1 during this period, second peak was less severe than first one.
Conclusions: During evaluation period, 2009 H1N1 influenza caused severe illness requiring hospitalization, including pneumonia and respiratory distress and co-morbid condition. Maximum patients were between age group of 14-50 year. Fever and cough were most common presenting symptoms. Nearly 36.36% patients had one or more underlying medical conditions. Mechanical ventilatory support had role in reduction in mortality. Patients seemed to be benefited from antiviral therapy if started within 72 hour of onset of symptom. There were no significant side effects of Oseltamivir observed in this study. Development of ARDS, requirement of Mechanical ventilation and having co-morbid condition were poor prognostic factors. We observed two peaks of H1N1 during this period second peak was less severe than first one. It may be due to development of immunity, Disease awareness, early diagnosis and treatment and health education.