OBJECTIVES: This study describes the clinical features and course of the patients admitted with COVID-19 illness between the first and second wave of COVID-19 in a tertiary care center in South India.

METHODS: This is a cross sectional study with case record analysis of the patients admitted with moderate and severe COVID -19 illness in a tertiary care centre in South India. Patients admitted between 1^st August 2020 to 30^th November 2020 were considered to be affected in the first wave and those admitted between 30^th April 2021 to 30^th July 2021 were considered to be in the second wave of COVID-19. The symptoms, comorbidities, clinical profile, severity, laboratory parameters, need for assisted ventilation, medications used and outcome were compared between the two-time frames.

RESULTS: A total of 123 patients’ data was analysed in each wave. In Covid first wave, 72 (58%) patients had fever, while 64(52%) patients had fever in Covid second wave. In the first wave 5 (4%) patients had diarrhoea, 4 (3.2%) patients had vomiting. Whereas in second wave, 43 (34%) patients had diarrhoea, 25 (20 percent) patients had vomiting(P<0.001). It was seen in the present study that, more number of patients in the age group of 31 to 40 years had more serious illness and adverse outcomes in second wave compared with patients in first wave where age group of 51-60 years were more seriously affected. In the first wave 31 patients (25%) required non-invasive ventilation(NIV), while 79 patients (64%) required NIV in second wave(P<0.001)

CONCLUSIONS: The patients with COVID-19 illness in the second wave presented with many non-respiratory symptoms like vomiting, diarrhoea, joint pains. The patients who had severe illness in the second were comparatively younger that the patients of the first wave. The requirement of ventilatory support and immunosuppressants were more in the second wave.