TABLE 1

Clinical presentation of COVID-19 pneumonia during the first (1 February 2020 to 31 May 2020) and second (1 June 2020 to 1 June 2021) waves

VariablesFirst waveSecond waveWaveReferences
Age (years)61±11.6352±18.6[6, 7, 9, 12, 14, 16, 17, 1922]
[14, 15, 17, 1922]
Gender, male (%)5155[69, 1417, 1922]
[14, 15, 17, 1922]
Symptoms]
 Cough (%)47.240.8[6, 8, 13, 14, 16, 19, 22]
[13, 14, 19, 22]
 Fever (%)46.655[6, 8, 14, 16, 19, 22]
[13, 14, 19, 21, 22]
 Dyspnoea (%)31.733.5[6, 8, 13, 14, 16, 19, 22]
[13, 14, 19, 22]
 Fatigue, asthenia (%)18.227[8, 16]
[22]
 Acute kidney injury (%)10.817[19]
[19]
 Diarrhoea (%)65[6, 8, 14, 16, 19]
[13, 14, 19, 22]
 Vomiting (%)2.75[14, 16, 19]
[14, 19]
 Neurological symptoms (%)0.60.7[14, 16]
[14]
Gas exchange]
PaO2 (mmHg)69.7±21.3665 (56–74)[8, 15]
[15]
PaCO2 (mmHg)34.1±4.732 (28–84)[10, 15]
[15]
PaO2/FIO2 ratio (mmHg)182±65.29249±111[7, 9, 10, 15]
[15]
 Respiratory rate (breaths per min)23±4.828 (22–33)[8, 10, 15]
[15]
 Saturation (%)94±2.7893 (89–97)[8, 15, 18]
[15]

Data expressed as mean±sd or median (interquartile range), unless otherwise stated. PaO2: arterial oxygen tension; PaCO2: arterial carbon dioxide tension; FIO2: inspiratory oxygen fraction.