Viral and bacterial upper respiratory tract infection in hospital health care workers over time and association with symptoms

Raina MacIntyre, C.; Chughtai, Abrar Ahmad; Zhang, Yi; Seale, Holly; Yang, Peng; Chen, Joshua; Pan, Yang; Zhang, Daitao; Wang, Quanyi

Bacteria were isolated from 170 (76.2%) participants at baseline and 127 (57%) participants at the end of the study (Table 2 ). If co-infections were excluded, bacteria were isolated from 57% participants (128/223) at baseline and 44% (98/223) at end of the study. Overall 196 (88%) participants had bacterial colonisation at start or end of the study -148 participants (66%) had only bacterial colonisation while 48 (22%) participants had co-infection with a virus (Fig. 1a) . Among the total participants, 101 (45.5%) were positive for bacteria at both baseline and end of the study, 68 (30.6%) were positive at baseline and negative at the end, 26 (11.7%) were negative at baseline and positive at the end and 27 (12.2%) were negative at both periods (Fig. 1b) . Among all bacterial positive cases, Streptococcus pneumoniae (isolated or co-infected with Haemophilus influenza) was the most commonly isolated organism at baseline (96%, 163/170) and end of the study (72%, 91/127). Sixty-seven cases were positive for Streptococcus pneumoniae at both baseline and end of the study -18 from respiratory ward (18%, 18/99), 18 from paediatric ward (38%, 18/47), 9 from fever clinics (29%, 9/31) and 22 from emergency ward (48%, 22/46).