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

Varying degrees of nasopharyngeal (NP) bacterial colonisation are reported in healthy individuals, depending on the age of participants, site of specimen collection and vaccination status [13, 14] . Certain factors increase the risk of nasopharyngeal carriage such as age, geographical area, vaccination status, immunity and socio-economic status [1, [13] [14] [15] . There are limited data from HCWs, and most studies are conducted in children, who generally have higher rates of NP colonisation compared to adults [3, 16] . Commonly isolated organisms are Streptococcus pneumoniae (pneumococcus), Haemophilus influenzae, Moraxella catarrhalis and Staphylococcus aureus [17] . Testing of healthy children showed 50% NP carriage rate for S. aureus [13] , 55-69% for Streptococcus pneumoniae [13, 14, 18] , 67-74%for Moraxella. catarrhalis [13, 14] and 57-83% for Haemophilus influenzae [13, 14, 18] .