It is well known that hospital pathogens can be transmitted from the hands of health care workers (HCWs) to patients.1 This may occur through direct contact with the patient or indirectly, via an inanimate object. Many articles of clothing and equipment, such as neckties,2-9 doctors’ coats,10-12 stethoscopes13-17 and pens,18,19 have been noted to carry potential pathogens.

Items such as the ends of neckties have been suggested as potential sources of nosocomial infection because of their position at waist level, their tendency to swing freely as the wearer leans forward and the fact that many are not machine-washable. Most are capable of being colonised with bacteria, including pathogens such as methicillin-resistant Staphylococcus aureus (MRSA).4,20 Similarly, plastic identity badges attached to fabric lanyards hang around the front of the body, where, because of their pendulous nature, they can come into contact with patients and may act as a source of infection (Box 1).

A literature review did not reveal any published investigations of bacterial colonisation of identity badges and lanyards worn by HCWs. The objective of our study was to determine the level and type of contamination that may be present on these items. We also examined the relative risk of pathogen carriage between nurses and doctors and documented clinical bacterial isolates from selected wards during the study period.

Identity badges and lanyards worn by HCWs frequently come into contact with patients and the clinical environment, and it is reasonable to expect that they could become colonised with nosocomial pathogens. To our knowledge, our study — in which pathogenic bacteria such as MRSA, MSSA, Enterococcus spp and GNB were recovered from both lanyards and identity badges — is the first to demonstrate that contamination of such accessories is possible. Furthermore, we showed that lanyards were particularly contaminated, carrying a median bacterial load 10 times greater, per unit of surface area, than identity badges.

Previous studies have documented that potential pathogens can be recovered from many articles of clothing worn by HCWs. The organisms identified have mainly been skin commensals (including MSSA), but two studies have detected MRSA on doctors’ neckties4,9 and another detected MRSA on the membranes of physicians’ stethoscopes.16

Bacterial contamination of HCWs’ clothing and equipment may often come indirectly from the hospital environment rather than from infected patients.21 Contaminated clothing or equipment provides a reservoir from which HCWs may reinoculate their hands, even after hand hygiene procedures have been performed, thus allowing transmission of pathogens to patients or the environment. The British Medical Association (BMA) has suggested that doctors refrain from wearing non-essential items of clothing, such as ties, as they have the potential to act as a vector for the transmission of infections.22 However, the evidence supporting the BMA recommendation is limited. Although potential pathogens such as S. aureus have been isolated from doctors’ neckties,20 in most studies only a small number of ties were tested.

Lanyards and identity badges are worn by both male and female clinical staff for long periods of time without cleaning. Their position at waist level and their pendulous nature increase the risk that they will become contaminated. Studies have shown that bacteria survive for long periods on hospital fabrics and plastic surfaces, with gram-negative bacteria surviving for over 60 days and enterococci and staphylococci for over 90 days.23,24 Patients with MSSA, MRSA, Enterococcus spp and GNB infections were present in all three wards included in our study, and these typical hospital pathogens were recovered from identity badges and lanyards.

Our study showed that doctors are four times more likely than nurses to carry MSSA on their lanyards. A recent observational study by Pittet et al25 showed that compliance with hand hygiene protocols is low among doctors compared with nurses, and this may help to explain the greater contamination of doctors’ lanyards with hospital pathogens in our study. However, further larger studies are required to compare the carriage rate of potential pathogens by doctors and nurses.

One limitation of our study is that we did not assess HCWs for carriage of S. aureus in the nares or on the hands, and so could not correlate this with S. aureus isolated from the lanyard set. Although HCWs estimated how long they had used the lanyards, we were unable to establish at what point they became contaminated with pathogens. The literature suggests that a steady state of maximum contamination is reached quickly and does not significantly change thereafter.10 A prospective study to determine the timing of acquisition and duration of bacterial contamination in a clinical setting may be useful.

Lanyards are the most common means of carrying identity badges as well as a variety of non-essential items. Based on our observations, we suggest that two useful infection control precautions may be to remove non-essential connections and to clean identity badges frequently. As for lanyards, these could be changed frequently or disposed of altogether in preference to clipped-on identity badges.

Although it is not easy to establish the precise role that identity badges and lanyards may play in transmission of nosocomial infections, our study adds to the growing data on HCWs’ clothing and equipment as potential vectors. Unlike ties, identity badges are constantly touched by HCWs’ hands, and this action can recontaminate hands with pathogens, even after hand hygiene procedures have been followed. Regular disinfection of identity badges may reduce bacterial pathogen contamination, but, ultimately, strict staff hand hygiene is the best way to prevent cross-infection.

1 Identity badge contact with patient

2 Identity badge, lanyard and connections sampled

A: Front and back surfaces of identity badge. B: Two 9 cm lengths of the lower lanyard. C: Connections (eg, clips, keys, pens). D: Distal edge of badge.

5 Lanyard imprint on agar plate

Large pink mucoid colonies of Klebsiella spp are visible on MacConkey agar.