Related Experiment Video
Updated: Jun 13, 2026

Cell Culture Techniques and Practices to Avoid Contamination by Fungi and Bacteria in the Research Cell Culture Laboratory
Published on: July 7, 2023
Contaminations of laboratory surfaces with Staphylococcus aureus are affected by the carrier status of laboratory
1State Laboratory Basel City, Biosafety Laboratory, Basel, Switzerland.
Aim:
As a biosafety laboratory, we take samples from surfaces in microbiological laboratories to survey the handling of micro-organisms. Whereas contaminations with other micro-organisms were rare, Staphylococcus aureus was found in the working environment of many laboratories. As 20-60% of the healthy population are carriers of S. aureus we wanted to asses the effect of carriers on our sampling results.
Methods And Results:
Nasal swabs of staff members in nonmicrobiological laboratories and offices as well as surface samples from their personal work environment were taken and analysed for S. aureus DNA. In addition S. aureus strains were isolated using S. aureus-specific agar plates and analysed by randomly amplified polymorphic DNA (RAPD)-PCR and multilocus sequence typing (MLST). Our data show that contaminations with S. aureus in nonmicrobiological environments are common with 29% of the surface samples containing S. aureus DNA. In the working environment of carriers, the number of contaminations was significantly increased compared to the environment of noncarriers.
Conclusion:
The carrier status of staff members significantly affects the number of contaminations on laboratory surfaces. Therefore, even in the absence of intentional handling of S. aureus, contaminations can be detected on a substantial amount of surfaces.
Significance And Impact Of The Study:
Sampling procedures need to be adapted based on these results with respect to the locations where samples are taken and the threshold for significant contaminations. Because of its wide distribution, S. aureus can serve as a marker for hygienic standards in laboratories.
Related Concept Videos
Standard Precaution
Hand hygiene is the most crucial means to prevent the transmission of disease. Employers are legally required to provide their workers with personal protective equipment (PPE) to minimize exposure or contact with...
Staphylococcal Skin Infections
Healthcare Associated Infections II: Preventive Measures
The best practices for preventing healthcare-associated infections include hand hygiene, patient risk...
Healthcare Associated Infections I: Iatrogenic, Exogenic and Endogenic
HAIs significantly increase the cost of health care. Extended stays in healthcare institutions, increased disability, increased costs of medications, including specialized antibiotics, and prolonged recovery times add to the patient's expenses and the healthcare institution and funding bodies. Common...
Infection
The chain begins with pathogens: bacteria, viruses, fungi, prions, or parasites such as protozoa helminths. These can be present on the skin as transient or resident flora, or they can be acquired from the environment. Identifying and treating the type of infection and...
Transmission-based Precautions II: Airborne and Protective Environment
Airborne precautions:
Use airborne precautions when treating patients known or suspected to have diseases that spread through the air—for example, tuberculosis or measles. These organisms are present in smaller droplets expelled by an infected person and...

