Our Methods

The participant’s smartphone will be swabbed using a consistent, dense zigzag motion across front and back exposed surfaces (including the exterior of any phone case). In contrast, the area beneath the case will not be included. 

The swab will then be placed into liquid Amies transport medium, kept chilled, and transported to the laboratory within 24 hours. 

In the laboratory, 50 µL of each swab specimen will be inoculated into tryptic soy broth (TSB) and incubated at 35°C with shaking at 200 rpm for overnight enrichment. Meanwhile, the 50 µL of the swab specimen will be inoculated onto a plate count agar (PCA) and incubated at 35°C for 48 hours. The colonies will be counted.

Then, 50 µL of enriched TSB culture will be plated onto HiCrome MRSA agar using the spread plate method and incubated at 35°C for 48 hours. 

Colonies that show green pigmentation will be picked as suspected MRSS and subcultured onto blood agar to obtain pure isolates. 

These isolates will then be Gram-stained to check for Gram-positive cocci in clusters, consistent with Staphylococcus spp..