We don’t recommend compositing samples, because there is no enrichment step in the testing protocol. Therefore, compositing samples would lower the sensitivity of testing and such render false negatives. In addition, the swab tip is relatively small. Sampling too big of an area would saturate the swab and lower the collecting efficiency.
There are air sampling methods for the SARS-CoV-2 (COVID-19) virus in general. However, the regular filter cassettes will not work because their pore size is larger than virus particles. Liquid impinger with proper medium is a suitable method. There is a study of air sampling of SARS-CoV-2 using SASS®2300 WETTED-WALL AIR SAMPLER at 300 L/min for 30 minutes. There is another study that used polytetrafluoroethylene (PTFE) filter cassettes for taking air samples. However, we have not validated a testing method for air samples.
Yes, the SARS-CoV-2 (COVID-19) analysis can be used for food packaging materials as long as you can use the specialty swab to collect a sample from the food packaging materials’ surface.
It is not recommended to sample more than one location per swab. It some areas, it may make sense to sample the door handle & keypad on a microwave oven, or a keyboard and mouse, with a single swab. However, do not exceed the 100sq cm (or 8″x8″) maximum sampling area per swab.
With each SARS-CoV-2 sampling swab you can sample an area up to 100 sq cm (or 8″x8″).