What type of contamination is it on the agarose plates (This is found in a plaque assay)?

16 February 2023 0 6K Report

I did a plaqe assay with an arbovirus. When I went to count the plaques the next day of pouring the second overlay, I found this contamination (shown on the attached plate). I would like to figure out what that contamination was and its source. I would highly appreciate any suggestion or help.

Have a great day!

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