Yersinia pestis, Direct Fluorescent Antibody Stain (DFA), 200x Magnification…Positive identification of the bacillus may be facilitated through the application of DFA stain and its affinity for the Y. pestis’ capsular antigen.
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Yersinia pestis, Direct Fluorescent Antibody Stain (DFA), 200x Magnification. CDC 2057 – US Government public domain image