<prompt> a young boy had a flea bite while working in a wheat grain goes down .after 5days he developed fever and had axillary lymphadenopathy. a smear was sent to he laboratory to perform a specific staining.which one of the following staining method would help in identification of the suspected pathogens ?albe stainingziehl neelsen stainingmcfaydens stainingwayson staining  <response>: Yersinia Non lactose fermenting Gram negative rods Motile except Y. pestis 10 species, only Y. pestis plague, Y. enterocolitica, Y pseudotuberculosis enteric disease, septicaemia pathogenic for animals and man Demonstrate bipolar staining in Giemsa stained smears from animal tissues Serotyping and biotyping used to discriminate between strains 10 serotypes of Y pseudotuberculosis, serotypes I, II and III contain majority of pathogenic isolates 5 biotypes and more than 50 serotypes of Y enterocolitica LABORATORY DIAGNOSIS Yersinia pestis can be identified in the laboratory by both bacteriologic and serologic methods Diagnosis can be made from a variety of samples, including blood, aspirates from involved lymph nodes, skin scrapings, cerebrospinal fluid, urine, and sputum Yersinia pestis appears as a pleomorphic gram negative rod and may appear as a single cell -2.0 x 0.5pm or in sho chains in smears ref : ananthanaryana 9th ed 