You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is A 5-year-old unimmunized child presented with high fever, sore throat, dysphagia & voice change. Throat swab from a whitish lesion showed the following diagnosis. and explain in detail?
a. DiphtheriaOn Albert staining, C. diphtheriae appears green colored rod shaped bacteria with bluish black metachromatic granules at the poles