For the detection of acid fast bacteria (AFB) that cause infectious illnesses Ziehl Nielson (ZN) stain is utilised. The most prevalent illness brought on by AFB mycobacterial species is tuberculosis which typically affects the lungs but can also damage the brain bones or kidneys. Sputum a mucus that is coughed up from the lungs and is thick murky and sticky serves as the sample for this examination. The symptoms of tuberculosis include fever abrupt weight loss a chronic cough weariness headache and others. It is spread through coughing and sneezing. A positive test signals the need for prompt medical attention. Additionally the effectiveness of current TB therapy is evaluated using this test