A public health microbiologist trainee job focuses on learning to work in a laboratory to test for, identify, and contain diseases and microscopic organisms that cause health problems. You undergo training under the supervision of experienced public health microbiologists. You learn safe specimen handling and practice the methods that microbiologists use to test samples for evidence of disease. Your duties can also include assessing environmental samples, such as tap water or soil, for evidence of contamination. In addition to sample assessment, you document findings and receive training in the use of lab equipment, such as centrifuges, incubators, and microscopes.