Routine blood tests in case of a cold mainly look at specific values such as white blood cells, hemoglobin and their classification. A routine blood test for a cold that shows a high total white blood cell count and a high total and percentage of classified cells, such as neutrophils, and a normal total and percentage of lymphocytes and monocytes, indicates that the pathogen causing the cold is bacteria. If the blood test shows a high total white blood cell count and a high total and percentage of classified lymphocytes and monocytes, this indicates that the agent responsible for the cold is a virus. In addition, the hemoglobin level should be checked. If it is lower than normal, the most common indication is nutritional anemia, which should be corrected in time to improve immunity and strengthen the ability to resist pathogens.