The cells that circulate in the bloodstream are generally divided into three types: white blood cells (leukocytes), red blood cells (erythrocytes), and platelets (thrombocytes). Abnormally high or low counts may indicate the presence of many forms of disease, and hence blood counts are amongst the most commonly performed blood tests in medicine, as they can provide an overview of a patient’s general health status. A CBC is routinely performed during annual physical examinations in some jurisdictions.
Bacterial and viral infections can both cause symptoms such as malaise, fever, and chills. It can be difficult to distinguish which is the cause of a specific infection. It’s important to distinguish, because viral infections cannot be cured by antibiotics.
For infection to occur in a human, the chain of events must happen. Infections do not occur by chance but involve many factors. The chain of events involves several steps which include the infectious agent, reservoir, susceptible host, portal of entry, mode of transmission and portal of exit. Each of the links must be present in a chronological order for an infection to develop. Understanding these steps helps health care workers target the infection and prevent it from occurring in the first place. Each one of these links has an integral role in infection