Types of Virus

Viral
Further information: Table of clinically important viruses
Pathogenic viruses are mainly those of the families of: Adenoviridae, Picornaviridae, Herpesviridae, Hepadnaviridae, Flaviviridae, Retroviridae, Orthomyxoviridae, Paramyxoviridae, Papovaviridae, Rhabdoviridae, Togaviridae. Some notable pathogenic viruses cause: smallpox, influenza, mumps, measles, chickenpox and rubella. Ebola is another pathogenic virus. Viruses typically range from between 20-300 nanometers in length.

Bacterial
Main article: Pathogenic bacteria
Although the vast majority of bacteria are harmless or beneficial, a few pathogenic bacteria can cause infectious diseases. The most common bacterial disease is tuberculosis, caused by the bacterium Mycobacterium tuberculosis, which effect about 2 million people mostly in sub-Saharan Africa. Pathogenic bacteria contribute to other globally important diseases, such as pneumonia, which can be caused by bacteria such as Streptococcus and Pseudomonas, and foodborne illnesses, which can be caused by bacteria such as Shigella, Campylobacter and Salmonella. Pathogenic bacteria also cause infections such as tetanus, typhoid fever, diphtheria, syphilis and leprosy. Bacteria can often be killed by antibiotics. They typically range from between 1-5 micrometers in length.

Fungal
Fungal microbes can cause diseases in humans, animals and crop plants. Fungi most often infect immuno-compromised patients or vulnerable people with a weakend immune system. Most antibiotics cannot be used to treat fungal infections due to the fact that fungi and their hosts both have eukaryotic cells. Most clinical fungicides belong to the azole group. The typical fungal spore size is 1-40 micrometer in length. It's a death promblem