What is the most common type of pathogenic bacteria?

The most common type of pathogenic bacteria is bacilli. Bacilli are rod-shaped bacteria that can be responsible for a range of infectious diseases. Their shape contributes to their ability to survive in different environments, making them versatile and widespread. Many pathogenic bacteria that cause diseases in humans fall into this category, such as those responsible for tuberculosis and anthrax.

While cocci, spirilla, and vibrio are also types of bacteria, they represent different forms and are less prevalent as pathogens compared to bacilli. Cocci are spherical, spirilla are spiral-shaped, and vibrio resemble a comma shape. Each type can cause disease; however, bacilli are more frequently identified as common pathogens due to their wide variety and ability to thrive under various conditions. This adaptability often leads to an increased likelihood of transmission and infection in various environments.