Hopkins ABX Guide

Pathogenic Bacteria

Not All Bacteria are Harmful

Not all bacteria are harmful. On the contrary, the majority don’t do any harm. They are prevented from causing an infection or illness by the immune system. Then there are also bacteria that are beneficial. One of the best examples is Lactobacillus acidophilus which lives in human gastrointestinal tract and promotes digestion as well as helps the body fight off bacteria and other microorganisms that can cause harm. Bacteria and other microorganisms such as viruses, fungi and parasites that can be harmful are collectively called pathogens.

Sources of Pathogenic Bacteria and Modes of Transmission

Potentially harmful or pathogenic bacteria can be found just about everywhere including food, water, air, animals, plants,… Some even live in or on the human body and under normal circumstances - until their multiplication doesn’t get out of control - aren’t dangerous or harmful. Pathogenic bacteria are transmitted in many different ways: from person to person through skin-to-skin contact, through body fluids (blood, saliva or/and semen), through contaminated surfaces (for example by sharing utensils, and touching contaminated surface and then mouth, eyes or nose), by eating/drinking contaminated food/water, by inhaling infected airborne droplets of saliva, …

Impact of Pathogenic Bacteria on Human Health

Infection with pathogenic bacteria may not cause any symptoms whatsoever. Also, many bacterial infections resolve on their own. But in some cases, bacterial infection can be fatal. The impact of pathogenic bacteria on human health above all depends on the bacteria that are causing the infection because some are more successful against the immune system’s defence mechanisms and cause more damage to the cells than the others. The severity of symptoms or illness due to bacterial infection, however, also depends greatly on the state of the patient’s immune system.

Individuals with a strong immune system are less likely to contract a bacterial infection and if they do, they usually develop milder symptoms and recover faster than those with a weakened or not yet fully developed immune system. The elderly, chronically ill individuals and young children are thus at increased risk of both contracting an infection and developing illness but they are also at increased risk of developing potentially life-threatening complications.

Preventing Bacterial Infections

Even though pathogenic bacteria can be contracted in virtually countless ways, most bacterial infections can successfully be prevented by the following measures: