DEAR DR.PAUL: What exactly are bacteria? Are all bacteria dangerous? And are bacteria the same as viruses?
DR.PAUL ANSWERS: Very good question, because in pediatrics a lot of the illnesses seen are infections. There are basically three types of germs that infect humans: bacteria, viruses and moulds(or fungi). Let me focus on your specific question. Bacteria are living “uni-cellular” organisms, which means they are made up of one cell. Each bacterial cell has the capacity to live, grow and reproduce itself. Bacteria reproduce themselves by dividing. In other words, one bacterial cell, will divide into 2, then into 4 and into 8, and so on. Bacteria are tiny and cannot be seen be the naked eye. So as a “bacterial family” grows, millions of individual bacteria are formed and in fact, seen only under a microscope.
There are hundreds of different types of bacteria. Some that can cause disease in humans and animals while others, which do not cause any disease but may protect us from other more dangerous forms of infections. The bacteria that can cause disease are known as “pathogenic”. Interestingly, some bacteria can only survive in cold temperature, yet others need warm or even hot temperatures to live. Pathogenic bacteria enter the body from a few possible routes: One can breath in a bacteria, ingest or eat food covered with bacteria or the infection can get in through the skin. Depending on the type of bacteria and from where it enters the body, various infections can occur including brain(meningitis), ear, throat, sinus, stomach/intestinal, urinary, blood, bone and skin infections.
How do bacteria cause infection? This depends on the type. Some bacteria cause infections just by growing and living in a certain part of the body. The presence of these germs triggers our body’s defense or immune system to act. This reaction, known as inflammation features redness, swelling and warmth around the area of the infection (a skin infection for example). In other circumstances, bacteria make certain chemicals called toxins which actually enter the body and cause symptoms and sickness, possibly throughout the body.
How are bacterial infections treated? The best approach is prevention. By far, one of the most important advances in medicine over the last century have been vaccines or immunization. Thanks to the development of bacterial specific vaccines, illnesses like Diphtheria, Tetanus, and Pertussis, have almost disappeared. Over the last 15 years, newer vaccines have become available which protect against even more infections including meningitis, pneumonia, and severe throat, bone and skin infections. Another important advance against bacterial infections are antibiotics which have also saved countless number of lives.
To answer your last question; Yes, there is a difference between bacteria and viruses. Viruses are very tiny, in fact, much smaller than bacteria. They infect by entering the and reproducing inside the body’s cells. By doing so they destroy the cells they infect and spread. Like bacteria, there are pathogenic and non pathogenic viruses. However, unlike bacteria, viruses are not affected by antibiotics.
FOR RELATED DR.PAUL LINKS VISIT:
Infection Prevention Fact Sheet
Antibiotic Fact Sheet
Immunization Section
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