Infections and the Immune System
The human Body is at constant war against disease-causing pathogens (germs), which can enter the Body through inhaled air, ingested food or water, broken skin, insect or animal bites, and sexual contact. Once on or inside the body, pathogens try to survive and reproduce. Most do not succeed. Many succumb to the Body’s internal heat or chemical environment, or to “friendly bacteria,” while others are expelled in mucous, urine, sweat, and feces. Those that survive do so by preying on healthy cells and tissue. Some pathogens can live only in certain types of tissue, while others can spread throughout the Body. The three-part process of invasion, growth, and the Body’s reaction constitutes infection. Though most infections are minor and short-lived, more and more are evolving into serious and even life-threatening diseases.
Once a pathogen invades the Body, our natural immune system counterattacks. Proteins called antibodies team up with special white blood cells to neutralize and destroy pathogens. The immune system is also able to remember contacts with a particular pathogen so that it can suppress repeat invasions. This cellular memory gives the body immunity against countless disease-causing pathogens.
Rapid immune system response stops or weakens most, but not all infections. Sometimes immune cells fail to recognize and attack pathogens, especially unfamiliar ones. At other times the Body’s counter-attack isn’t enough to stop the spread of harmful organisms in our Body.
How our Bodies Cope with Infections?
Although the immune system is exceedingly complex, some simple factors can weaken it. Higher than normal physical and emotional stress (including depression) are common underlying factors. Chronic or severe illnesses and surgery can leave the defense system exhausted and make convalescence (the gradual recovery of health and strength) particularly slow.
Poor and inadequate diet greatly interferes with the normal functioning of the immune system. Empty calories in highly processed foods and sweets not only fail to provide nourishment but are also harmful. Obesity, poor physical condition, and lack of activity are other contributing factors. Many medications, especially cortisone and antibiotics, affect the defense system adversely, particularly when they are taken for long periods. The immune system is also sensitive to toxic substances, including excessive alcohol and heavy metals. Individual constitution plays a role, and those with a weaker system must work harder to keep their immune system healthy.
The pathogens that cause infections are bacteria, fungi, animal parasites, and viruses. Bacteria, fungi, and parasites generally invade body tissue, steal nutrients from healthy cells, and release toxins. Some parasites – which can range in size from single-celled protozoa to visible worms – can kill healthy cells. Viruses are sub-life forms that survive only by invading living cells and multiplying inside them.