How does the body react to an infectious disease?

Answer 1

The body has various entrance points for bacteria or virus like that of the skin pores, the mouth, nose, eyes, any other open orifice where when not cleaned or are susceptible to infection might be the cause of disease. Infections may come from contaminated food, water, air, dirty hands, sexual contact, and open wounds. Non-Infectious Diseases can arise from exposure to toxins or by genetic defects and vulnerabilities.

Answer 2

Infectious diseases are usually caused by microorganisms that invade the body and multiply. Invasion by most microorganisms begins when they adhere to cells in a person's body. Adherence is a very specific process, involving "lock-and-key" connections between the microorganism and cells in the body. Whether the microorganism remains near the invasion site or spreads to other sites depends on such factors as whether it produces toxins, enzymes, or other substances.

Some microorganisms that invade the body produce toxins. For example, Clostridium tetani in an infected wound produces a toxin that causes tetanus. Some diseases are caused by toxins produced by microorganisms outside the body. Food poisoning caused by staphylococci is one example. Most toxins contain components that bind specifically with molecules on certain cells (target cells). Toxins play a central role in such diseases as tetanus, Toxic shock syndrome, botulism, anthrax, and cholera.

After invading the body, microorganisms must multiply to cause infection. After multiplication begins, one of three things can happen:

• Microorganisms continue to multiply and overwhelm the body's defenses.
• A state of balance is achieved, causing chronic infection.
• The body-with or without medical treatment-destroys and eliminates the invading microorganism.

Many disease-causing microorganisms have properties that increase the severity of the diseases they cause (virulence) and help them resist the body's defense mechanisms. For example, some bacteria produce enzymes that break down tissue, allowing the infection to spread faster.

Some microorganisms have ways of blocking the body's defense mechanisms, such as the following:

• Interfering with the body's production of antibodies or T cells (a type of white blood cell), which are specifically armed to attack the microorganisms
• Being enclosed in protective outer coats (capsules) that prevent white blood cells from ingesting the microorganisms. (The fungus Cryptococcus actually develops a thicker capsule after it enters the lungs for the specific purpose of resisting the body's defenses.)
• Resisting being split open (lysed) by substances circulating in the bloodstream
• Producing substances that counter the effects of antibiotics

Microorganisms that do not at first have ways of blocking the body's defenses sometimes develop them over time. For example, some microorganisms exposed to penicillin become resistant to that drug.

Answer 3

First, the term "infectious disease" covers many types of illness, from common viral illnesses like the common cold to childhood diseases and HIV-Aids (viral). It also includes common bacterial infections, such as Strep throat to uncommon infections, such as MERSA. In each of these, the body is under "attack". Luckily, the body has several types of response to attacks.

The body's immune system first checks to see if you ever fought "this" infection before, or a similar infection. Your body makes antigens if you've had the infection before, so for example, you normally have Mumps and Measles only once. But, sometimes the body's antigens cannot contain a new attack or the attacker changed somehow. For example, the virus that causes measles in childhood remains in the body and some people over age 50 will develop a case of shingles, caused by the same virus but in a changed attack.

Second, the immune system instructs the lymph system to try to contain the illness. The attacker plus the immune system 'battle' at the cellular level, with the body sending antigens, macrophages, and increased blood to sites of "attack". White blood cells join the fight. Increased activity at the cellular level generates energy that humans experience as heat. When we have a fever, the respiratory system and skin (dermis) joins the fight by helping to reduce heat through perspiration, convection of heat away from the body, and evaporation. Up to 30% of heat is lost through the scalp and head where numerous blood vessels are closest to the skin. The circulatory system increases its work, delivering more oxygen to the cells which are fighting the illness. If respiratory, the infection plus the bacteria make mucous; we cough and blow our noses to remove mucous from airways. If urinary, the body also causes mucous, which often alerts us to infection through changed appearance and quantity of urine.

Depending on the type and cause of the infection, humans often need (and want) a medication. Viruses only respond to an anti-viral med--but viruses change rapidly, so humans have developed few medications to fight viruses. Bacteria usually respond to antibiotics, except that if a person has overused antibiotics before, they work less effectively or do not work at all. This is because just like humans develop antigens, the bacteria themselves develop resistances to medications.

This is just a fast overview of some of the body's processes when fighting an infection. There is a lot more "work" the body does that I haven't mentioned.

Answer 4

by cuts and not careing for them

Answer 5

it eats pie