Microbiology Demystified

13 CHAPTER 197 Epidemiology and Disease No one wants to give a friend a cold, so we always cover a sneeze with our hands. Howeve ...

ulation. Epidemiologists use this information to design ways of preventing and controlling outbreaks of disease. Epidemiology is ...

and the rate of morbidity. The level of destruction will be so large that it will cause a significant public health concern. A d ...

signs or symptoms. These disease-causing agents can even be contagious during the recovery period. When a person becomes symptom ...

minated water infected with human or animal fecal matter can contain many diseases-causing agents. An example is the bacterium V ...

isms can transmit disease through air. They can travel one meter or more through an air medium to spread infection. Airborne pat ...

the life cycle of the pathogen. An example of a host organism is a mosquito that infects a human with malaria. Other diseases ca ...

skin (no cuts or abrasions), mucous membranes, a good cough reflex, normal gastric juices, and normal bacterial flora. If a micr ...

to a water pump. He concluded that individuals who died from cholera drank water contaminated with human feces. Snow’s study and ...

Immunizationis an effective means of controlling the spread of communica- ble diseases by the use of safe vaccines. A vaccine is ...

have a lowered resistance to disease, thus making them more susceptible to infections. Many of these patients are said to be “co ...

The total number of old and new cases of a disease is called (a) incidence (b) prevalence (c) morbidity rate (d) prevalence rat ...

What is the period of time called when a disease is contagious and com- municable before showing signs and symptoms and during ...

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14 CHAPTER 211 Immunity There’s a battle going on beneath your skin. Thousands of microbes crawl into every nook and cranny of y ...

transplanted tissues, and insect venom. Parts of these substances are called anti- gens,or immunogens. Antigens can be polysacch ...

also passed to the baby in the first secretion of breast milk, called colostrum, during breast-feeding. Artificially acquired ac ...

CELL-MEDIATED IMMUNITY Cell-mediated immunityinvolves specialized lymphocytes called T cells, also known as T lymphocytes, to at ...

binding sites. The number of antigen-binding sites is called the antibody’s val- ence. There are at least two antigen-binding si ...

IgA IgA immunoglobulinis the most common antibody in body secretions and in mucous membranes. It consists of about 15 percent of ...