Chapter 5: Disease and Disease-Producing Organisms

Overview

Key Terms acute fungus protozoa antibiotic helminth sign antisepsis host sterilization asepsis infection symptom bacteria microorganism syndrome chronic nosocomial infection systemic diagnosis opportunistic infection therapy disease pandemic toxin disinfection parasite vector endemic pathogen virus endospore pathophysiology epidemic prion etiology prognosis

Studies of Disease Learning Outcomes Define disease and list seven categories of disease Explain the meaning of a predisposing cause of disease and list seven such causes Describe the science of epidemiology and cite some types of studies done in that field

Studies of Disease Disease Abnormality of structure or function of part, organ, or system May be felt or observed by others May have a known or unknown cause Severity of effects may be variable

Studies of Disease Disease Categories Infection Degenerative diseases Nutritional diseases Metabolic disorders Immune disorders Neoplasms Psychiatric disorders

Figure 5-1 Rheumatoid arthritis.

Studies of Disease Disease Causes Age Gender Heredity Living conditions and habitsw Emotional disturbance Physical and chemical damage Preexisting illness

Studies of Disease Epidemiology The study of the cause of disease in populations Disease statistics Incidence Prevalence Mortality rate Disease categories Epidemic Endemic Pandemic

Figure 5-2 Influenza epidemic.

✓ Studies of Disease Checkpoints 5-1 What is a disease? 5-2 Name several causes of disease. 5-3 What is the definition of a predisposing cause of disease 5-4 Identify three types of statistics typically collected by epidemiologists. Answers: #-# Answer here #-# Organs working together combine to form systems.

Disease Diagnosis, Treatment, and Prevention Learning Outcomes Define terms used in the diagnosis and treatment of disease Define complementary and alternative medicine; cite several alternative or complementary fields of practice

Disease Diagnosis, Treatment, and Prevention Symptoms Signs Disease classification Syndrome Acute Chronic Subacute Prognosis

Disease Diagnosis, Treatment, and Prevention Medication Surgery Other therapies Physical therapy Occupational therapy Respiratory therapy Nutritional therapy Counseling and support groups

Figure 5-3 Physical therapy.

Disease Diagnosis, Treatment, and Prevention Seeks to stop disease before it actually happens Stop smoking Limit alcohol use Eat a healthy diet Maintain a healthy weight Get regular exercise Health promotion organizations WHO CDC

Disease Diagnosis, Treatment, and Prevention ✓ Disease Diagnosis, Treatment, and Prevention Checkpoints 5-5 What is the identification of an illness called? 5-6 What is a symptom? Answers: #-# Answer here #-# Organs working together combine to form systems.

Infectious Disease Learning Outcomes Explain methods by which microorganisms can be transmitted from one host to another

Infectious Disease Pathogens Microorganisms Parasites Infection Local Systemic Modes of transmission Direct Indirect

Infectious Disease Portals of entry Skin Respiratory tract Digestive system Urinary and reproductive systems

✓ Infectious Disease Checkpoints 5-7 What is a communicable disease? 5-8 What is the relationship between a parasite and a host? 5-9 What term describes any disease-causing organism? 5-10 What are some portals of entry and exit for microorganisms? Answers: #-# Answer here #-# Organs working together combine to form systems.

Microbiology – The Study of Microorganisms Learning Outcomes List five types of organisms studied in microbiology and give the characteristics of each List some diseases caused by each type of organism Define normal flora and explain the value of normal flora

Microbiology Types Bacteria (bacteriology) Viruses (virology) Fungi (mycology) Protozoa (protozoology) Algae (algology)

Microbiology Normal Flora Population of beneficial microorganisms that normally grows on and within the human body

Microbiology Bacteria Single-celled organisms Lack a true nucleus Found everywhere Types Anaerobic Aerobic Facultative anaerobes

Microbiology Bacterial Specializations Endospores Flagella Pili

Figure 5-4 Endospores.

Figure 5-5 Flagella.

Microbiology Shape and Arrangement of Bacteria Cocci Bacilli Vibrios Spirilla Spirochetes Rickettsia Chlamydiae

Microbiology Naming Bacteria Genus name: Capitalized and italic species name: lowercase and italic EXAMPLE: Escherichia coli or E. coli

Figure 5-6 Cocci (Gram stained).

Figure 5-7 Bacilli.

Figure 5-8 Curved rods. What feature indicates that the cells in A are capable of movement?

✓ Microbiology Checkpoints 5-11 What categories of organisms are studied in microbiology? 5-12 What term refers to microorganisms that normally live in or on the body 5-13 What are resistant forms of bacteria called? 5-14 What are the three basic shapes of bacteria? Answers: #-# Answer here #-# Organs working together combine to form systems.

Microbiology – The Study of Microorganisms Viruses Extremely small microorganisms Composed of a core of nucleic acid surrounded by a coat of proteins Grow only within living cells

Figure 5-9 Virus size comparison.

Figure 5-10 Virus structure.

Infectious Agents Smaller than Viruses Microbiology – The Study of Microorganisms Infectious Agents Smaller than Viruses Infectious Proteins Prions Composed solely of protein

Microbiology – The Study of Microorganisms Fungi Large group of simple plantlike organisms, few are pathogenic Types Yeasts Single-celled forms of fungi Molds Fuzzy, filamentous forms of fungi

Figure 5-11 Fungi.

Microbiology – The Study of Microorganisms Protozoa Animal-like, single-celled microbes found all over the world Types Amebas Ciliates Flagellates Apicomplexans

Figure 5-12 Some parasitic protozoa. Why are the parasites in E described as intracellular? What is the role of the vectors shown in C and E?

✓ Microbiology Checkpoints 5-15 How do viruses differ from bacteria? 5-16 What group of microorganisms is most animal-like? Answers: #-# Answer here #-# Organs working together combine to form systems.

Parasitic Worms Learning Outcomes List several diseases in humans caused by worms.

Parasitic Worms Parasites with human hosts, also called helminths Helminthology The study of parasitic worms. Types Roundworms Flatworms

Parasitic Worms Round Worms Ascaris Pinworms Hookworms Trichina (trichinosis) Filaria worm (filariasis, elephantiasis)

Figure 5-13 Common parasitic roundworms. What kind of muscle tissue is shown in B?

Figure 5-14 Filariasis.

Parasitic Worms Flatworms Ribbonlike or leaf shaped Tapeworms Flukes

Figure 5-15 Flatworms.

✓ Parasitic Worms Checkpoints 5-17 What is the study of worms called? Answers: #-# Answer here #-# Organs working together combine to form systems.

Microbial Control Learning Outcomes Give some reasons for the emergence and spread of microorganisms today Describe several public health measures taken to prevent the spread of disease Differentiate sterilization, disinfection, and antisepsis Describe techniques included as part of body substance precautions

Microbial Control Some reasons for the emergence and spread of microorganisms today Increase in world population Disruption of animal habitats Increased travel (SARS) Opportunistic infections Changes in food handling

Microbial Control Public Health Sewage and garbage disposal Water purification Prevention of food contamination Milk pasteurization

Microbial Control Aseptic Techniques Sterilization Disinfection Antisepsis

Figure 5-16 Aseptic methods.

Microbial Control Infection Control Techniques Body substance precautions Handwashing OSHA

Microbial Control Antimicrobial Agents Antibiotics (antibacterial agents) Antiviral agents Limited number of effective antiviral drugs Block removal of protein coat of virus Block production of viral nucleic acid Block enzyme production needed to create new virus particles

✓ Microbial Control Checkpoints 5-18 What is the study of worms called? 5-19 What is the single most important measure for preventing the spread of infection? 5-20 What is an antibiotic? Answers: #-# Answer here #-# Organs working together combine to form systems.

Laboratory Identification of Pathogens Learning Outcomes Describe several methods used to identify microorganisms in the laboratory

Laboratory Identification of Pathogens Obtain and label specimens from patients Grow out bacterial cells Isolate individual organisms Multiply to form colonies Stain cells so they can be seen Perform tests to identify organisms

Other Methods of Identification Growth characteristics in liquid and solid media Oxygen requirements Ability of bacteria to utilize various carbohydrates Reaction to various chemicals Serologic (immunologic) tests

Figure 5-17 Isolated colonies of bacteria growing on a solid medium.

Figure 5-18 Gram stained bacteria.

Laboratory Identification of Pathogens ✓ Laboratory Identification of Pathogens Checkpoints 5-18 What are the dyes used to color microorganisms called? Answers: #-# Answer here #-# Organs working together combine to form systems.

Case Study Learning Outcomes Using the case study, describe a virus’ mechanism of infection and the host’s response

Case Study Virus’ Mechanism of Infection Enter host cell Trick host into transcribing viral mRNA Trick host into translating the mRNA into viral protein Make new virus Host’s Response Increase body temperature to slow viral replication Activate immune system to seek out and destroy virus

Word Anatomy Learning Outcomes Show how word parts are used to build words related to disease

Word Anatomy Word Part Meaning Example idio self, separate, distinct An idiopathic disease has no known cause. syn- together A syndrome is a group of symptoms and signs that together characterize a disease. myc/o fungus Mycology is the study of fungus. diplo- double Diplococci are arranged in pairs. strepto- chain Streptococci are arranged in chains. staphylo- grapelike cluster Staphylococci are bacteria in clusters. septic poison, rot, decay Aseptic methods are used to kill microorganisms. -cide kill or destroy A bactericide is an agent that kills bacteria