Microbiology Test #3

The study of disease

The study of the cause of a disease

The development of the disease

Colonization of the body by pathogens

An abnormal state in which the body is not functioning normally

Bacteria on the body that permanently colonize the host

The relationship between normal microbiota and the host

When one organism benefits and the other is unaffected

When both organisms benefit

When one organsim benefits at the expense of the other

Normal microbiota that can get into a sterile environment and could cause infection

Live microbes applied to or ingested into the body, intented to exert a beneficial effect

A change in the body function that is felt by the patient as a result of a disease

A change in the body that can be measured or observed as a result of disease

A specific group of signs or symptoms hat accompany a disease

A disease that is easily spread or just spread from one host to another

• 1. The same pathogen must be present in every case of the disease.
• 2. The pathogen must be isolated from the disease's host and grown in pure culture.
• 3. The pathogen from the pure culture must cause the disease when it is inoculated into a healthy, susceptible lab animal.
• 4. The pathogen must be isolated from the inoculated animal and must be shown to be the orginal pathogen.

A fraction of a population that contracts a disease during a specific time

A fraction of population having a specific disease at a given time

Disease that occurs occasionally in a population

Disease constantly present in a population

Disease acquired by many hosts in a given area in a short time

Worldwide epidemic

Immunity in most of a population

Symptoms develop rapidly

Disease develops slowly

Symptoms between acute and chronic

Disease with a period of no symptoms when the causative agent is inactive

Pathogens are limited to a small area of the body

Bacteria in the blood

Growth of bacteria in the blood

Toxins in the blood

Viruses in the blood

• -Short urethra in females
• -Inherited traits, such as the sickle cell gene
• -Climate and weather change
• -Age
• -Fatigue
• -Lifestyle
• -Chemotherapy

• Biological - Pathogens reproduce in vectors
• Mechanical - Anthropod carries pathogen on feet

• -Mucous membranes
• -Skin
• -Parental route

• ID₅₀ - The infectious dose for 50% of the test population
• LD₅₀ - The lethal dose (of a toxin) for 50% of the test population

• Endotoxin - Part of the outer portion of the cell wall of a gram (+) bacteria. They are liberated when the bacteria die and the cell wall breaks apart
• Exotoxin - Produced inside mostly gram (+) bacteria. They are then secreted or released following lysis into the surrounding medium

Exotoxin

• -Respiratory tract
• -GI tract
• -Genitourinary tract
• -Skin
• -Blood

• -Salts inhibit microbes
• -Lysozyme hydrolyzes peptidoglycan
• -Fatty acids inhibit some pathogens

• Body orifices, epithelial cells glued to an extracellular matrix, cell secrete mucus, some have cilia.
• 1. Lining in your mouth
• 2. Digestive tract
• 3. Urogenital tract
• 4. Respiratory tract
• 5. Lining interior of nose

• -Staphylococci
• -Micrococci
• -Diptheroids

• Exanthem - Skin rash caused by an infection
• Enanthem - A rash on a mucous membrane caused from an infection

Small fluid-filled lesions. Smaller than 1cm.

Larger fluid-filled lesion. Larger than 1cm.

Flat lesion (often reddish)

• Raised lesion. Deeper in the skin.
• - Pustules are pus filled papules

Infections of hair follicles

Folliculitis of an eyelash

Abscess, puss surrounded by inflamed tissue

Extensive furuncle invading other tissue around the infection

Localized pustules that became crusted and rupture

Exfoliate toxin. Top layer of skin peels. Neonates.

Entire body desquamation. Systemic shock.

Infects dermal layer of skin

Attack of solid tissue

Attack of muscle

Attack of tissue covering muscle

• P. aeruginosa - Gram (-) aerobic rod. Produces blue-green pus.
• Associated with:
• -Pseudomonas dermatitis
• -Otitis externa
• -Post-burn infections

• Acne is the occurrence of inflamed or infected sebaceous glands in the skin.
• Caused when sebum channels are blocked with sled cells, deep scaring infections.
• Treated with isotretinoin treatment, antibiotics, peroxide, and visible blue light for some treatments.

• Scabies - mite sacoptes scabiei burrows in skin to lay eggs.
• Pediculosis - pediculus humanus capitis (Head lice) P.h. corporis (body louse). Feed on blood, lay eggs in hair.
• Treatment - Topical insecticide treatment

• -Skull or vertebral fractures
• -Medical procedures
• -Along peripheral nerves
• -Blood or lymph

• Symptoms - Fever, headache, stiff joints (neck), followed by nausea and vomiting, convulsions, and coma.
• Treatment - Diagnosis by gram stain of CSF. Treated with cephalosporins.

• Cause - Clostridium tetani, Gram (+), endospore forming, obligate anaerobe.
• Symptoms - Drooling excessive sweating, fever, hand or foot spasms, irritability, swallowing difficulty, uncontrolled urination or defecation.
• Prevention and Treatment - Vaccination with tetanus toxid booster. Treatment with tetanus immune globulin.

• Cause - Clostridium botulirium, gram (+), endospore forming, obligate anaerobe. Disease due to ingestion of botulinal toxin.
• Symptoms - Flaccid, Paralysis.
• Prevention treatment - By proper canning. Nitrites prevent endospore germination. Treated with supportive care and antitoxin.

• Mycobacterium leprae. Acid-fast rod that grows best at 30^o.
• Tuberculoid form - loss of sensation in skin area, positive lepromin test.
• Lepromatous form - disfiguring nodules over body, negative lepromin test.

• Cause - Trypanosoma brucei gambiense (chronic) and T. b. rhodesiense (more acute). Protozoa.
• Vector - Tsetse fly.
• Afflicted and Where - 60 million + people, Sub-Saharan African regions.

• Cause - Trypansoma cruzi (protozoa)
• Vector - Reduviid bug (kissing bug)

Bacteria growing in the blood

One sign of sepsis. Lymph vessels are inflamed and visible

Decrease in blood pressure

Low blood pressure that cannot be controlled

• Gram (-) - Endotoxins, antibiotics can worsen condition by killing bacteria.
• Gram (+) - nosocomial.

Childbirth fever. A serious form of septicemia contracted by a woman during or shortly after childbirth, miscarriage or abortion. UTI, breast infection, and/or respiratory tract infection can cause it.

Inflammation of the endocardium

Alpha-hemolytic streptococci from mouth

S. aureus from mouth

Strep antibodies have an affinity for certain body tissues such as the heart valves and kidney tubules. Your immune system starts to attack your own cells in these areas and can lead to conditions of heart valve disease and glomerular nephritis and rheumatic fever.

Francisella tularensis AKA rabbit fever or deer fly fever. Transmitted from rabbits and deer by deer flies.

• Brucella (several species). Gram (-) rod that grow in phagocytes.
• Transmitted via milk or contact with infected animals.
• Symptoms are undulating fever that spikes to 40^oC every morning. Abnormal pain, back pain, chills, excessive sweating, fatigue, fever, headache, joint pain, loss of appetite, weakness, weight loss.