1 Exam 4 Microbe Human Interactions

Before birth fetus’ are thought to be?

Sterile

Where do babies get their bacteria after birth?

Vagina

Breast Milk

Food

People

Resident microbiota

always present

Transient microbiota

Present for short periods of time when conditions are appropriate.

Where are the highest number of bacteria located in the body?

Large Intestines

Resident flora include what?

Bacteria

Fungi

Protozoa

Viruses

Archaea

Arthropods

Bacterial flora benefit the host how?

By preventing overgrowth of harmful microbes.

What are the relationship classifications between flora and host?

Symbiotic

Nonsymbiotic

What are the classifications of Symbiotic Relationships?

Mutualism

Commensalism

Parasitism

Mutualism

Both members benefit

Commensalism

One benefits, other unaffected

Parasitism

One organism benefit and the other is harmed

What are the classifications of Parasites?

Ectoparasite

Endoparasite

Intracellular

Ectoparasite

External surface

Endoparasite

Internal Surface

What are the classifications of Nonsymbiotic relationships?

Synergism

Antagonism

Synergism

Members cooperate and share nutrients

Antagonism

Some members are inhibited or destroyed by others.

Intracellular parasites

Live inside cell

What is an example of a intracellular parasite?

Rickettsia

What is an example of a endoparasite?

Worms

What are some examples of microbial antagonism, between species?

Compete of nutrients

Produce harmful substances to prevent pathogens from growing

chain environmental conditions like pH

True Pathogen

Pathogens capable of causing disease in healthy people with normal immune systems

Opportunistic Pathogen

Non considered pathogenic in healthy people, but under certain conditions can cause infection.

Portal of Entry

Site in the body where the pathogen etners

Portals of entry in the mucous membranes.

Respiratory

Gastrointestinal

Genitourinary

Conjunctiva

Portals of entry for Skin

Hair follicles

Sweat Glands

Open wounds

Burns

Parenteral Route

Microbes’ places directly into tissue beneath skin or mucous membranes

Portals of entry of Placenta

Some bacteria can penetrate the placenta blood barrier.

What bacteria can penetrate the Placenta?

Syphilis Spirochete

Adherence rule

Microbe must be able to attach to host tissue once it has entered in order for it to cause diseases

What are some mechanisms of attachment?

Attachment Pili

Adhesive Slimes or biofilms

Hooks

Barbs

Capsules

Exoenzyme types.

Hyaluronidase

Coagulase

Kinase

Hyaluronidase

Breaks down hyaluronic acid in connective tissue.

Coagulase

Causes coagulation of plasma

Kinase

Dissolves blood clots

What are some examples of kinase?

Streptokinase

Staphylokinase

Preferred portal of entry

Some pathogens only cause disease if they enter body through a specific portal.

Griffith Experiment proved that

bacterial species with a capsule is more virulent than same species without a capsule.

What does Mucinase do?

Digests protective coating on mucous membranes.

What does Hemolysins do?

Breaks down red blood cells

Release of nutrients (iron)

What does Leukocidins do?

Kills host leukocytes and reduces their activity.

What does Collagenase do?

Breaks down collagen.

Toxins

A poisonous substance

What do toxins do?

Produce fever

Cardiovascular disturbances

Diarrhea

Shock

Inhibit protein synthesis

Destroy blood cells

disrupt nervous system.

Exotoxins

Proteins secreted from a cell into surrounded tissue.

Examples of exotoxins

Neurotoxins

Enterotoxins

Cytotoxins

Neurotoxins

Act on nervous system

What are some microbes that use neurotoxins?

Clostridium tetani

Clostridium botulinum

Enterotoxins

Act on digestive system

What are some microbes that use enterotoxins?

Staphylococcus aureus

Vibrio cholerae

Staphylococcus aureus produces what toxin?

Staphylococcus enterotoxin

Food poisoning

Vibrio cholerae produces what toxin?

Vibrio/Cholera toxin

Cytotoxins

act on cells

Diphtheria toxin does what?

Inhibit protein syntehsis

Polysaccharide is an example of a?

Endotoxin

What does polysaccharide do?

Act as pyrogen

Resents hypothalmic thermostat

can cause shock

blood pressure drops

What Gram bacteria has polysaccharides?

Negative

When is polysaccharides release?

Bacterial death.

What type of Polysaccharides are used by Gram Negative Bacteria

Lipopolysaccharides.

Patterns of infection classifications.

Local

Systemic

Focal

Secondary Infection

Local Infections

Infection confined to specific area of body

Systemic infections

Affects many areas of body, travel through blood and lymph.

Example of a systemic infection.

Rabies.

Focal infections

spread of a local infection or toxins through blood or lymph resulting in infection confined to certain areas of the body.

Secondary infections

Occurs when an initial, or primary infection is complicated by another infection caused by a second microbe.

What are the classifications of disease severity and duration?

Acute

Chronic

Latent

Acute disease

Develop rapidly, short duration, high fever

What is an example of a acute diease?

Flu

Chronic disease

Develop slowly, longer duration

What is an example of a chronic disease?

Hepatitis

Latent disease

Disease with periods of inactivity.

What is an example of a latent diease?

Malaria

Shingles

What does Erythrogenic Toxin do?

Damage capillaries under skin to produce a rash.

What bacteria produces Erythrogenic toxins?

Streptococcus pyogenes.

Portal of Exit

The route the pathogen leaves the body.

What are some portals of exit?

Mucus

Sputum

Nasal Drainage

Skin Scales

Feces

STIs

Blood

Coughing Sneezing

Reserviors

The primary habitat in the natural world form which a pathogen originates.

What are the classifications of reservoirs

Non-Living

Living

Non-living Reservoir examples

Soil

Water

Contaminated surfaces.

Living Reservoir examples

Living carries such as humans.

Carrier

An individual who inconspicuously shelters a pathogen and can spread it to others without knowing.

Vectors

A living animal that transmits an infectious agent from one host to another.

Biological vectors

Participates in the pathogen’s life cycle

Infected with the pathogen

Transmitted by bites and shitting

What are some examples of biological vectors?

Mosquitoes (Heartworm, malaria)

Mechanical vector

Insect that carries pathogen on body parts.

What are some factors of a mechanical vector?

Not part of the pathogen’s life cycle

Not infected with the pathogen

What is an example of a mechanical vector

Fly walks in dog crap walks on human food.

Zoonosis

A disease that is found in animals but can be transmitted to humans.

Communicable disease

Infectious disease is transmitted from one infected host to another

Noncommunicable Diseases

Infectious disease is acquired from the environment.

Examples of communicable diseases

Chicken Pox

Pink Eye

Colds

Flu

HIV

Examples of noncommunicable diseases

Food poisoning

Tetanus

What are the classifications of the patterns of disease transmission?

Vertical

Horizontal

Vertical Disease Transmission

The disease is transmitted from parent to offspring.

Horizontal Disease Transmission

Disease is spread through a population from one infected person to another.

Examples of vertical disease transmission

Placenta to baby

Examples of horizontal disease transmission.

Kissing

Sneezing

Direct Transmission

Body contact between individuals

Droplet Transmission

Mucus from coughing, sneezes and speaking carry microbes.