microbio module 2

Is the uterus considered sterile?

are babies born with a microbiome from their mother?

• yes

• NO microbiome created AFTER birth

What are the 8 Gut Microbiome Functions?

1. food digestion - fatty acid metabolism

2. nutrition- vitamin production

3. xenobiotic processing

4. education and regulation of immune system

5. development of nervous system

6. resistance to outgrowth of pathologic colonizers

7. develop gut mucosa 

8. gut epithelial homeostasis 

• heart and circulatory system 

• liver

• kidneys and bladder 

• lungs 

• brain and spinal cord 

• muscles

• bones

• ovaries/testes

• glands

• sinuses

• middle and inner ear 

• internal eye

Do the following sites have their own microbiome or are they sterile and free from microbiomes?

STERILE NO MICROBIOME 

• blood

• urine in kidnyes, ureters, bladder

• cerebrospinal fluid 

• saliva prior to entering oral cavity 

• semen prior to entering the urethra 

Do the following sites have their own microbiome or are they sterile and free from microbiomes?

STERILE

• skin and contiguous mucous membranes

• upper respiratory tract

• outer opening of urethra

• external genetalia

• vagina

• external ear and canal

• external eye (lides, lash follicles)

are the following free of microbiome?

NO they ALL HAVE MICROBIOME

infection can be caused by __________ or ___________

true pathogens or opportunists (not normally pathogenic) 

• the process through which a disease develops 

• a microbe that causes disease 

• the potential of a microbe to cause disease 

• the measure of the pathogenicity of a microbe

• the number of organisms required to initiate an infection

• pathogenesis 

• pathogen 

• pathogenicity 

•  virulence 

• infectious dose

What is the difference between virulence and infectious dose?

Virulence is the pathogenicity of a microbe

The infectious dose is how much of a pathogenic microbe you need for it to cause an infection

steps of microbial disease pathogenesis

1. finding a portal of entry

2. attaching firmly

3. surviving host defenses

4. causes of damage and disease

5. exiting host

what is the primary route of infection for 

what is the infectious dose of each? 

• measles

• cholera

measles = respiratory = 1 virus 

cholera = ingestion = 100 million virus 

once pathogenic microbes find a portal of entry through the skin, GI, Respiratory tract, Urogenital tract, transplacental, what allows them to ADHERE to host cells?

• glycocalyx

• fimbrae

• flagella

• cillia

• hooks

• suckers

• barbs

• spikes

• receptors

how are pathogenic microbes able to overcome home defenses after entering and adhering?

• slime layer or capsule

• waxy external or cord factor

• leuokocidins (produced by staphyloccous and strptococuses) - kill white blood cells

• altered pathogenicity and antigenic shifts

traits used to invade and establish themselves in the host, also determine the degree of tissue damage that occurs severity of disease 

virulence factors 

dissolve extracellular barriers and allow cells to penetrate through or between cells

exoenzymes

substances produced by microbes that damage or kill host cells (beyond cells involved in defense)

toxins

what is the difference between exoenzymes and toxins? 

exoenzymes are used to break walls of host cells whereas toxins are used to damage and kill host cells 

___________ target the heart, muscles, blood cells, intestinal tract (toxic in tiny amounts)

____________ cause general psychological effects—- fever, malaise, aches, shock

exotoxin- heart, muscles, blood cells, intestinal tract

endotoxins- malaise, fever, aches

can we vaccinate against endotoxins or exotoxins?

The vaccine goes against EXOTOXIN, we have too much endotoxin

what are the 4 distinct phases of infection and disease?

1. incubation

2. prodromal stage

3. period of invasion

4. convalescent

time from initial contact with infectious agent to appearance of first symptoms

agent IS multiplying but damage is insufficient to cause symptoms

how long can one be in the period?

incubation period FIRST PERIOD OF INFECTION

you can be in this period from hours to YEARS (you can have infection multiply but not have a significant effect)

which stage of infection is when you have vague feelingsof discomfort and NONSPECIFIC complaints?

SECOND STAGE - prodroma

which stage of infection multiplies at high levels, becomes well-established; more SPECIFC signs and symptoms

period of invasion

which stage of infection does the person begins to respond to the infection, and symptoms decline

convalescent period - LAST PERIOD

(chronic infection, progression, death)

what are 5 different patterns of infection

1. localized (boil) 

2. systemic (Influenza- can come in through respiratory but WILL circulate throughout the blood) 

3. focal (tuberculosis + streptococcal pharyngitis) - 

4. mixed infection (wounds, gangrene, caries) 

5. primary (urinary infection) allows for secondary (vaginal) infection — pH of vagina suitable now for bacteria

are the following signs or symptoms?

• sore throat

• itchy eyes

• swelling in neck

• painful urination

• itchiness

• difficulty breathing

• chills

signs

are the following signs or symptoms?

• fever

• inflammation

• abnormal chest sounds

• inflamed pharynx

• conjunctivitis

• enlarged lymph nodes

• bacteriuria

• leukocytosis

signs

a disease identified through a collection of subjective symptoms and objective signs 

syndrome

what are 2 other terms for asymptomatic?

• subclinical

• inapparent

what is the difference between a latent and chronic carrier post recovery?

latent carrier has disease that can cause symptoms periodically but DOES NOT SHED OUTSIDE OF BODY

chronic carrier is latent and CAN SHED

what is the difference between the source and reservoir for microbes?

reservoir - where they are found the most in the natural world - can be a living habitat like a human or inatimate like soil, water, air 

source: if you got covid- the person who directly gave you it, is the source

what are the 6 types of carriers?

• symptomatic - actively shows symptoms of disease and sheds microbes

• asymptomatic

• incubation- spread during incubation (divide but no effect)

• convalescent - recuperating without symptoms (body fighting against it without having symptoms)

• chronic carrier: shelters for long period

• passive carrier: uninfected individual who picks up pathogens and transfers them to others (healthcare worker)

a live animal that transmits an infectious agent from one host to another

what are some examples?

what is the difference between one that is biological vs mechanical?

vector

majority are arthropods can also be lower vertebrates, birds

biological- actively participate in pathogen life cycle

mechanical- animal that transports microbe without being infected themselves

An infection indigenous to animals but naturally transmissible to humans (makes up 70% of emerging diseases)

Can this transmission then go on from human to human?

zoonosis

Although the INITIAL zoonosis cannot be transferred from human to human, a MUTATION of that infection can be transferred from human to human

_______ borne diseases such as malaria, dengue, west nile, yellow fever, encephilitides have killed almost half of all humans that ever lived! 

kill 700,000 people annually

mosquito 

what are DIRECT communicable ways that infectious diseases are aquired?

what are INDIRECT communicable ways that infectious diseases are aquired?

DIRECT:

1. sex (epstein-barr, ghonnorhea)

2. respiratory (cold + chickenpoxs)

3. vertical - motther to child (HIV, syphililis)

4. biological vector (west nile, malaria)

INDIRECT:

1. contaminated objects (staphylococus)

2. food, water, biologics (salmonella, e.coli)

3. droplet nuclei- dry aireborne respiratory secretions (tuberculosis, influenza)

4. aerosols: airborne animal wastes (hantavirus)

what are three forms of HEALTHCARE acquired infections?

1. nosocomial: get infection from hospital (surgical equiptment and microorganisms)

2. iatrogenic: get infection from healthcare provider

3. idiopathic : unknown source

the study of frequency and distribution of disease and health- related factors in human populations 

what is the difference between surveillances and reporting? 

epidemiology 

surveilance is collecting, analyzing, and reporting rates of occurance, mortality ,morbitity, transmission, 

report “notifiable” diseases to authorites

what is the difference between morbidity and mortality?

what is the difference between incidence and prevalence?

morbidity = proportion of population that has ILLNESS
mortality = proportion of population that DIES from illness

prevalence likelihood of having the disease AT ANY POINT IN TIME

incidence likelihood of having the disease within a CERTAIN TIME INTERVAL (number of new cases diagnosed during a particular interval of time/ population risk at the start of the interval)

what is the reproduction number (Ro)?

what does it mean if Ro>1

what does it mean if Ro <1

The number of people that an infected person infects 

Ro > 1 = disease can spread 

Ro < 1 = disease eventually dies out 

What is the dispersion factor (k)?

• Degree to which a disease _________

• The lower the value, the more the disease ______ and the number of individuals who are responsible for the ______ of the disease 

• What does it mean when k = 1

• What does it mean when k<<1

• clusters 

• clusters

• spread

• k=1 : disease is spread equally by all infected patients and is NOT clustered 

• if k is a very small number that means it mostly clusters and does not spread very far beyond local 

what was the k for influenza, what was the k for covid?

what does that mean?

k for influenza = 1 (spread widely across)

k«1

A disease that exhibits a relatively stable frequency over a long period of time in a particular geographic locale

endemic

when prevalence of a disease is increasing beyond what is expected?

epidemic

epidemic across continents 

pandemic

are generally defined as ___ or more people 

isolated cases are individual occurrences often due to pathogen entry from a _______ location

outbreak = 3+ cases

distance

What are some examples of Eukaryotic Microbes?

1. fungi

2. algae

3. protozoa

4. animals

   1. helminths

   2. arthoprods

Fungi: 

• highly ________ and MAINLY beneficial organisms

• ________ dead matter (especially plants)

• _______ relationships (plants and animals) 

• _______ production, ________ (but also spoilage) 

___________:

• occupy nearly every ecological niche on earth 

• humans inhale about 1,000 ______ everyday

___________:

• membrane-bound organelle

• sterols in the membrane 

• cell wall with ______, ______, ______, but NOT peptidoglycans

• ________ metabolism 

diverse

decomposition 

symbiotic 

food production and fermentation 

ubiquitous

spores 

eukaryotes:

• glucans, mannans, chitin, NOT peptidoglycans

• heterotrophic

what are microscopic vs macroscopic types of fungi?

microscopic = yeasts and molds

macroscopic = mushrooms

Yeasts (microscopic fungi):

• unicellular/multicellular

• filamentous/nonfilamentous

• how do they reproduce?

• can they produce spores? are the spores asexual or sexual?

• unicellular

• nonfilamentous

• asexual budding and fission + sexual mating

• spores can be asexual or sexual

Molds (microscopic yeast):

• multicellular/unicellular 

• filamentous/nonfilaments (______—> ______)

• reproduction

  • asexual and sexual reproduction

• dimorphic 

  • _______ phase/ _____ phase

  • many pathogens 

• multicellular 

• filamentous (hyphae—>mycelia)

• asexual = fragmentation of hyphae and asexual sporulation 

• sexual = sporulation 

• dimorphic 

  • mold phase/yeast phase (can be both)

  • many pathogens

Pathogenic Fungi: 

• of the millions of fungal species that exist there are about _____ are important causes of human disease 

• Over ____________ people in the US visit their doctors because of a fungal infection 

• Over ________ people in the US are hospitalized each year because of fungal infections 

• Are fungal diseases easy to treat?

• 300 

• 9,000,000

• 75,000

• NO

What are the 4 different mycoses?

• cutaneous

• subcutaneous

• systemic

• oppurtunistic

Ccutaneous Mycoses:

Caused by fungi that infect _______, _____, ______

What’s an example?

epidermis, hair, nails

dermatophytoses

Subcutaneous Mycoses: 

• Mainly from ________ fungi that live in _____ or on _________ 

• caused by implantation of _____ or ______ fragments into skin wounds 

• What are some examples? 

• saprophytic fungi soil and on plants 

• spores or mycelia

• sporotrichosis (farmers and gardeners) 

SYSTEMIC MYCOSIS (fungal disease):

• from fungi that live in the ______

• caused by _______ of spores

• typically begin in the ______ then spread 

• What are some examples? 

• soil 

• inhalation 

• lung 

• histoplasmosis and coccidiomycosis

opportunistic infections

• ____________ individuals (congenital, drug-induced, acquired disease)

what are some examples?

immunosuppressed individuals

• pneumocytosis, mucormycosis, aspergillosis, candidaisis

Algae:

• eukaryotic _______ (photosynthetucs — contain __________ with ______)

• do algae have cell walls? do they have flagella?

• esentially _______

• unicellular/multicellular

• all reproduce ASEXUALLY by ______ or ____________ of __________

• SOME can reproduce sexually

• most are located in the _________

• photoautotraughs (clorplasts with chlorophyll)

• yes have cell walls only SOME have flagela

• plants

• can be both unicellular and multicellular

• mitosis fragmentation of filaments

• most in the ocean

Algae CONTINUED: 

• produce ____% of the earth’s oxygen 

• produced most of the world’s _______ 

• important _________

RARELY pathogenic but marine ______ and ________ (saxitoxin, paralytic shellfish, poisoning, ciuatera, pfiesteria) can release potent toxins that can concentrate in and kill shellfish, fish, and marine mammales, and the HUMANS THAT EAT THEM 

80% oxygen 

most petroleum 

symbionts 

*diatoms and dinoflagellates ARE TOXIC 

Protazoa:

• Most have locomotor structures such as

• MOST are harmless living in moist habitat but SOME are spread by _____ _______

• do they have chloroplasts?

• cytopalsm is divided into _____ and ______

• feed by engulfing other ______ and _____ matter

• flagella, cillia, or psuedopodia

• insect vectors

• NO chloroplasts (heterotrophic)

• extoplasm and endoplasm

• engulf other microbes and organic matter

Pathogenic Protozoan Life Cycle:

• Trypanosoma Cruzi (Chagas DIsease)

1. vector = _________ (kissing bug)

2. transmission occcurs from ____ to ______ and ______ to vector

3. in human hosts this can lead to ____________

1. vector = reduvidd

2. vector—> mammal (cat and human) —→ vector

the bug will infect the cat, the cat will grow the protazoa and reinfect the bug

3. if this gets into humans they can also infect the bug if it bites the humans

if humans get bitten they experience fever, inflamation, heart and brain damage… death

Parasitic Helminths:

unicellular/multicellular animals

do they have organs?

do they have eggs and sperm?

_____ _______ go through larval period in or out of host body

NOT RLLY MICROBES

• multicellular

• yes they have organs for reproduction, digestion, movement, protection

• they DO have eggs and sperm

• fertilized eggs —> larval period IN or OUT of host

Parasitic Worms:

how do you get them?

how many species can parasitize humans?

examples: ascariasis, hookworm, filariasis, schistosomiasis

eat egg or larvae through food, water, soil, insect vectors

50 species

what are the two major groups of parasitic worms?

what are some examples of each? 

1. flatworms (cestodes-tapeworms and trematodes-flukes)

2. roundworms (nematodes)

Which structures do flatworms (cestodes- tapeworms and trematodes) have?

• digestive tract

• blind pouch

• excretory system

• nervous systems

Which structures do roundworms (nematodes) have?

• complete digestive tract

• protective surface cuticle

• spines and hooks on mouth

• excretory system

• nervous system

Arthropods:

• ______ and _____ legs

• many must feed on blood and tissue fluid of host during life cycle (_________)

• LARGEST _______ (over 1 million species)

NOT MICROBES but have importance as

• bilogical _______

• trasmit microbial diseases caused by _______, _______, _______, _______, and _________.

exoskeleton and jointed legs

ectoparasites

phylum

transmit diseases caused by

• viruses

• bacteria

• rickettsia

• protozoa 

• nematodes

Mosquitos:

• require ______ habitat

• do females or males take blood meal transmitting disease?

• what are some examples?

• aquatic

• females transmit diseases

• dengue, malaria, filariasis

Fleas:

• highly _______with _____ bodies

• feed on ____-blooded animals

• carry ______ diseases such as ______ and ______ ________

• motile with flattened

• warm

• zoonotic - plague, murine typhus

Lice: 

_________ feed on blood and tissue fluid 

release _____ that contaminate the womb 

what are some examples? 

inconspicuously 

feces 

Epidemic typhus (releases rickettsia in feces, which humans can bring into the body through itching eyes and scratching), relapsing fever

Ticks:

• a type of ________

• cling on _______ and attach to host on contact

• _____, ______, AND _____ get blood meal by piercing skin or host

• hard or _____ ticks — small compact, ridgit bodies transmit _______, ______, and _____ diseases

• soft of ______ ticks- flexible outer bodies trasnmit _______ ______

• arachnid

• vegetation

• larvae, nymph AND adults

• ioxodid = hard = transmit bacterial, rickettsial and viral diseases

• argasid = soft = trasmit relapsing fever