micro test 4

what kind of defense is the skin

barrier defense

what are the chemical defenses of the skin

• oils

• sweat (low ph, high salt content)

how is the epidermis a defense for the skin

its keratinized and it is constantly sloughing off cells

Parenteral

entering the body by a route other than the digestive tract (not swallowing or eating).

• Injections (needle)

• Contaminated blood entering the bloodstream

• Needlestick injuries

possible causative agents, most common modes of transmission, and prevention for MRSA

• methicillin-resistant staphylococcus aureus

• direct and indirect contact

• hygiene practices

possible causative agents, most common modes of transmission, and prevention for impetigo

• staph aureus and streptococcus pyogenous (causes strep)

• both direct and indirect

• both hygiene practices

possible causative agents, most common modes of transmission, and prevention for cellulitis

• MRSA, strep pyogenes, other bacteria/fungi

• parenteral implantation

• no prevention

possible causative agents, most common modes of transmission, and prevention for staphylococcal scalded skin syndrome (SSSS)

• staph aureus

• direct and droplet contact

• eliminate carriers in contact with neonates

  • remove or treat people who carry an infectious disease and could spread it to newborn babies.

possible causative agents, most common modes of transmission, and prevention for gas gangrene

• clostridium perfringens and other bacteria

• vehicle (soil), endogenous, transfer from skin, GI tract

• clean wounds, debride dead tissue

what are the 3 vesicular and pustular rash disease

• chicken pox

• small pox

• HFMD - hands foot and mouth disease

what is the causative organism, most common mode of transmison, and prevention for chicken pox

• varicella-zoster virus

• droplet contact, inhalation of aerosolized lesion fluid (breathing in tiny particles of infected fluid that come from someone's blisters or skin sores)

• live attenuated virus; also, a vaccine to prevent reactivation of latent virus (shingles)

what is the causative organism, common mode of transmission, and prevention for smallpox

• variola virus

• droplet and indirect contact

• jynneos vaccine and ACAM 2000, Vaccine virus used for immunization

what is the causative organism, common mode of transmission, and prevention for hand foot and mouth disease

• coxsackie virus

• direct and droplet contact

• hand hygeine

what age is HFMD most common in

babies and children < 5 yo

what are the 5 macuoppaular rash diseases

• measles

• rubella

• fifth disease

• roseola

what is the causative organism, common mode of transmission, and prevention for measles (rubeola)

• measles virus (they are flat and slightly raised)

• droplet contact

• live attentued virus (MMR or MMRV)

what is the only reservoir for measles

humans

what is the causative organism, common mode of transmission, and prevention for rubella “little red”

• rubella virus

• droplet contact

• live atteunted vaccine (MMR or MMRV)

what is rubella also known as

german measles

what two forms does rubella come in

• postnatal infection (children / adults)

• congenital infection

  • an infection that a baby gets from their mother during pregnancy, before birth.

what is the causative organism, common mode of transmission, and prevention for fifth disease (erythema infectiousum)

• marked out on notes

• droplet contact: very contagious

• no prevention

what is the causative organism, common mode of transmission, and prevention for roseola (6th disease)

• marked out

• unknown

• none

roseola is most common in

young children and babies

if you get the roseola virus you may or may not get what, but it does come with

a rash, a high fever

on the 4th day of roseola your fever disappears but what might appear

rash

what rash is believed that 100% of the populaton is exposed to this disease at some point in their life

roseola

what are the 2 causative organisms for wartlike eruptions

• human papilloma viruses

• molluscum contagiosum viruses

what is the mode of transmission for human papilloma virus

• direct contact, autoinoculation (spreading an infection to another part of your own body), indirect contact

what is the mode of transmission for molluscum contagiosum viruses

• direct contact, including sexual contact, and autoinculation

what is the prevention for human papilloma viruses and molluscum contagiosum viruses

avoid contact

in what region of the world does molluscum contagisum warts have the highest incidence

pacific islands

• found in children, adults, and immunocomprimsed (milky fluid)

what are the 2 diseass associated with large pustular skin lesions

• leishmanisasis

• cutaneous anthrax

what is the causative organism, common mode of transmission, and prevention for leishmaniasis

• leishmania spp

• biological vector

• avoid sand fly

how is leishmaniasis transmitted

by a female sand fly

• protozoan inside of the fly; sand fly bites human

what is the causative organism, common mode of transmission, and prevention for cutaneous anthrax

• bacillus anthracis (most common and least dangerous)

• direct contact with endospores (comes in through a cut)

• avoid contact; vaccine available but not widely used

what is an important feature that forms on your skin when you have cutaneous anthrax

a black eschar

List the skin conditions for which vaccination is recommended.

• chicken pox

• smallpox

• measles

• rubella

what is ringworm of the scalp

tinea capitis

what is ringworm of the beard

tinea barbae

what is ringworm of the body

tinea corporis

what is ringworm of the groin

tinea cruris

what is ringworm of the foot

tinea pedis

what is ringworm of the nail

tinea unguim

what does MRSA stand for, and what does this mean

Methicillin-Resistant Staphylococcus aureus

• a type of bacteria that is resistant to the antibiotic methicillin + a lot of others

• can survive dry environments, resistant to salt, can be left on countertops for a while

Discuss the relative dangers of rubella and rubeola (mesales) viruses in different populations.

rubella

• Especially dangerous to baibes during pregnancy because it can harm the developing baby.

• cause a cogenital infection→ teratogenic virus→ birth defects

rubeola (measles)

• children

• begins with fever, sore throat, headache, oral lesions and maculopapular lesions

what are the 2 exposed surfaces of the eye

• conjunctiva

• cornea

what is the cinjunctiva

a thin membrane like tissue that covers the eye (not the cornea) and lines the eyelids

what is the cornea

the domed shaped central portion of the eye lying over the iris

what are the defenses of the eye

blinking and tears

what are the two antimicrobial enzymes in the tears that help prevent bacterial infections

• lysozyme: Breaks down bacterial cell walls, killing bacteria.

• lactoferrin: Binds to iron so bacteria cannot use it to grow.

the eye has Immune privilege, what does that mean?

the eye limits inflammation and immune responses to prevent damage that could affect vision

what disease is conjunctivitis most commonly known as

pink eye

what are the 3 conjunctivits diseases

• neonatal

• bacterial

• viral

what is the causative organism, common mode of transmission, and prevention for neontal conjunctivitis

• chlamydia trachomatis and Neisseria gonorrhoeae

• vertical (mother to baby; often in vagina)

• screen mothers and apply antibiotic to newborn eye

what is the common mode of transmission, and prevention for bacterial conjunctivitis

• direct and indirect contact

• hygiene

what is the causative organism, common mode of transmission, and prevention for viral conjunctivitis

• adenoviruses

• direct, indirect contact

• hygiene

what is the causative organism, common mode of transmission, and prevention for trachoma (eye)

• chlamydia trachomatis

• indirect contact and mechanical vector

• hygiene, vector control, prompt treatment of initial infection (antibitoics are effective)

  • - Vector control: Controlling insects or animals, such as mosquitoes and ticks, that carry and spread diseases. Example: spraying to kill mosquitoes.

    - Prompt treatment of initial infection: Treating an infection as soon as possible to prevent it from getting worse or spreading to others.

there are few cases of trachoma in the US but millions in what 2 places

africa and asia

is keratitis a more serious infection? what is it

yes it is the scarring of the cornea

what are the 2 causative organism for keratitis (eye)

herpes simplex virus and miscellaneous microogrnaism including Acanthamoeba

what are the most common modes of transmission and prevention for herpes simplex virus

• reactiation of latent virus, primary infections can occur in the eye

• no prevention

what are the most common modes of transmission and prevention for miscellaneous microogrnaism including Acanthamoeba

• traumatic introduction→ parenteral (a pathogen enters the body through an injury or break in the skin)

• no prevention

what is important about herpes simplex virus

its the leading cause of blindness in the US

where is acanthamoeba found

in lakes and tap water, issues with dirty contact

what kind of infection is river blindness

a chonric parasitic (helminthic→ worms) infection

what is the causative organism, common mode of transmission, and prevention for river blindness

• walbachia and onchocerca volvulus

• biological vector

• avoiding black fly

Wolbachia bacteria lives in a mutualistic relationship with the

worm

Discuss why there are distinct differential diagnoses for neonatal and non-neonatal conjunctivitis.

Neonatal conjunctivitis has different possible causes because newborns can get infections from their mothers during childbirth, while older children and adults usually get it from everyday exposure to viruses or bacteria.

what are the 2 componets of the nervous system

CNS

• brain and spinal cord

PNS

• peripeheral nerves

what are the nervous systems natural defenses

• cushion of cerebrospinal fluid

• meninges that surround the brain and spinal cord

• blood brain barrier

cerebrospinal fluid is found in what space in the brain

subarachnoid space

similar to the eye the brain is also a _______ privileged site

immunologically

Discuss the current state of knowledge regarding the normal biota of the nervous system

the nervous system has no normal biota

• any microorganism found in the CNS or PNS is considered abnormal and a sign of a possible infection, because the nervous system normally does not have resident biota.

what is meningitis an inflammation of

meninges

what is encephalitis an inflammtion of

the brain

what is meningoencephaltiis an inflammtion of

both the menegies and encephalitis

what is the defining symptom of meningitis

can you touch your chin to your chest?

which causative organism of menegitis do we worry about the most

neisseria meningitdis

what are the caustaive agents of meneigtis

• neisseria meningitdis

• streptococcus pneumoniea

• haemophilus influenzae

• listeria monocytogenes

• crytpococcus neoformans

• coccidiodes

• viruses

which of the meningitis causative organisms, most common mode of transmission “droplet contact”

• neisseria meningitdis

• streptococcus pneumoniea

• haemophilus influenzae

• viruses

which of the meningitis causative organisms, most common mode of transmission “vehicle”

• listeria monocytogenes (food)

• crytpococcus neoformans (air, dust)

• coccidiodes (air, dust, soil)

prevention for neisseria meningitdis

conjugated vaccine; ciproflaxin, ridampin, ceftriaxone used to protect contacts

prevention for streptococcus pneumoniea

two vaccines

• prevnar (adults and children)

• pheumovax (adults)

prevention for haemophilus influenzae

Hib vaccine, ciproflaxxin, rifampin, ceftriaxone

prevention for listeria monocytogenes

cooking food, avoiding unpasteurized dairy products

prevention for coccidides

avoiding airborne endospores

what is the tell tale sign for Neisseria meningitidis (aka meningococcus)

petechiae

• hemorrhaged blood appears as streaks/red blotches

which of the causative organisms is most the most frequent cause of community acquired meningitis

streptococcus pneumoniae

what is different about Neisseria and streptococcus pneumoniae

strepto doesn’t cause the petechiae

haemophilus influenza was though to cause what

what is it sensitive to?

the flu

• drying, temperature extremes, and disinfectants

• causes severe meningitis

listeria monocytogenes is found where

basically everywhere

• food gets recalled bc of this organism

listeria monocytogenes in pregnant women usually results in

premature abortion and fetal death

• why doctors say not to eat processed meat while pregnant

cryptococcus neoformans is different than the rest of the causative agents of meningitis because

it is a fungus

what is the primary niche of cryptococcus neoformans

bird populations (pigeons) (pigeon lady)

• more chronic form

what is special about coccidioides immitis

it is dimorphic

• fungus grows as a

  • Mold: At cooler temperatures.

  • Yeast: At body temperature.

it’s a fungus

its found in dirt not pigeons

where is coccidioides immitis most common in

soil, spread by wind and animals

how to prevent coccidioides immitis

• oil dirt roads

• wear a mask while excavating dirt

• planting vegetation

does only 1 virus cause viral meningitis

no, many diff viruses can cause it

aseptic meningitis

what are the 4 causative organisms for neonatal and infant meningitis

• streptococcus agalactiae

• e coli strain K1

• listeria monocytogenes

• cronobacter sakazakii

mode of transmission and prevention for streptococcus agalactiae (neonatal/infant meningitis)

• vertical (during birth)

• culture and treatment of the mother