microbio exam 02 infections

conjunctivitis (pink eye)

• bacterial infection of upper respiratory system

• inflammation of eye surfact

• S/S: redness, swelling, pus, tearing, light sensitivity

• T/P: antibiotics, highly contagious (hygiene + isolation)

otitis media (middle ear infection)

• bacterial infection of upper respiratory system

• fluid trapped behind ear drum

• S/S: severe ear pain, fever, irritability, possible hearing loss

• T/P: antibiotics, flu vaccine reduces risk

sinusitis

• bacterial infection of upper respiratory system

• inflammation of sinuses

• S/S: facial pain/pressure, headache, thick nasal discharge

• T/P: antibiotics, flu vaccine reduces risk

streptococcal pharyngitis (strep throat)

• bacterial infection of upper respiratory system

• S/S: sore throat, fever, difficulty swallowing, red throat with pus spots, swollen/tender lymph nodes, no cough/runny nose

• CA: streptococcus pyrogens

• EPI: spread by respiratory droplets, asymptomatic carriers, common in 5-15yo

• T/P: strep test + culture, penicillin, no vaccine, avoid crowding

acute rheumatic fever

• bacterial infection of upper repiratory system

• occurs ~3week after strep infection

• caused by autoimmune cross reaction

• S/S: fever, joint pain, rash, nodules, heart inflammation, involuntary movements (chorea)

post-streptococcal glomerulonephritis

• bacterial infection of upper respiratory system

• occurs 1-3 weeks after strep infection

• S/S: blood/protein urine, swelling, high blood pressure

diphtheria

• bacterial infection of upper respiratory system

• S/S: mild sore throat, slight fever, severe fatigue, swollen neck

• CA: corynebacterium diphtheriae (gram-pos rod)

• EPI: humans = only reservoir, spread via respiratory droplets/formites

• T/P: antibiotics, vaccination, immediate antitoxin required

common cold

• viral infections of upper respiratory system

• S/S: malaise, runny nose, sneezing, coughing, mild sore throat, fever (rare), hoarseness, nasal secretion, last ~1week

• CA: rhinoviruses (non-enveloped)

• PATH: infect nasal epithelial cells → cause cell damage → spread to sinuses/lower respiratory tract

• EPI: spread via airborne droplets/contaminated hands (close contact), human = only reservoir

• T/P: no cure/vaccine, antibiotics don’t work, handwashing

adenovirus respiratory infections

• viral infections of upper respiratory infections

• S/S: sore throat, runny nose, fever, gray-white patches on tonsils, swollen lymph nodes, mild cough, 1-3 weeks

• CA: adenoviruses (nonenveloped, destroyed by heat/disinfectants)

• PATH: infect epithelial cells → viral DNA enters nucleus and replicates → cell destruction → inflammation + tissue damage

• EPI: spread via respiratory droplets/formites/fecal-oral route, persist in enviornments for long periods, outbreaks in schools

• T/P: antibiotics for secondary bacterial infections, hygiene

pertussis (whooping cough)

• bacterial infections of lower respiratory system

• 3 stages… catarrhal (mild cold-like symptoms), paroxymal (severe whooping coughing fits), convalescnet (recovery)

• cause berdetella pertussis

• EPI: contagious

pneumococcal pneumonia

• bacterial infections of lower respiratory system

• S/S: rust colored/blood tinged sputum, fever + chills, chest pains, rapid shallow breathing, cyanosis (low O2)

• CA: streptococcus pneumoniae

• PATH: capsule prevents phagocytosis

• T/P: vaccine and antibiotics (penicillin)

klebsiella pneumonia

• bacterial infections of lower respiratory system

• S/S: thick/jelly-like bloody sputum, fever, cough, chest pain, cyanosis

• CA: klebsiella pneumoniae (gram-neg)

• PATH: capsule prevents phagocytosis

• EPI: common in hospitals, increasing antibiotic resistance, alcoholics

• T/P: antibiotics, may require surgery for abscess

mycoplasmal pneumonia (walking pneumonia)

• bacterial infections of lower respiratory system

• S/S: mild pneumonia, sore throat, fever, fatigue, dry cough

• CA: mycoplasmal pneumonia (no cell wall/slow growing)

• PATH: attaches to ciliated respiratory cells → evades mucociliary clearance → damages epithelium → inflammation

• EPI: spread by aersolized droplets, shed a week before symptoms

tuberculosis (TB)

• bacterial infections of lower respiratory system

• S/S: night sweats, cough with blood sputum, weight loss, fever,

• CA: mycobacterium tuberculosis (slow growing)

• EPI: spread via airborne droplets, require few bacteria

• T/P: long term combination antibiotics, vaccine

legionnaires disease

• bacterial infections of lower respiratory system

• S/S: fever, chills, headache, confusion, dry cough w/ sputum, shortness of breath

• CA: legionella pneumophila (gram neg)

• EPI: widespread in warm natural waters/AC systems

inhalation anthrax

• bacterial infections of lower respiratory system

• S/S: flu-like symptoms for 1-2 weeks (fever/cough), then severe respiratory distress

• CA: bacillus anthracis (resistant spore, gram pos rod)

• EPI: zoonotic (livestock exposure) → ppl working with animals

• T/P: antibiotics, antitoxin therapy, vaccine available

influenza

• viral infection of lower respiratory system

• A (most severe, human disease), B (human disease), C, D types

• S/S: fever, headache, muscle aches, sore throat, fatigue

• CA: enveloped ssRNA virus

• PATH: spread via droplets/formites, destroys mucociliary escalator

• EPI: small % fatal and epidemics are annual, close contact

• T/P: no antibiotics, antivirals, annual vaccines

respiratory syncytial virus (RSV)

• viral infection of lower respiratory system

• S/S: runny nose w/ fever/coughing/wheezing, difficulty breathing, bad cold if older child/adult

• CA: enveloped ssRNA, paramyxovirus

• PATH: infects respiratory tract epithelium

• EPI: late fall to late spring, worse in younger kids/older adults, infected by 2yo, reinfection common

• T/P: no antiviral or vaccines

coronaviruses (COVID-19/SARS/MERS)

• viral infection of lower respiratory tract

• S/S: flu-like symptoms (fever/cough), nonproductive cough, may develop pneumonia

• CA: SARS-CoV-2 → COVID-19, SARS-CoV → SARS, MERS-CoV → MERS, enveloped ssRNA viruses with spike proteins

• PATH: spike proteins bind to host cells → replicate in lower respiratory tract → viral RNA hidden in vesicles to avoid detection

• EPI: zoonotic viruses (likely originated in bats), spread via respiratory droplets

• T/P: no universal care, supportive care (O2/ventilation), handwashing

hantavirus pulmonary syndrome (HPS)

• viral infections of lower respiratory tract

• S/S: fever, muscle aches (in lower back), fatigue, nausea, diarrhea, unproductive cough

• CA: hantavirus

• PATH: inhaled from contaminated dust → infect lung capillaries → leakage, fluid fills lungs → suffocation → shock

• EPI: linked to rodent exposure/poor ventilation

• T/P: no antiviral, avoid rodent exposure, proper cleaning

coccidioidmycosis (valley fever)

• fungal infection of lower repiratory system

• S/S: flu-like symptoms (fever, cough, chest pain), loss of apettite/weight, joint pain, rash, painful nodules, night sweats

• CA: coccidioides immitis

• PATH: inhaled anthroconidia that mature and rupture endospores

• EPI: dry/dusty climates, in southwest of U.S., farm/construction workers at risk

• T/P: antifungal medications, avoid dust exposure

histoplasmosis (spelunker’s disease)

• fungal infection of lower respiratory system

• usually benign but can mimic TB

• S/S: asymptomatic

• CA: histoplasmosis capsulatum

• PATH: inhaled → grow inside macrophages → spreads, forms granulomas

• EPI: in tropical/temperate zones in the world, associated with bird/bat droppings, cave explorers/farmers/construction workers at risk

• T/P: antifungal medications, avoid contaminated soils

pneumocystis pneumonia (PCP), no need…

• fungal infection of lower respiratory system

• S/S: gradual fever/shortness of breath/dry cough

• CA: pneumocystis jirocevii (yeast-like fungus)

• PATH: inhaled → attach to alveoli → inflammation/fluid/organism buildup in alveoli → thickened alveolar walls and impaired O2 exchange

• EPI: worldwide distribution, spread airborne

• T/P: drugs, isolation in hospitals

hair follicle infections

• bacterial diseases of skin

• S/S: folliculitis (inflammation) causes red bumps (pimples), infection lead to boil

• CA: staphylococcus aureus

• PATH: attach to follicles → spread to sebaceous glands → excrete toxins → damage/kill host cells

• EPI: common in nostrils, easy to transmit on fomites

• T/P: minor surgery on boils, antibiotics (although resistant to many antibiotics)

staphylococcus scalded skin syndrome (SSSS)

• bacterial disease of the skin

• S/S: skin looks burned (blisters/peeling), fluid loss, painful

• CA: staphylococcus aureus

• PATH: epidermis splits below dead layer, toxins spread thru bloodstream

• EPI: any age but frequent to newborns, airborne

• T/P: antibiotics, dead skin removal, rehydration

impetigo

• bacterial infection of skin

• most common pyoderma (skin infection w/ pus production)

• non-bullous (brusted yellow leisions) or bullous (large blisters)

• S/S: patches of inflammation, thin walled blisters that develop/break and replaced by drying plasma

• CA: staphylococcus aureus/streptococcus pyrogens → non-bullous, staphylococcus aureus that produce toxins → bullous

• PATH: minor injuries introduce bacteria on superficial skin layers into deeper skin layers

• EPI: common in young children in humid areas, airborne, insects/fomites spread

• T/P: topical/oral antibiotics, clean

rocky mountain spotted fever (RMSF)

• bacterial infection of skin

• S/S: rash starts on wrists/ankles and spreads, fever, headache

• CA: rickettsia rickettsi

• PATH: transmitted by tick bite → bacteria multiply within cells, infect blood vessels

• T/P: doxycycline, no vaccine, tick prevention

cutaneous anthrax

• bacterial infection of skin

• S/S: papule → blister → black ulcers

• CA: bacillus anthracis

• PATH: produce toxins that disrupt cell signaling pathways

• EPI: animal workers, not airborne

• T/P: antibiotics

varicella (chickenpox)

• viral infection of skin

• S/S: rash, small red bumps → little bumps → small blisters, fever, headache, malaise

• CA: varicella-zoster virus of herpesviridae

• PATH: enters respiratory → replicated in lymph nodes → tavel to skin via bloodstream

• EPI: highly contagious, transmitted by respiratory secretion/skin lesions, more severe in adults, humans = only reservoir

• T/P: antivirals, vaccines

rubeola (measles)

• viral infection of skin

• almost gone (due to vaccine)

• S/S: koplik spots, fever, runny nose, red eyes, maculopapular rash on face, secondary infections can occur

• CA: rubeola virus

• PATH: enters respiratory → spreads to lymphatic tissues

• EPI: humans = only natural host

• T/P: MMR vaccine

rubella (german measles)

• viral infection of skin

• dangerous in pregnancy

• S/S: slight fever, swollen lymph nodes, faint pink rash

• CA: rubella virus

• PATH: entry via respiratory → move to lymph nodes → enter blood stream

• EPI: humans = only natual host, highly contagious from week before and after rash

• T/P: MMR vaccine

warts

• viral disease of skin

• CA: human papillomavirus

• PATH: infect skin via minor abrasions

• T/P: freezing, burning, cutting off

superficial cutaneous mycoses

• fungal disease of skin

• S/S: ringworm, itching, odor, rash, scalp infection

• CA: dermatophytes

• PATH: infect keratinized tissues (skin/hair/nails) → produce keratinase → breaks down keratin for nutrients

• EPI: prefer warm/moist environments, common/sever in children

• T/P: topical antifungals, keep clean/dry

staphylococcal wound infections

• bacterial infections of wounds

• S/S: pus formation (pyrogenic), inflammatory response (redness/swelling/pain)

• CA: staphylococcus aureus, staphylococcus epidermis

• PATH: lots of factors play a role in wound infections…

• EPI: s.aureus inc risk for surgical wound infection, s.epi usually part of normal microbiota

• T/P: resistant to antibiotics, cleaning

streptococcus pyrogens

• bacterial infection in wounds

• S/S: severe pain, rapid swelling/discoloration, fever, confusion, progress within hours

• PATH: enzymes destroy tissue

• T/P: IV antibiotics + supportive care, surgical debridement, medical emergency

pseudomonas aeruginosa

• bacterial infections of wounds

• S/S: green pus, skin lesions, chills

• EPI: widespread in nature, grows in places with moisture

• T/P: resistant to many antibiotics (has biofilms)

tetanus (lockjaw)

• disease due to anaerobic bacterial wound infection

• S/S: muscle spasms (starts in jaw), difficulty swallowing, irritability

• CA: clostridium tetani

• PATH: bacteria localized in wound → produces toxin that travels thru nerves → blocks inhibitory neurons → muscles can’t relax

• EPI: widespread in dirt/dust/rusty stuff

• T/P: TIG injection, vaccine, antibacterial medication

clostridial myonecrosis (gas gangrene)

• disease due to anaerobic bacterial wound infection

• S/S: severe pain, swelling, fluid from wound, gas bubbles, black skin, rapid onset

• PATH: presence in dirt and dead tissue in wound

• EPI: found in dirt

• T/P: cleaning/removal of tissue, antibiotics

pasturella multocida (bite)

• bacterial infection of bite wound

• S/S: spreading redness, tenderness, swelling, pus discharge, leads to meningitis

• CA: pasteurella multocida

• PATH: some strains produce toxins

• EPI: many humans/animals carry pasturella multocida

• T/P: penicillin

bartonellosis (cat scratch disease)

• bacterial infection of bite wound

• S/S: pus filled pimple within a week of scratch/bite, lymph nodes enlarged and may be pus filled, fever, fatigue

• CA: bartonella henselae

• EPI: worldwide, zoonosis of cats only

• T/P: antiseptic, avoid stray cats

sporotrichosis (rose gardener’s disease)

• fungal wound infection

• S/S: resemble bacterial skin infection, small/painless bump (pimple) → chronic ulcers

• PATH: injury caused by plant material enter body, spread along lymphatic vessels

• EPI: more common in warm climates, farmers/gardeners at risk, animals can transmit

• T/P: proper wound care

dental caries (tooth decay/cavities)

• bacterial diseases of upper digestive system

• S/S: discoloration, roughness, toothache

• CA: streptococcus mutans (produce acid and survives acidic conditions)

• PATH: acids from bacteria grow on teeth, plaque forms biofilms

• EPI: worldwide

• T/P: fill cavities, root canal, brush/floss regularly, fluoride strengthens enamel

periodontal disease

• bacterial infection of upper digestive system

• infection and inflammation around gums/teeth, includes gingivitis/chronic periodontitis

• CA: polymicrobe infection

• EPI: smokers increased

• T/P: cleaning, antibiotics

gingivitis

• bacterial disease of upper respiratory system

• S/S: red swollen gums, tender gums, bleeding gums

• CA: plaque buildup near gum line

• T/P: plaque removal, brush/floss

chronic periodontitis

• bacterial infection of upper digestive disease

• S/S: bad breath, bleeding gums, gum recession, loose teeth, tooth loss

• CA: anaerobic gram neg bacteria

• T/P: plaque/tartar removal, antibiotica aavailable

acute necrotizin ulcerative gingivitis (ANUG/trench mouth)

• bacterial infection of upper digestive system

• S/S: bleeding/painful gums, often ulcerated, bad brath, metallic taste

• CA: anaerobic poymicrobial infection at gum line

• EPI: bad oral hygiene, high sugar diet

• T/P: hydrogen peroxide, antibiotics, brushing

helicobacter pylori gastritis (stomach ulcers)

• bacterial infections of upper respiratory system

• S/S: often asymptomatic, possible burping, bloating, nausea, loss of appetite, black stool

• CA: helicobacter pylori (curved gram neg w/ flagella)

• PATH: h.pylori survives acidic environment by converting close acid to alkaline to neutralize acid, burrows into stomach mucus layer and attach to epithelial cells

• EPI: common with older age

• T/P: antibiotics, acid reducing medication

oral herpes (cold sores

• viral diseases of upper digestive system

• S/S: small blisters in mouth, recurrent cold sores usually less severe

• CA: herpes simplex viruses (HSV-1 for oral, HSV-2 for genital)

• PATH: virus multiplies in epithelium → destroys cells

• EPI: worldwide, close contact/saliva/fomites and can infect almost any body tissue

• T/P: antivirals, sunscreen

mumps

• viral disease of upper digestive system

• S/S: painful swollen parotid glands, difficulty chewing/talking, loss of appetitie, possible meningitis

• CA: mumps virus

• PATH: inhaled thru saliva droplets and spread thru bloodstream

• EPI: humans = natural host, lifelong immunity after recovery

• T/P: MMR vaccine, no antiviral treatment

cholera

• bacterial diseases of lower digestive system

• S/S: sudden onset of severe watery diarrhea, vommiting, muscle cramps, can cause death within hours (due to dehydration)

• CA: vibrio cholerae (curved gram neg rod)

• PATH: needs a lot to infect people (bc stomach acid kills many bacteria)

• EPI: fecally contaminated water

• T/P: rapid replacement of fluid/electrolytes, clean area

gastroenteritis (stomach flu)

• bacterial disease of lower digestive system

• S/S: diarrhea, nausea, vomiting, small intestine watery diarrhea, large intestine has mucus/pus/blood in diarrhea

• PATH: horizontal transfer and exotoxins

• EPI: fecal-oral route

• T/P: oral rehydration therapy, clean areas