Gram Negatives

What are the 2 gram negative cocci

• Neisseria

• Gonorrhea

Neisseria 2 morphology characteristics

• Gram-neg diplococci

• coffee-bean shaped ☕🫘

Where is Neisseria found

In mammal’s mucous membranes

What are the 2 Neisseria pathogenic strains?

• N. gonorrhoeae

• N. meningitidis (meningicoccal)

2 Portals of entry N. gonorrhoeae vs N. meningitidis

• N. gonorrhoeae – genitourinary tract

• N. Meningitidis - respiratory tract

How does N. Meningitis enter resp tract? What does it produce?

• using Aerosol

• produces Endotoxins

What type of disease does Gonorrhea cause

STIs

Define incubation & how long for Gonorhea

• time from exposure to pathogen to first appearence of symptoms

• few days

Function of fimbriae in Gonorrhea?

they attach to columnar epithelial cells

What causes Gonorhea pus formation?

Leukocyte infiltration (inflammation)

What does untreated gonorrhea cause?

endocarditis & arthritis (1%)

Gonorrhea: Ophtalmia Neonatorum

infects infant eyes → blindness

Gonorrhea: Pharyngeal gonorrhea:

like septic sore throat

Gonorrhea: anal

itching/pain/pus.

Vaccines protect against which meningococcal gonorrhea serotypes?

serotypes A, C, Y and W-, 135

What is used in gonnorhea vaccine?

purified polysaccharides (made remotely)

What are the 3 negative aerobic bacilli?

• Brucella

• Pseudomonas

• Bordetella

Brucella 4 morphology characteristics

• gram neg coccobacilli 🥥

• aerobic

• small

• non motile

Brucella is an obligate parasite only of _

mammals

What disease does brucella cause (+aka)

Brucellosis *aka undulant fever

What is the reservoir of Brucella & what it causes

domestic livestock → abortions

Brucella 3 transmissions

• contaminated milk, meat, & animals

Brucella was reported as _ in what year

2008 Nationally notifiable infectious disease (NNID)

How many new cases of Brucella annually

500k (less fatal)

How does Brucella relate to economics?

affects developing world economics bc animals x_x

What is the world’s most common bacterial zoonosis?

Brucellosis

6 Regions where brucellosis is endemic?

• Southeast Europe

• Middle East

• Mediterranean

• Asia

• Latin America

• Caribbean

What can brucella survive? Where can it perssit?

• Phagocytosis by macrophages PMNS

• reticuloendothelial system

Brucella actions

• Evades host defenses →

• long-term survival →

• chronic disease →

• multi-organ effects

3 reasons why Brucella a bioterrorism concern?

• bc easily airborne, dangerous to handle, & requires BSL-4

What are the 3 Brucella species?

• B. abortus

• B. suis

• B. melitensis

Who does B. abortus affect?

• cattle, camels, bison

Who does B. suis affect?

• swine & cattle if they’re close

Who does B. melitensis affect?

• most serious cases in humans

• +sheep/goats 🐑

What brucellosis species formerly caused most U.S. human cases? What changed that?

• B. abortus (now rare)

• Cattle vaccination eliminated it

• What brucellosis species now causes most U.S. cases?

• What group of ppl & why?

• B. melitensis → hispanics

• Mexico imports of unpasteurized soft cheese/goat milk

Brucella incubation period

1-3 weeks+

Symptoms of Brucellosis

• rise/fall fever (undulant fever)

• malaise

• muscle aches

• night sweats

What kind of definitive test tests for Brucella & what it does

Serological test: isolates blood/tissue

First step in diagnosis of Brucella

ask patient if exposed to endemic areas

Does Brucella have antibiotic resistance?

no, none reported

Pseudomona 4 morphology characteristics

• gram neg bacilli

• aerobic

• polar flagella

• twitching motility rods

Where are Pseudomonas commonly found

soil & other natural enviro

• What do Pseudomonas cause?

• in what 2 patient groups?

• 1 in 10 nosocomial infections in hospitals

• burn & cystic fibrosis patients

Pseudomona syringae is an occasional _

plant pathogen

What does Pseudomona aeruginosa produce?

soluble blue/green colonies

Pseudomona aeruginosa 6 portals of entry

• infects urinary tract

• burns

• wounds

• sepsis (blood infec)

• abscesses

• meningitis

What 3 roles does Pseudomonas aeruginosa play in bioremediation?

• breaks down pollutants

• synthesizes MANY enzymes

• metabolizes variety of substrates

Pseudomona aeruginosa has the genetic capacity of _

eukaryotic yeast

Why can P. aeruginosa cause chronic infections?

Forms biofilms that resist immune response.

P. aeruginosa can grow in what medical devices

catheters & implants

What disease is heavily impacted by Pseudomonas biofilms?

Cystic fibrosis lung infections → death

What unusual carbon sources can Pseudomonas grow on?

• soap residues

• adhesives

• antiseptics (quats)

What kind of temp can Pseudomonas grow on & what they cause

• refrigerator temps →

• food spoilage

How do Pseudomonas affect soil nitrogen?

Converts nitrate → nitrogen gas → loss of fertilizer nitrogen.

2 reasons why Pseudomonas highly drug-resistant?

• large genomes code for efflux pumps to eject em out cells

• porins block entrance

Bordetella 4 morphology characteristics

• gram neg coccobacilli 🥥

• obligate aerobes 

• non motile

• Virulent Strain has capsules 

What disease does B. pertussis cause?

pertussis aka whooping cough

What was B. pertussis classified as & when

emerging infectious disease (2000)

How does B. pertussis cause disease?

attaches to trachea’s ciliated cells (impedes then destroys cells)

When B. petussis attatches to trachea cillia cells, what does it prevent?

ciliary escalator sys from clearing mucus 🤧

Dropplet transmission:

• type of transmission

• what travels & how far → airborne?

• when discharged

• contact

• droplet nuclei (mucous) travel short dist (1 meter) → not airborne

• air, coughing, sneezing, laughing/ talking

• How long are droplet transmissions incubated for?

• Whats the portal of entry?

• 6-14 days

• GI tract

2 kinds of vaccines available for B. pertussis

• Whole cell

• acellular

B. pertussis vaccine for children when?

• b4 school

• boosters in ages 10-18yo

Francisella morphology 3 characteristics

• gram neg baccilus

• small

• pleomorphic

Where does Francisella grow only on?

complex media enriched w blood/tissue extract 

• What disease does Francisella cause?

• Where does this name come from?

•  Tulameia

• Tulare county CA (first observed) 

Tulameia is a king of _ disease

Zoonic

Francisella’s Tulameia is also known as what other 4 names?

• Pahvant Valley plage

• Rabbits/rodents Fever

• Deer fly fever

• Ohara’s fever

How does F. tularensis route of entry & what it causes?

skin → ulcers

F. tularensis symptom after 1 week

swollen/pus lymph nodes

F. tularensis multiplies how?

1000 fold in macrophages

F. tularensis mortality rate

<3%

What can trasmit F. Tulameria?

• 90% (Rabbit fever)

• ticks

• deer flies

• What can F. tulameria cause (+mortality)?

• through what?

• acute resp infections (30%+ mortality)

• dust in urine/feces of infected animals

3 reasons F. tulameria a bioterrorism threat?

• Extremely low infectious dose;

• aerosol-dangerous;

• requires BSL-3/4.

F. tulameria treatment

Tetracycline (bc intracellular)

Legionella morphology 5 characteristics

• gram neg bacillus

• aerobic

• thin

• pleomorphic

• flagella

When did Legionella emerge?

1976

What 2 diseases does Legionella make

Legionnaires’ disease & Pontiac fever.

Legionella was identified as _ in what year

• nationally notifiable infec

• 2008

How many U.S. cases of per year?

8-18k

4 Environments where Legionella thrives?

• a

• warm hospital water lines

• water in AC cooling towers

• aquatic amoeba

• streams

Stain used to view Legionella?

silver stain

What media can Legionella grow on suitably

artificial media

• How was Legionellosis exception to Koch’s postulate?

• How did researchers resolve this?

• unable to isolate the microbe directly from victim →

• inoculated lung tissue into guinea pigs

How can legionella spread & how long incubated?

• thru aerosols

• inhalated thru mist droplets

• 2 weeks

Legionella symptoms initial vs advanced

• Flu-like (fever, chills, dry cough)

• pneumonia, diarrhea, nausea, GI, & neurological symptoms.

Why is Legionella considered for bioterror?

Legionella pneumophila strain 100% death rate animals

Campylobacter 4 Morphology characteristics

• gram neg

• microaerophilic vibrios

• 1 polar flagellum

Campylobacter is responsible for over _

2 million foodborne infections

2 diseases of Campylobacter what they cause

• C. jejuni: lead outbreak of food borne intestinal disease 

• C. fetus: spontaneous abortion in domestic animal