Bacteria Flashcards
What kingdom are bacteria in?
Kingdom Eubacteria
What type of cells are bacteria?
Living cells.
How do bacteria live?
They are usually free living, but may be obligate intracellular parasites too.
What is the anatomy of bacteria?
Prokaryote or Eucaryote
They are prokaryotic with no nucleus, no membrane bound organelles.
What is the anatomy of bacteria?
Nucleus
They do not have a membrane bound nucleus. The DNA is free in the cytoplasm of the cell.
What is the anatomy of bacteria?
Plasma Membrane
They have a plasma membrane surrounded by a cell wall.
What is the anatomy of bacteria?
Cell Wall**
- Rigid, gives the bacterium its shape.
2. Thick and tough. Very important protective layer.
What is the anatomy of bacteria?
Cell Wal/Gram Stain**
The structure of the cell wall differs in Gram Pos. and Gram Neg. bacteria.
What is the anatomy of bacteria?
Size
- Considerable variation.
- About 1-10 micrometers in length
How many micrometers are in one meter?
1,000,000
Classification of bacteria is based on what 2 things?
- Gram reaction.
2. Shape
Is Gram reaction important in diagnosis and treatment?
Yes, it is very important. Many antibiotics will work on one Gram group and not the other.
Gram Positive Bacteria
- Stain purple.
- Have a thicker cell wall.
Gram Negative Bacteria
- Stain light pink / orangish.
- Thinner cell wall.
What are the 3 major shapes of bacteria?
- Coccus (Cocci)
- Bacillus (Bacilli)
- Spirillum (Spirilli)
What shape is Coccus / Cocci bacteria?
Round
What shape is Bacillus / Bacilli bacteria?
Rod
-bacteria is sometimes called rods instead of bacilli.
What shape is Spirillum / Spirilli bacteria?
Spiral
- look like tiny corkscrews
- much less common than cocci and bacilli.
How are bacteria classified?
All bacteria are classified according to Gram reaction and shape.
ex: Gram Neg. bacillus, Gram Pos. bacillus, Gram Pos. coccus
What is the life cycle of bacteria?
It is very simple.
- no immature or juvenile stages.
- divide by binary fission.
What is binary fission?
When one adult cell divides into two new adults.
How is bacteria diagnosed (5 steps)?
- Collection of specimen from patient.
- May involve evaluation under a microscope of live bacteria.
- Usually requires culture of bacteria on media.
- Gram Staining and other lab tests.
- May use antibody tests.
What is sometimes done for a definitive diagnosis with bacteria?
Culture may be sent to another lab.
In what way are bacterial infections treated?
Antibiotics - antimicrobial agents.
Can you use one antibiotic for everything?
No. Each one is effective against specific groups of microorganisms.
*called the SPECTRUM of the antibiotic
What about bacterial resistance?
Many have become resistant to antibiotics. Should test cultures for antibiotic sensitivity.
What does Staphylococcus spp look like?
- Gram Pos. Coccus
- Occurs in clumps, look like a clump of grapes.
Staphylococcus spp resistance?
Extremely resistant to destruction in the environment.
Where are Staphylococcus spp found?
Ubiquitous, they are found everywhere.
Staphylococcus spp and skin?
They are normally found on the skin.
*can infect body through skin lesions or mucous membranes.
What is the most common Staphylococcus spp?
Staphylococcus aureus
What is Staph spp commonly isolated from?
Often from pyogenic lesions.
- infected wounds
- dermatitis (red, sore, scaly skin)
- otitis
- conjunctivitis
- cystitis, maybe cellulitis
- many others
What is a common disease caused by Staph spp?
Mastitis: causes decrease in milk production and visible change in quality of milk.
What can happen if Staph spp. Infections are not treated?
It can become systemic and enter the blood.
What else can Staph spp. cause?
- common cause of skin and subcutaneous infections.
- common cause of urinary infections.
What does Streptococcus spp. look like?
Gram Positive Coccus occurring in chains or pairs.
-looks like beads on a string.
Where is Streptococcus spp. found?
In the mucous membranes. -tonsils -skin -intestinal tract -bovine udder -others Some are fecal.
What kind of pathogens are Streptococcus spp?
They are mainly opportunistic pathogens.
Does Streptococcus spp last long in the environment?
All but the fecal strep do not survive long in the environment.
How is Streptococcus spp transmitted?
- Through direct contact or aerosol.
- Often through the milkers hands and milking machines.
What can Streptococcus cause in all mammals?
Can cause pyogenic infections and mastitis.
What does Streptococcus spp cause in dairy cows and goats?
- One of the most common causes of Mastitis.
- Can be acute or chronic.
- Can cause great economic losses in dairy industry.
What is Streptococcus spp a common cause of in horses?
Strangles
What is another name for Strangles?
Equine Distemper.
What causes Strangles?
Staphylococcus equi
What symptoms does Strangles have?
Causes pus-like discharge from nose and swollen throat and lower jaw.
- hard to swallow “strangles”.
- lymph nodes in neck fill with pus and often burst.
- fever, depression, etc.
How is Strangles diagnosed?
Culture S. equi from pus from nostrils.
Is Strangles fatal?
Not usually, horse usually recovers.
Is Strangles contagious, how is it transmitted?
Very contagious within a herd.
Transmitted by:
-passed easily by food, water, tack.
-direct or indirect contact.
Strangles and vaccination.
There is a nasal aerosol vaccine that is very good.
Is Strangles zoonotic?
No, it is not.
What does Streptococcus cause in swine?
It can cause meningitis or septicemia.
What is the Streptococcus that causes illness in swine?
Streptococcus suis
What does meningitis do in swine?
It infects the CNS.
- lameness, convulsions, paralysis, death.
- death may be sudden.
What does septicemia do in swine?
- Fading piglet syndrome.
- mostly in wrangling pigs.
- Pneumonia, often leading to sudden death.
What bacteria causes fading piglet syndrome?
Streptococcus suis
Is Streptococcus suis zoonotic?
Yes.
- It is passed to humans through wounds on skin or on mucous membranes.
- Can cause bacterial meningitis or TSS in humans
Do all pigs with Streptococcus suis show symptoms?
No. They may be asymptomatic carriers.
What causes Lyme Disease?
Borrelia burgdorferi
-Causes Lyme Disease in dogs, humans, and cats.
What does Borellia burgdorferi look like?
Gram negative spirillum
Does Borellia burgdorferi grow slowly or fast?
It is a very slow growing bacteria.
How does Lyme Disease grow in the environment?
Not very well.
- it cannot be grown in a lab.
- the exception is that it grows really well in some animal hosts.
What is the reservoir host for Lyme Disease?
Voles and mice (mainly mice)
What are the transport hosts for Lyme Disease?
Deer ticks or black legged ticks.
-in the Northeast mostly Ixodes scapularis
How is an animal infected with Lyme Disease?
- The tick picks up the organism from a mouse or vole.
- Transports it to the animal or human by biting.
Where are Lyme Disease bearing ticks found?
Mostly in grasslands and woodlands. They like to feed on deer, sheep, horses, and rodents.
Is Lyme Disease the same in dogs and cats?
It is similar, but more severe in dogs.
What are the symptoms of Lyme Disease?
- Sudden lameness of one or more joints.
- Swelling of joints and lymph nodes.
- Also may be fever, anorexia, lethargy.
How long do the symptoms of Lyme Disease last?
Only three to four days. However, they can recur at intervals of every several weeks or months.
What happens in more serious cases of Lyme Disease?
In some cases it may cause sever heart, kidney, or neurological problems. It can cause arthritis over time.
Are all animals with Lyme Disease symptomatic?
No. They may be in fetched, but never show signs of illness.
When does lameness set in with Lyme Disease?
2 to 5 months after infection.
How is Lyme Disease treated?
With antibiotics.
How do animals respond to treatment for Lyme Disease?
Most animals respond within three to four days.
Can an animal get Lyme Disease more than once?
Yes, they may be reinfected.
How is Lyme Disease prevented?
There is a vaccine, but it is not always recommended. Tick prevention and removal is best.
Why is the Lyme Disease vaccine not recommended?
It has many side effects.
What is the cause of Ehrlichiosis?
Ehrlichia canis and Erchlichia ewingii
In what animal is Ehrlichiosis common?
Dogs
What kind of bacteria is Ehrlichia canis and Erchlichia ewingii?
It is a Rickettsia
What does Ehrlichia canis and Erchlichia ewingii look like?
A small Gram Negative obligate intracellular cocci.
What does Ehrlichiosis infect?
It infects and lives inside white blood cells.
What type of disease is Ehrlichiosis?
A leukotrophic disease.
What are the 2 forms of Ehrlichiosis?
CME - Canine Monocytic Ehrlichiosis
CGE - Canine Granulocytic Ehrlichiosis
What are granulocytes and monocytes?
They are types of white blood cells.
What is the cause of CME?
Ehrlichia canis
What does CME infect?
It infects monocytes.
What are the major symptoms of CME?
Lack of platelets and bleeding.
What is the cause of CGE?
Erchlichia ewingii
What does CGE infect?
Mainly neturophils (WBC)?
What are the main symptoms of CGE?
Lameness, joint swelling, polyarthritis (arthritis in multiple joint.s
What are the general symptoms of Ehrlichiosis?
It is multi-systemic and has rather nonspecific symptoms.
What are the 3 phases of Ehrlichiosis?
- Acute
- Subclinical
- Chronic
What symptoms occur in the acute phase of Ehrlichiosis?
Mild, lethargy, loss of appetite, enlarged lymph nodes, low platelet count, joint pain.
Do dogs recover from the acute phase of Ehrlichiosis?
Yes, they do.
How long does the acute phase of Ehrlichiosis last?
2 to 4 weeks.
What happens during the acute phase of Ehrlichiosis?
During this phase, it is infecting the wbc’s and the spleen.
Where do WBC’s live?
In the lymphatic tissue.
What symptoms occur during the subclinical phase of Ehrlichiosis?
Dogs appear to be normal.
How long does the subclinical phase of Ehrlichiosis last?
It can last up to several years.
Where is the organism hiding during the subclinical phase of Ehrlichiosis?
It is hiding in the spleen.
What happens during the chronic phase of Ehrlichiosis?
The dog will get sick again.
What symptoms will the dog show during the chronic phase of Ehrlichiosis?
- May have abnormal bleeding (low platelet count).
- Kidney damage, loss of blood cells (leukopenia)
- May have neurological symptoms and arthritis.
What is a dog commonly diagnosed with during the chronic phase of Ehrlichiosis?
Leukemia
How is Ehrlichiosis transmitted?
By ticks (mainly the brown dog tick).
How is Ehrlichiosis diagnosed?
- By symptoms: fever, enlarged lymph nodes, bleeding, low platelet counts.
- With a blood (snap) test.
How is Ehrlichiosis treated?
With antibiotics, mainly Doxycycline and Tetracycline.
How is Ehrlichiosis prevented?
Tick control.
What does Clostridium spp. look like?
Gram positive bacillus, club shaped with endospore.
Is Clostridium spp. always pathogenic.
No, it can be a beneficial bacteria.
What is Clostridium spp.?
A large, anaerobic, spore forming bacteria.
What can Clostridium spp. produce?
Toxins that produce extensive tissue damage.
What can accompany a Clostridium spp. infection?
An accumulation of gas.
Where is Clostridium spp. normally found?
Soil, sewage, feces, water, feed, and GI tract of herbivores.
How long can Clostridium spp. survive?
- In boiling water, for half an hour.
- In the soil, for years.
What is one way to treat Clostridium spp. infections?
A hyperbaric chamber.
Are antibiotics effective against Clostridium spp.?
No. They are very resistant.
What 3 diseases does Clostridium spp. cause?
- Enterotoxemia
- Tetanus
- Botulism
What is the cause of Enterotoxemia?
Clostridium perfringens
What are the symptoms of Enterotoxemia?
- Dysentery, diarrhea, toxemia, vomitting.
- Hemorrhagic gastroenteritis, mostly in dogs.
Can Enterotoxemia be fatal?
In ruminants and swine.
-high mortality rate in lambs, calves, pigs, foals.
How does Clostridium perfringens enter an animal?
It is ingested by the host.
What is the cause of Tetanus?
Clostridium tetani
What does Clostridium tetani produce?
Tetanus toxin.
Who does Tetanus infect?
All species of domestic animals.
-especially horses
How does Tetanus enter the animal?
Via a puncture wound.
What is the first sign of Tetanus?
Animal may seem nervous, have a stiffness in gait.
What are other symptoms of Tetanus?
Muscular Spasms
- especially in head and neck.
- lockjaw (masseter muscle)
How does an animal with Tetanus die?
By dehydration.
What is the cause of Botulism?
Clostridium botulinum
What does Clostridium botulinum produce?
A very powerful neurotoxin.
How does Botulism enter an animal?
It can be ingested, or it can enter the host through a wound.
What are the symptoms of Botulism?
Ataxia, recumbency, paralysis starting in the hind quarters.
Where is one place that Clostridium botulinum is easily found?
At the bottom of a pile of hay, especially wet hay.
What does Escherichia coli look like?
Small Gram Negative rods (or coccobacilli)
What is E. coli normally a part of?
The intestinal flora, but it can cause disease under the right circumstances.
What is the most common way that E. coli is transmitted?
The fecal-oral route.
What is E. coli a cause of in many animals?
Diarrhea, vomitting, gastroenteritis
Is E. coli serious?
It can cause death due to dehydration.
Who is E. coli especially dangerous to?
Suckling and weanling pigs and neonatal calves.
What types of infections can E. coli cause?
Urinary tract infections and upper respiratory infections.
What can it cause in dairy cows?
Mastitis
What are Salmonella, Klebsiella, and Proteus similar to?
E. coli
What are Salmonella, Klebsiella, and Proteus called?
Enteric organisms
What does Salmonella do in a dog?
Common cause of diarrhea.
What does Pasteurella multocida look like?
Small Gram Negative bacilli (or coccobacilli)
What does Pasteurella multocida cause?
A wise variety of disease in many different animals.
Where is Pasteurella multocida most commonly found?
In a bite wound.
Is Pasteurella multocida serious?
It is a serious infection in animals and humans.
Where does Pasteurella multocida infect dogs and cats?
In wounds
Where Pasteurella multocida normally found in dogs and cats?
The mouth.
What kind of pathogen is Pasteurella multocida?
Opportunistic
What type of infection does Pasteurella multocida cause in most animals?
Upper respiratory tract.
What does Pasteurella multocida cause in rabbits?
Snuffles
Is snuffles fatal?
It can be.
What can snuffles infect if left untreated?
- The heart and uterus.
- Can become septic.
What types of infections does Snuffles cause?
Pneumonia and upper respiratory infections.
What are the symptoms of Snuffles.
Sneezing, coughing, runny eyes and nose.
What does Pasteurella multocida cause in swine?
Swine plague
What are the symptoms of Swine Plague?
- Pneumonia-like symptoms.
- High fever, cough, anorexia.
Is Swine Plague a primary or secondary infection?
It is almost always a secondary infection.
What can Swine Plague progress to?
Meningitis.
How are Pasteurella multocida infections treated?
Penicillin and other antibiotics.
Is Pasteurella multocida zoonotic?
Yes, through bites and scratches from animals.
Who does Pasteurella multocida commonly infect?
Veterinary workers
What type of infection does Pasteurella multocida normally cause in humans?
Usually a skin infection.
What can Pasteurella multocida cause in humans?
Pneumonia.
Is Pasteurella multocida fatal to humans.
Not usually, though it can lead to meningitis.
What does Bordatella bronchiseptica look like?
Small Gram Negative bacilli (and coccobacilli)
Where is Bordatella bronchiseptica found?
It is normally found in the upper respiratory tract of dogs and swine.
What does Bordatella bronchiseptica do to dogs/rabbits?
Often causes secondary infection in dogs with viral infections.
-rabbits with snuffles.
How is Bordatella bronchiseptica spread?
Droplet inhalation.
What are the symptoms of Bordatella bronchiseptica?
-Honking, unproductive cough.
What disease does Bordatella bronchiseptica cause in dogs?
A cause of kennel cough or bronchopneumonia in dogs.
Is Bordatella bronchiseptica contagious?
It is highly contagious.
What other animals can Bordatella bronchiseptica infect?
Pigs and cats in addition to dogs and rabbits.
What were Anaplasma phagocytophilium or Anaplasma platys originally classified as?
Until 2001 they were classified as Ehrlichia genus.
What do Ehrlichia and Anoplasma have in common?
They are both rickettsial infections of the blood.
Do all animals infected with Anaplasma phagocytophilium or Anaplasma platysshow signs of infection?
Most do not show signs of disease. They are subclinical carriers.
What are the symptoms of Anaplasma phagocytophilium?
- Mild, flu-like symptoms.
- Fever, lethargy, anorexia.
- General muscle pain (reluctance to move).
What does Anaplasma phagocytophilium do in a healthy animal?
It it self-limiting in a healthy animal.
How long does infection last in healthy dogs?
One to a few days.
What are the chronic and noticeable symptoms of Anaplasma phagocytophilium?
- Closely mimic those in Lyme Disease.
- Joint pain and lameness (polyarthritis)
Which set of symptoms are the more common?
The chronic symptoms are the most common.
What happens in rare cases of Anaplasma phagocytophilium?
May cause other disorders such as diarrhea, vomiting, and sometimes respiratory.
Can dogs become carriers of Anaplasma phagocytophilium?
Some dogs my become essentially asymptomatic carriers.
How is Anaplasma phagocytophilium transmitted?
Eastern US: Ixodes scapularis
Western US: Ixodes pacificus
*prefers reptiles to mammals.
What must happen for Anaplasma phagocytophilium to be transmitted to dogs?
It must bite dog for at least 24 hours to transmit disease.
How many dogs in the northeast US test positive for Anaplasma phagocytophilium?
80% - it is endemic
How many dogs in the western US test positive for Anaplasma phagocytophilium?
20%
How is Anaplasma phagocytophilium diagnosed?
Snap test.
What does the snap test for with Anaplasma phagocytophilium?
It tests for exposure not for clinical disease. Many subclinical or not ill patients will test positive on this.
What can the snap test for Anaplasma phagocytophilium distinguish between?
Ehrlichiosis and Lyme Disease
What can Anaplasma phagocytophilium be easily confused with?
Lyme Disease
-lameness, polyarthritis
What are clinical symptoms of Anaplasma phagocytophilium?
-Possible fever, weight loss, anorexia, vomiting.
What do patients test positive for in addition to Anaplasma phagocytophilium?
In our area, Anaplasmosis and Lyme Disease are often found in the same patient.
What are the hematologic symptoms of Anaplasma phagocytophilium?
- Seeing morula in neutrophils of infected animals.
- Thrombocytopenia mild to severe.
Is it hard to see morula in netorphils of animals infected with Anaplasma phagocytophilium?
Yes. Doing a buffy coat smear helps id this.
What is thrombocytopenia?
Low platelet count.
How is Anaplasma phagocytophilium treated?
Doxycycline and related antibiotics.
How is Anaplasma phagocytophilium prevented?
Tick control. There is no vaccine.
Is Anaplasma phagocytophilium zoonotic?
Yes, but not directly from a dog. From a tick bite.
What is the major reservoir for Anaplasma phagocytophilium?
White tailed deer and several small rodents including mice and voles.
What does Anaplasmosa platy infect?
Mainly platelets.
What does Anaplasmosa platy cause?
Infectious cyclic thrombocytopenia disease (infects platelets).
What type of disease is Anaplasmosa platy?
A tick borne rickettsial disease.
What tick is responsible for Anaplasmosa platy?
- Rhipicephalus (Wood Tick)
- Dermacentor (Brown Dog Tick)
What animal is mainly affected by Anaplasmosa platy?
Dogs
Do all dogs show symptoms of Anaplasmosa platy?
Most infected dogs will have no or mild clinical disease.
What does Anaplasmosa platy do in severe cases?
- Thrombopenia with inclusion bodies visible in platelets.
- This is cyclic in two or three week intervals.
What are the symptoms of the acute form of Anaplasmosa platy?
Pale mucous membranes, lethargy, and fever.
How is Anaplasmosa platy diagnosed?
- With a whole blood smear.
- Morula in circulating platelets.
- Snap test.
How is Anaplasmosa platy treated?
With antibiotics.
