Tularemia

Question 1

Describe the characteristics of Francisella tularensis? What disease does it cause?

Answer 1

Francisella tularensis is:
1. anaerobic 2. gram-negative 3. non-motile and 4. non-sporing 5. coccobacillus.
It is the causative agent of TULAREMIA

Question 2

How is Tularemia frequently spread? How else can it spread?

Answer 2

1. Tularemia is frequently spread by direct contact with rabbits (hence it’s called rabbit fever).
   2&3. However, it can also be spread by other animals, typically rodents, and by arthropods.

Question 3

What are the 6 different forms that Tularemia occurs in?

Answer 3

1. typhoidal
2. pneumonic
3. oculoglandular
4. oropharyngeal
5. ulceroglandular
6. glandular

Question 4

Why is Dx of tularemia difficult?

Answer 4

B/c the disease mimics many other illnesses.

Question 5

Pathogenesis of tularemia varies greatly dependin on what?

Answer 5

depending on the mode of infection

Question 6

What is the incubation period of tularemia?

Answer 6

about 3-5 days, but it can take as long as two weeks for symptoms to appear

Question 7

What are the symptoms of tularemia?

Answer 7

They vary based on the mode of infection, but generally include:
1. fever 2. chills 3. joint and muscle pain 4. headache 5. weakness and 6. sometimes pneumonia

Question 8

What are the symptoms of people who develop pneumonic tularemia?

Answer 8

They experience:

1. chest pain 2. bloody sputum, and 3. difficulty breathing

Question 9

How is tularemia treated? Is it curable?

Answer 9

The disease is effectively cure by antibiotic treatment

Question 10

How is tularemia spread? (4)

Answer 10

1. thru bites of ticks (wood, dog, and lonestar types) and deer flies
2. thru contact w/ contaminated water, blood, or tissue while handling carcasses of infected animals (skinning or dressing animals)
3. thru eating insufficiently cooked meat of infected animals
4. thru inhalation of dust from contaminated soil, hay, or grain

Question 11

The virulence of the tularemia organism lends itself to potential use as what?

Answer 11

as a biological weapon (it’s a Category A biodefense agent)

Question 12

What are some characteristics of Francisella tularensis that help it survive the innate immune response and the killing mechanisms and phagosomes of alveolar macrophages? (3)

Answer 12

a. LPS has reduced immunostimulatory property
b. The bacterial CAPSULE plays a role in resistance to complement
c. A number of protein products have been found to be important for survival in macrophages

Question 13

What is the incubation period of tularemia? How long does it take people exposed to it to become sick?

Answer 13

Most people exposed to tularemia who become sick generally do so w/in 2 to 10 days, but incubation can take as little as a few hours or as long as 3 weeks

Question 14

What are the 6 types of tularemia?

Answer 14

There are six types of tularemia, each with its own set of symptoms:

1. Ulceroglandular
2. Glandular
3. Oculoglandular
4. Oropharyngeal
5. Pneumonic
6. Typhoidal

Question 15

What is by far the most common form/type of tularemia? What are its signs and symptoms?

Answer 15

Ulceroglandular Tularemia
Signs/Symptoms:
1. A skin ulcer that forms at the site of infection (usually an insect or animal bite)
2. Swollen and painful lymph glands
3. Fever
4. Chills
5. Headache
6. Exhaustion

Question 16

What are the signs/symptoms of people with glandular tularemia?

Answer 16

They are the same as those for ulceroglandular, except NO SKIN ULCERS

Question 17

What does oculoglandular tularemia affect? What can it cause?

Answer 17

It affects the eyes and may cause:

1. Eye pain
2. Eye redness
3. Eye swelling and discharge
4. An ulcer on the inside of the eyelid

Question 18

What is oropharyngeal tularemia caused by? What does it affect?

Answer 18

It is usually caused by eating poorly cooked wild animal meat or drinking contaminated water. This form affects the digestive tract.

Question 19

What are the signs/symptoms of oropharyngeal tularemia?

Answer 19

1. fever 2. sore throat 3. vomiting 4. diarrhea

Question 20

In what individuals is pneumonic tularemia more common?

Answer 20

It is more common in:

a. the elderly
b. people with typhoidal tularemia

Question 21

What are the signs/symptoms of pneumonic tularemia?

Answer 21

Signs and symptoms typical of pneumonia:

1. cough
2. chest pain
3. difficulty breathing
4. other forms of tularemia also can spread to the lungs

Question 22

What is the rare and serious form of tularemia?

Answer 22

Typhoidal tularemia

Question 23

What are the signs/symptoms of typhoidal tularemia?

Answer 23

1. high fever
2. extreme exhaustion
3. vomiting and diarrhea
4. enlarged spleen
5. enlarged liver
6. pneumonia

Question 24

What is an important fact about tularemia epidemiology/transmission? (KNOW THIS)

Answer 24

Tularemia doesn’t occur naturally in humans and isn’t known to pass from person to person.

Question 25

Where does tularemia occur? Why?

Answer 25

It occurs worldwide, especially in RURAL areas, b/c many mammals, birds, insects, and fish are infected with F. tularensis.

Question 26

How long can F. tularensis live? Where can it live?

Answer 26

F tularensis can live for weeks in soil, water, or dead animals

Question 27

What are the several routes/modes of transmission of tularemia?

Answer 27

1. Insect bites 2. Exposure to sick or dead animals 3. Airborne bacteria 4. Contaminated food or water

Question 28

Why is the route/mode of transmission of tularemia important?

Answer 28

How you get the disease (the mode of transmission) usually determines the TYPE and SEVERITY of symptoms

Question 29

Although a number of insects carry tularemia, what two are most likely to transmit the disease to humans?

Answer 29

Ticks and Deerflies

Question 30

Tick bites cause a large number of cases of what type of tularemia?

Answer 30

Ulceroglandular tularemia

Question 31

Ulceroglandular tularemia can also form through what two ways?

Answer 31

(both via exposure to sick or dead animals) 1. It can result from handling or being bitten by an infected animal, most often a rabbit or hare. 2. Bacteria can enter the skin thru small cuts and abrasions or bites, and an ulcer forms at the wound site

Question 32

What can cause oculoglandular tularemia?

Answer 32

Rubbing your eyes after touching an infected animal (exposure to sick or dead animals)

Question 33

How can F tularensis in the soil become airborne? What form of tularemia can inhaling F. tularensis lead to? What other workers are at risk of airborne infection?

Answer 33

Bacteria in the soil can become airborne during gardening, construction, or other activities that disturb the earth. Inhaling it can lead to pneumonic tularemia. Laboratory workers who work with tularemia are at risk of airborne infection.

Question 34

What is the most uncommon mode of tularemia transmission? What type of tularemia and its associated signs and symptoms does this mode lead to?

Answer 34

Eating undercooked meat of an infected animal or drinking contaminated water. The signs include vomiting, diarrhea and other digestive problems (oropharyngeal tularemia)

Question 35

Why is well-cooked meat (at least 160F or 71C) usually safe to eat?

Answer 35

Heat kills F. tularensis

Question 36

What are the diagnostic tests used to Dx tularemia?

Answer 36

1. Blood culture for F. tularensis 2. Blood test measuring the body's immune response to infection (Serology for tularemia) 3. CXR 4. PCR test of a sample from an ulcer 5. Look at chart in the handout

Question 37

Tularemia affects the results of what tests?

Answer 37

It affects the results of febrile agglutinins and some tests for infectious mono.

Question 38

What is the DDx for Tularemia?

Answer 38

1. Any infectious skin agent causing a skin lesion 2. Tickborne infections (RMSF, Babesiosis) 3. Bacterial Septicemias 4. Flu, flu-like viral infections 5. Acute causes of pneuomonia, especially common causes of atypical pneumonia 6. Plague 7. Q fever 8. Anthrax

Question 39

What is the goal of treatment of Tularemia?

Answer 39

to cure the infection with antibiotics

Question 40

What drugs are commonly used to treat tularemia infections?

Answer 40

Streptomycin and Tetracycline

Question 41

In the treatment of tularemia, what is an alternative therapy to streptomycin?

Answer 41

gentamicin

Question 42

While tetracycline and chloramphenicol can be used alone to treat tularemia, why are they not considered a first-line treatment?

Answer 42

they have a high relapse rate