Leptospira

Question 1

What are the two main species of Leptospira?

Answer 1

L. interrogans (pathogenic) and L. biflexa (saprophytic)

Question 2

What is the basic taxonomic unit for classification?

Answer 2

Serovar

Question 3

Describe the characteristic shape of leptospires:

Answer 3

Helical with hooked ends

Question 4

How do leptospires move?

Answer 4

Via two periplasmic flagella (endoflagella)

Question 5

What encloses the helical body and flagella?

Answer 5

An outer sheath (external envelope)

Question 6

What three components are essential in culture media?

Answer 6

Rabbit serum or BSA, Long-chain fatty acids (Tween 80), Vitamins B₁ and B₁₂

Question 7

What are the optimal growth conditions?

Answer 7

30°C, pH 7.2, aerobic

Question 8

What energy sources do they use?

Answer 8

Long-chain fatty acids (cannot use carbohydrates)

Question 9

Where do pathogenic leptospires primarily reside?

Answer 9

Renal tubules of reservoir hosts

Question 10

How are they transmitted between hosts?

Answer 10

Through urine-contaminated water/soil

Question 11

What three factors favor environmental survival?

Answer 11

Moisture, slightly alkaline pH, moderate temperatures

Question 12

What are the two main bovine-adapted serovars?

Answer 12

hardjo and pomona

Question 13

What is “milk-drop syndrome”?

Answer 13

Agalactia with yellow, clotted milk (serovar hardjo)

Question 14

What renal pathology does serovar pomona cause?

Answer 14

Interstitial nephritis

Question 15

What are the three clinical forms in dogs?

Answer 15

Acute hemorrhagic, Icteric, and Uremic (Stuttgart disease) (sv. Canicola)

Question 16

What is Weil’s disease?

Answer 16

Severe leptospirosis caused by serovar icterohaemorrhagiae

Question 17

What are the three main diagnostic methods?

Answer 17

Dark-field microscopy

Culture (Fletcher/Ellinghausen media)

MAT (Microscopic Agglutination Test)

Question 18

What is the most sensitive detection method?

Answer 18

Hamster inoculation

Question 19

What two antibody classes are produced?

Answer 19

Early IgM (agglutinating)

Later IgG (protective)

Question 20

What is a key feature of canine vaccines?

Answer 20

Contain killed serovars canicola and icterohaemorrhagiae

Question 21

What causes hemoglobinuria in calves?

Answer 21

Hemolysins from certain serovars

Question 22

What ocular condition is associated with equine leptospirosis?

Answer 22

Periodic ophthalmia (iridocyclitis)

Question 23

What serovar affects sugarcane workers?

Answer 23

australis (“canecutter’s fever”)

Question 24

Leptospires can use carbohydrates as energy sources. (T/F)

Answer 24

False

Question 25

The outer sheath contains protective antigens. (T/F)

Answer 25

True

Question 26

Which Leptospira serovar causes "harvest fever" in rice-field workers?

Answer 26

Serovar bataviae

Question 27

Which serovar are commonly infect Farmers, agricultural workers, and flax workers?

Answer 27

serovar grippotyphosa