Haemophilus and Histophilus

Question 1

What bacterium causes Glasser Disease in pigs?

Answer 1

Haemophilus parasuis

Question 2

What does H. parasuis look like?

Answer 2

Gram neg bacilli to coccobacilli

Question 3

T/F: Glasser Disease, caused by H. parasuis is strictly an exogenous infection.

Answer 3

FALSE: H. parasuis is a facultative pathogen and commensal of the mucosa in pigs

Question 4

T/F: H. parasuis infection can happen between 2 weeks - 4 months of age, but is most common around weaning?

Answer 4

TRUE

Question 5

Septicemia caused by Haemophilus parasuis can affecct the pig in what 2 ways?

Answer 5

Meningitis (CNS signs)

Polyserositis/Polyarthritis (peritonitis, pleuritis)

Question 6

How and when are antibiotics administered for an H. parasuis infection?

Answer 6

Administered IM at the outbreak of infection, and ALL piglets in the litter are treated.

Question 7

What is a special consideration when culturing Haemophilus parasuis?

Answer 7

NAD dependent

Question 8

T/F: The best way to guarantee prevention of H. parasuis and Glasser Disease in pigs is to vaccinate.

Answer 8

FALSE: the vaccine sorta sucks and isn’t always successful

Question 9

What species of Haemophilus is present in healthy cats, but can cause pneumonia if chronic, and conjunctivitis?

Answer 9

Haemophilus felis

Question 10

T/F: Haemophilus infections in both pigs and cats are fairly common.

Answer 10

FALSE: both are rare

Question 11

What Histophilus species is an obligate symbiont of ruminants and colonizes the mucosal surfaces of the urogenital tract?

Answer 11

Histophilus somnei

Question 12

What are the symptoms of Histophilus somnei infection in ruminants? (there are a lot)

Answer 12

Septicemia
CNS (Sleepers dz)
Arthritis
Retinitis
Myocarditis
Mastitis
Abortion

Question 13

What disease is caused by Histophilus somnei and is characterized by CNS symptoms and a blood clot in the brain?

Answer 13

Sleepers disease

Question 14

What are the 4 virulence factors of Histophilus somnei?

Answer 14

LOS - lipooligosaccharides

OMPs

Host cell interactions

Biofilms

Question 15

Which virulence factor of H. somnei aids with immune evasion and complement resistance?

Answer 15

Lipooligosaccharides (LOS)

Question 16

Which virulence factor of H. somnei binds transferrin and Ig?

Answer 16

OMPs

Question 17

How does H. somnei interact with host cells to increase virulence?

Answer 17

Activation of caspases/apoptosis

Activation of thrombocytes

BOTH CAUSE INTRAVASCULAR COAGULATION

Question 18

T/F: Histophilus somnei is easy to diagnose with culture

Answer 18

FALSE: frequently overgrown and requires 5-10% CO2

Question 19

Antibiotics can be used for H. somnei infections, but won’t work against which clinical signs?

Answer 19

Septicemia
TEME
Myocarditis
Polyarthritis
Mastitis

Question 20

Can we vaccinate ruminants against Histophilus somnei?

Answer 20

YEP!