Histophilus & Glaesserella

Question 1

Characteristics of Histophilus and Glaesserella

Answer 1

-gram negative cocco-bacilli
-biocontainment level 2
-facultative anaerobes
-fastidious

Question 2

Host of Histophilus somni

Answer 2

-respiratory and reproductive tract

Question 3

Host of Glaesserella parasuis

Answer 3

-pigs
-early colonizer of respiratory tract
-mucous membranes
-lower genital tract

Question 4

Different factors involved in taxonomy

Answer 4

Nutritional requirements for Factor X OR Factor V

Question 5

Factor X

Answer 5

-Haemin
-heat stable, found in adequate amounts in blood agar

Question 6

Factor V

Answer 6

-NAD
-found inside RBCs

**is liberated from blood cells in chocolate agar
-not sheeps blood because in contains inactivating enzyme
-use rabbit, horse, or chocolate agar

Question 7

Virulence factors for Glaesserela parasuis

Answer 7

1.capsule-adhesion, invasion

2. fimbriae- linked with encapsulated strains
3. Lipooligosaccharides- toxic lipid A component capable of phase variation= antigenic variation and immune evasion
4. Induces cells to eat it as a strategy for getting into cells

Question 8

Name -Histophilus vs. haemophilus

Answer 8

Haemophilus= blood loving

Histophilus= tissue loving

Question 9

Histophilus polymicrobial infections

Answer 9

Often with Trueperella and pasteurella multocidus

Question 10

Histophilus somni in cattle clinical signs

Answer 10

-often includes more than one organ

1. respiratory infection= shipping fever
   -fever, tachypnea, cough, nasal discharge
   -can be fatal
   -pain with pleuritis
2. thrombotic meningoencephalitis
3. septicemia
4. myocarditis (sudden death)
5. arthritis
6. Abortion
7. Enzootic calf pneumonia

Question 11

Lesions of histophilus somni

Answer 11

Lesions related to VASCULAR THROMBOSIS
-Will see tissue infarction and necrosis with hemorrhage

-in brain, heart, spinal cord, kidney, intestines

**clinical signs linked to site of thrombosis

Question 12

Treatment and control of histophilus somni

Answer 12

-antimicrobials
-vaccination

Question 13

Histophilus somni in sheep

Answer 13

-broad spectrum of pathologies in sheep

-lameness, septicemia, epididymitis-orchitis, metritis, abortion, mastitis

Question 14

Glaesserella parasuis

Answer 14

Presentation depends on site of infection and health status of herd
-Naive herd= rapid, pyrexia, inappetence, anorexia, abortion, lameness, rarely acute septicemic disease (rapid death)

-Glasser’s disease classical lesion= Fibrinous polyserositis and Leptomeningitis (inflammation of subarachnoid space)

-may be linked to porcine respiratory disease complex

Question 15

Transmission of Glaesserella parasuis

Answer 15

-associated with mixing herds; doesnt survive in environment. Need contact

-commonly pigs 4-8wks
-short incubation period (1-5days)

Question 16

Treatment of Glaesserella parasuis

Answer 16

-high dose antimicrobials early in disease

-vaccinate gilts (protective maternal immunity)
-beware of new introductions
-not mixing litters
-adequate colostrum intake

Question 16

Haemophilus influenzae

Answer 16

-Found in oro/naso pharynx of up to 85% of people
-clinical signs depend on site of infection (fever, chills, cough, difficulty breathing)
-associated with many diseases= meningitis, otitis media, epiglottis, acute sinusitis, phrayngitis, bronchitis, pneumoniae
-can be fatal and linked to hearing loss

Question 17

Treatment of Haemophilus influenzae

Answer 17

-was the most common cause of bacterial meningitis in kids, can be fatal.

-vaccines

Question 18

Sample collection

Answer 18

-joint fluid, CSF, heart blood, tissues with lesions
-part of normal microbiome so beware of contamination
-delicate, get to lab ASAP
-do not freeze!

Question 19

Lab ID

Answer 19

-Culture, biochemical ID, morphology, MALDI

-PCR based assays

-Serological testing

-Histological visualization

Question 20

Zoonoses

Answer 20

Pathogenic species tend to be host specific so not recognized as zoonoses

Question 21

Treatment

Answer 21

-Antimicrobials early in infection; Macrolide type (Erythromycin)

-Vaccines- Haemophilus in people, Glaesserella in pigs)

-No Beta-lactams

-Intrinsic resistance to streptogramins (virginiamycin)