25 – Histophilus and Glaesserella Flashcards
Microbiological Characteristics
- Gram negative COCCO-BACILLI
- Biocontainment level 2
- Facultative anaerobes
- Fastidious
- *Glaesserella is a new genus (2020)
What is the natural host or habitat of Histophilus somni?
- Respiratory and reproductive tract
What is the natural host or habitat of Glaesserella parasuis?
- Particularly pigs
- Early colonizer of respiratory tract
- Mucous membranes
- Lower genital tract
Taxonomy: requirement factors
- Factor X
o Haemin - Factor V
o NAD - *Used to figure out the species
Virulence factors of Glaesserela parasuis
- Capsule
- Fimbriae
- Lipooligosaccharide
- *induces cells to eat it (autophagy) to get in
- Strain variation in virulence is recognized
What does Histophilus somni in cattle cause?
- *more than one organ system
- Respiratory infection (shipping fever)
o Fever, tachypnea, cough, nasal discharge
o Can be FATAL
o Pain associated with pleuritis
o Congested lungs with multifocal areas of necrosis
What are other organ systems that can be involved with Histophilus somni in cattle?
- Thrombotic meningoencephalitis
- Septicemia
- Myocarditis: sudden death
- Arthritis
- Abortion
- Enzootic calf pneumonia
The lesions of Histophilus somni are related to vascular thrombosis?
- Tissue infarction and necrosis with haemorrhages
o Brain, heart, SC, kidney, intestine
What are the clinical signs related to site of thrombosis in cattle with Histophilus somni?
- Thrombotic meningoencephalitis in older calves and yearlings
o Depression, fever, blindness, coma and sudden death
How do you treat Histophilus somni in cattle?
- Antimicrobials
How do you control Histophilus somni in cattle?
- Vaccination
What is the disease and clinical signs of Histophilus somni in sheep?
- Similarly broad spectrum of pathologies
- Lameness
- Speticemia
- Epididymitis-orchitis
- Metritis
- Abortion
- Mastitis
What is the presentation of Glaesserella parasuis in pigs?
- Depends on site of infection
- *may play a role in porcine respiratory disease complex
- *usually in pigs 4-8 weeks old
- Short incubation: 1-5 days
What are the clinical signs seen in NAÏVE HERDS?
- RAPID ONSET OF DISEASE
- Pyrexia, inappetence, anorexia
- Aboriton in gilts
- Lameness chronically
- Rarely acute septicemic disease: rapid death
What are the symptoms of Glasser’s disease in pigs with Glaesserella parasuis?
- Fibrinous polyserositis=classical lesion
- Leptomeningitis: inflammation of subarachnoid space
How is Glaesserella parasuis in pigs spread?
- CONTACT!
o Very important with mixing herds
How is Glaesserella parasuis in pigs treated?
- HIGH DOSES of antimicrobials EARLY in course of disease
How is Glaesserella parasuis in pigs controlled?
- Vaccination in gilts: ensuring protective MATERNAL immunity
- Beware of new introductions
- Not mixing litters
- Adequate colostrum intake
Haemophilus influenzae in humans
- Found in oro/naso pharynx of up to 85% of people
- Clinical signs depend on site of infection
o Fever, chills, cough, difficulty breathing - *before vaccines it was the most common cause of bacterial meningitis in kids 1 month to 2 years old
What are some diseases that Haemophilus influenzae in people is associated with?
- Meningitis
- Otitis media
- Epiglottitis
- Acute sinusitis
- Pharyngitis
- Bronchitis
- Pneumoniae
What is the cause fatality of Haemophilus influenzae in children?
- 3-6%
- *hearing loss following infections in ~20% of patients
- *incidence in children has decreased 99% since late 80s
What are the common themes of Haemophilus influenzae in people and what we see in animal species?
- Colonizes upper respiratory tract
- Multisystemic disease
- Occurs when susceptible populations mix
Sample collections
- From affected tissues
o Joint fluid, CSF, heart blood, tissues with lesions
Sample handling
- Beware of contamination!
- Organisms are delicate
- Don’t survive well outside of hosts
- Get them to the lab quick!
- Do NOT freeze
Lab ID
- Culture: chocolate, biochemical ID, morphology, MALDI
- PCR based assays
- Serological testing
- Histological visualization
Zoonotic/interspecies transmission
- Pathogenic species tend to be HOST SPECIFIC
o Animal species are LIMITED to hosts - NOT RECOGNIZED AS ZOONOSES
Treatment options
- Antimicrobials EARLY in infection
- Macrolide type drugs (ex. Erythromycin)
- *vaccines important! (Glaesserella parasuis)
- *intrinsic resistance of streptogramins
Human Haemophilius spp and treatment options
- Do NOT typically produce beta-lactamases
o Included a beta-lactamase inhibitor will NOT help - For us: If resistant to one of your penicillin than reach for another class of drugs!
o Amoxicillin/clavulanate will NOT be effective against ampicillin resistant isolates
o Clavulanate acid: usually prevents the beta-lactamases from working
