Rabies Flashcards
Rabies - organism
Rabies lyssavirus
Rabies - transmission
Saliva from an infected animal (99% dogs)
Rabies - approach to treatment (acute bite management + in hospital)
First aid: wash wound for 15 minutes, use soap, avoid suturing where possible.
Remember tetanus vaccination and antibiotics
If immunocompromised and category 2 or 3 - give immunoglobulin and vaccination irrespective of vaccine status
If immunocompetent and vaccinated
Only give vaccine
If immunocompetent and not vaccinated
Category 1/2 - vaccine
Category 3 - vaccine & Immunoglublin
Rabies risk of exposure categories
Category 1 - licks or touching, no bite
Category 2 - minor scratches or nibbling
Category 3 - Direct contact with bats, contamination of mucous membranes, transdermal bites or scratches
Rabies clinical presentation
Incubation period 1-3 months
Prodromal: 1-2 days of non-specific symptoms like itching and pain at wound site, headache, fever, myalgia
Acute neurological phase: Encephalomyelitis
- Furious: hyperactivity, hallucinations, hydrophobia
- Paralytic: gradual paralysis without hyperactivity
Rabies - indications for intensive care
American bat virus exposure
ITU available
Early appearance of antibodies
Rabies - diagnostics
- Skin biopsy - immunofluorescense assay, PCR
- Saliva, tears, CSF - Tissue culture or PCR
- Serology - Serum, CSF
Brain needle necrospy post-mortem
Japanese encephalitis - what kind of virus + epidemiology
Zoonotic flavivirus in Asia and the Pacific
Japanese encephalitis - life cycle
Mammilian reservoir - pigs are the amplifying hosts
Humans are accidental dead-end hosts
Bitten by culex mosquitoes
Japanese encephalitis - diagnostics
IgM on seum/CSF
Can use PCR (limited as viraemia is brief)
Japanese encephalitis - clinical presentation
Incubation 5-15 days
Asymptomatic or mild flu-like symptoms
More severe when it invades the CNS
- Prodromal: fever, headache, vomiting, general malaise
- acute encephalitic phase: high fever, neck stiffness, photophobia
- seizures in children
- focal neurological deficites or movement disorders including parkinsonian features** - thalamitis with pyramidal features like cogwheeling etc
Japanese encephalitis - management
Supportive
No evidence for antivirals
Differentials for CNS infections
Bacterial:
SMILE
Strep pneumo
neisseria Meningitidis
haemophilus Influenza
Listeria monocytogenes
E coli
(also TB, burkholderia pseudomallei - meliodosis, orientia tsutsugamushi)
Spirochetes: Treponema pallidum, Borrelia spp.
Fungi:
Cryptococcus
Viral:
Herpes zoster
Enterovirus
HIV
Arboviruses - JE, dengue, chikungunya
Parasites:
Toxoplasma gondii
Taenia solium (neurocysticercosis)
Trypanosoma brucei (sleeping sickness)
Malaria
