Rabies

Question 1

• Organism Type: neurotropic viruses in the family Rhabdoviridae
• Scientific name: Lyssavirus
• Subtypes: All 17 viruses in the lyssavirus genus cause rabies in mammals.
• Common Name(s): ‘hydrophobia,’ ‘Lyssa’
• Prevalence: Extremely rare in the U.S.; ~59,000 deaths globally each year. Endemic to Africa, Asia, parts of Central and South America
• Predisposing Factors: Veterinarians, wildlife researchers, exposure to bat colonies, feral/unvaccinated dogs & cats in developing countries.

Answer 1

Rabies

Question 2

• Transmitted Via: Spreads through infected saliva inoculated through a break in the skin. Dogs account for 99% of all rabies transmissions to humans.
• Vector: Any mammal infected with rabies becomes a vector by default.
• Incubation Period: 1-3 months; length of incubation period dependent on site of inoculation
• Vaccine Preventable: Yes
• Reportable: Yes
• Lethal: Yes; once the rabies virus reaches the CNS it has a 99.9999% fatality rate

Answer 2

Rabies

Question 3

fatal, acute, progressive encephalomyelitis caused by neurotropic viruses in the family Rhabdoviridae, genusLyssavirus

Answer 3

Rabies

Question 4

How is rabies transmitted

Answer 4

Transmission occurs Secondary to inoculation of saliva from the bite of a rabid animal.

Question 5

Does human-to-human transmission of rabies occur?

Answer 5

Rarely except for rare cases of infection secondary to organ transplantation

Question 6

Major rabies reservoirs

Answer 6

major rabies reservoirs are terrestrial carnivores and bats.

Question 7

Clinical rabies typically manifests as 1 of 2 major forms:

Answer 7

• Encephalitic “furious”
  Fever, hydrophobia, pharyngeal spasms, hyperactivity subsiding to paralysis, coma & death
  ANS instability: hypersalivation, lacrimation, diaphoretic, “goose flesh”, dilated pupils.
• Paralytic “dumb”
  Ascending paralysis that is similar to Guillain-Barre
  Lost of DTR & plantar reflex
  Cranial Nerve Palsy possible

Question 8

What is the most characteristic feature of rabies

Answer 8

• Hydrophobia
• Patient becomes afraid of water due to involuntary pharyngeal muscle spasms when they attempt to drink

Question 9

What is Aerophobia

Answer 9

• Pathognomonic pharyngeal muscle spasms triggered by feeling draft of air
• Leads to aspiration, coughing, choking, and if severe asphyxiation and respiratory arrest

Question 10

• Reported exposure (bite/scratch) from a feral or any animal in any country or developing nation in the past 90 days.
• The exposure history can be difficult to elicit given that several weeks to months may have elapsed since the exposure occurred.
• Fever & chills with paresthesia(s) surrounding animal bite site

Answer 10

Rabies