Symptoms
The first symptoms of rabies may be very similar to the flu and may last for
days. Signs and symptoms may include:
Fever
Headache
Nausea
Vomiting
Agitation
Anxiety
Confusion
Hyperactivity
Difficulty swallowing
Excessive salivation
Fear of water (hydrophobia) because of the difficulty in swallowing
Hallucinations
Insomni
Partial paralysis
Diagnosis in humans
Several tests are necessary to diagnose rabies ante-mortem (before death) in
humans; no single test is sufficient. Tests are performed on samples of saliva,
serum, spinal fluid, and skin biopsies of hair follicles at the nape of the
neck. Saliva can be tested by virus isolation or reverse transcription followed
by polymerase chain reaction (RT-PCR). Serum and spinal fluid are tested for
antibodies to rabies virus. Skin biopsy specimens are examined for rabies
antigen in the cutaneous nerves at the base of hair follicles.