brain, spinal cord, and nerve disorders
Rabies
Diagnosis of Rabies
Examination and testing of samples of skin, saliva, and cerebrospinal fluid (obtained by spinal tap) Doctors suspect rabies when people have a headache, confusion, and other symptoms of the disease, especially if people have been bitten by an animal or exposed to bats (for example, if they were exploring a cave). However, many people with rabies are unaware of having been bitten by an animal or exposed to bats. A sample of skin is taken (usually from the neck) and examined under a microscope (skin biopsy) to determine whether the virus is present. Samples of saliva are also examined to check for the virus. A Spinal Tap (lumbar puncture) is done to obtain a sample of cerebrospinal fluid (the fluid that flows through the tissues that cover the brain and spinal cord). This sample is also examined. The polymerase chain reaction (PCR) technique, which produces many copies of a gene, is often used to identify the virus's unique DNA sequence in a sample of skin, cerebrospinal fluid, or saliva. Several samples of the fluids, taken at different times, are tested to increase the chances of detecting the virus. 