A 9-year-old girl is playing in a wooded area of her backyard. She notices a furry animal in the brush. As it does not seem to fear her, she approaches to pet it. As soon as she touches the creature, it bites her and runs away. Her parents bring her to the emergency room for evaluation. The emergency room physician is extremely concerned that the patient may have been exposed to a deadly virus and orders immediate injections of immunoglobulin. From the brain, this pathogen establishes itself for transmission to another host by spreading to which of the following?

a. Intestines

b. Nasopharynx

c. Lungs

d. Bladder

e. Salivary glands