Final answer:
Rabies vaccines can be given after a person has been exposed to the virus, leveraging the delay in disease progression to generate an immune response capable of neutralizing the virus and preventing fatal outcomes.
Step-by-step explanation:
Rabies is one of the few diseases in which the vaccine can be given successfully after exposure to the virus. The slow progress of the disease allows for a window of opportunity to administer a post-exposure vaccine, developing active immunity that can prevent the virus from reaching the central nervous system and causing fatal neurological damage. To aid in this process, a patient may receive human rabies immune globulin along with the vaccine, providing passive immunity by neutralizing any free viral particles, thus preventing the establishment of an active infection. This treatment methodology applies even in the face of potential exposure to other dangerous viruses, such as Ebola.
The principle of using vaccines in an active infection relies on their ability to elicit a rapid immune response, giving the body a head start in the fight against the invading pathogen. In the United States, the low incidence of rabies can be attributed to the widespread vaccination of domestic animals like dogs and cats, as well as the use of oral vaccines to control the disease in wildlife, ensuring public health safety.