Читать книгу Basic Virology - Martinez J. Hewlett - Страница 71
Rabies
ОглавлениеSome viral diseases have very high mortality rates despite being well established in a population. With rabies, for example, injection of virus via the saliva of an animal bearing active disease leads to unapparent early infection, followed by a long incubation period of two to eight weeks or more depending on the species and individual. During this time, the infected animal is a walking “time bomb.” The symptoms of disease (irritability, frenzy, and salivation) are all important parts of the way the virus is spread among individuals. The very long incubation period allows animals bearing the disease to carry on normal activities, even breed, before the symptoms almost inevitably presaging death appear. A hypothetical viral infection that might lead to these physiological and behavioral changes but that resulted in a quick death could not be spread in such a way.