The CDC points out that:
From numerous studies conducted on rabid dogs, cats, and ferrets, we know that when the rabies virus is introduced into a muscle through a bite from another animal, it travels from the site of the bite to the brain by moving within nerves. The animal does not appear ill during this time.
The time between the bite and the appearance of symptoms is called the incubation period and it may last for weeks to months.
Once the disease becomes established, it is 100% fatal (King & Turner, 1993; Jackson, 2000). However, if treated immediately after exposure it is possible to prevent the development of the disease in most cases (Linnell et al. 2002).
The present treatment consists of a single injection of immunoglobulin (rabies antibodies grown in tissue culture) and multiple injections of rabies vaccine (Jackson, 2000). Survival of patients treated is high except in some cases where bites have been inflicted directly on the head and neck (Shah & Jaswal, 1976; Fangtao et al. 1988). This is because direct viral entry into the nerves without local replication results in very short incubation period, as occurs in cases with multiple bites in the head and neck region (Mahadevan et al. 2016).
Fangtao, L., Shubeng, C., Yinzhon, W., Chenzhe, S., Fanzhen, Z., & Guanfu, W. (1988). Use of serum and vaccine in combination for prophylaxis following exposure to rabies. Reviews of infectious diseases, 10(Supplement_4), S766-S770. https://doi.org/10.1093/clinids/10.Supplement_4.S766
Jackson, A. C. (2000). REVIEW ARTICLES-Rabies. Canadian Journal of Neurological Sciences, 27(4), 278-282. https://www.researchgate.net/profile/Alan_Jackson6/publication/12229458_Rabies/links/56f9326708ae38d710a2fa53/Rabies.pdf
King, A. A., & Turner, G. S. (1993). Rabies: a review. Journal of Comparative Pathology, 108(1), 1-39. https://doi.org/10.1016/S0021-9975(08)80224-1
Linnell, J., Andersen, R., Andersone, Z., Balciauskas, L., Blanco, J. C., Boitani, L., ... & Loe, J. (2002). The fear of wolves: A review of wolf attacks on humans. Norsk Institutt for Naturforskning https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1026&context=wolfrecovery
Mahadevan, A., Suja, M. S., Mani, R. S., & Shankar, S. K. (2016). Perspectives in diagnosis and treatment of rabies viral encephalitis: insights from pathogenesis. Neurotherapeutics, 13(3), 477-492. https://doi.org/10.1007/s13311-016-0452-4
Shah, U., & Jaswal, G. S. (1976). Victims of a rabid wolf in India: effect of severity and location of bites on development of rabies. Journal of Infectious Diseases, 134(1), 25-29. https://doi.org/10.1093/infdis/134.1.25