Rabies is not a particularly hardy virus when outside of its host. Just take the word of Giuseppe Lippi and Gianfranco Cervellin in "Updates on Rabies virus disease: is evolution toward 'Zombie virus' a tangible threat?" which is their piece for ACTA Biomedica, a medical journal; they state that "the rabies virus can be very rapidly inactivated by sunlight (i.e., ultraviolet rays) and heat exposure, so its chances of survival outside the host are extremely limited." A virus that can't survive UV exposure or temperature changes is already at a disadvantage when it comes to virulence, or the ability of a virus to spread. Viruses that cannot survive on surfaces for very long outside of the host are considerably less contagious than those that can survive these changes, such as Hepatitis C which sits at a survival time of three weeks outside of the host; the polio virus, which boasts three months of survival outside of the host; and the spores that cause anthrax, which can potentially live for decades in the right conditions (Steffan). Where rabies makes up for this is in its ability to survive inside of the host-- by having an incubation time that can range from two weeks to a year, and in one reported case a suspected incubation time of twenty five years, this virus leaves room for a lot of additional exposure (Mahadevan). Think about it-- if four months pass between the time you nudged a sickly skunk with your shoe and were bitten through your pants leg and the time that your symptoms begin, you might not even associate the skunk with the symptoms that you are having. If you had multiple encounters with wildlife, such as accidentally touching a raccoon that was in your dumpster or being bitten by a feral cat, you may not even remember the exact incident that exposed you to the rabies virus in the first place. During these four hypothetical months between your exposure and your symptoms, the rabid animal not only got away and continued to progress through its disease, but it also potentially infected numerous other animals before it died, creating more hosts for the harboring of this virus. Illnesses such as anthrax and polio may live outside of the host longer, but symptoms begin so quickly that these diseases are often traced to their source and stamped out before any serious havoc can be released (Steffan). The rabies virus plays the long time, which gives it more opportunity to skate by and infect others before it is caught and shut down.

This topic is huge in the argument of a virus's efficacy. If the virus enters your body and creates too big of a reaction, it can often times be immediately destroyed by your immune system before it can get so much as a sniffle out of you. This is the concept that seasonal flu vaccinations work off of; by exposing you to the strains of illness that health professionals predict will be the most problematic in your area in the upcoming season, your body trains on these strains and then is able to recognize and eradicate the virus before it can cause any sort of reaction in your body. The rabies virus does not illicit any immune response at all when its host is first exposed, and it is thus able to sneak its genetic molecules deep into the tissues of its host without being destroyed by the immune system until it replicates and becomes strong enough to begin its journey towards the spinal cord and brain (Hoagstrom). The immune response only begins after the virus has reached the meninges, which is the tissue that surrounds the spinal cord and the brain, and by the time that the immune response really begins, it is too late. The rabies virus will kill its host once it reaches the central nervous system.