Rabies is a viral disease that causes severe inflammation of the brain and spinal cord in humans and other mammals. Historically, it was often referred to as “hydrophobia” due to the intense fear of water experienced by affected individuals. This serious public health concern is present in over 150 countries across all continents except Antarctica. Rabies continues to be nearly universally fatal once clinical symptoms become apparent.
The Grim Reality of Rabies Fatality
Once clinical symptoms of rabies manifest, the disease is considered virtually 100% fatal. Mortality rates are often described as almost 100% or over 99% once symptoms appear.
Globally, rabies is estimated to cause around 59,000 deaths each year, with approximately 40% of these fatalities occurring in children under the age of 15. Over 95% of these human deaths are concentrated in Africa and Asia. In up to 99% of human rabies cases, the virus is transmitted through the bite or scratch of an infected dog. Without prompt medical intervention after exposure, death is almost certain.
Why Rabies Infection is So Lethal
Rabies is caused by the rabies virus. Following transmission, typically through the saliva of an infected animal, the virus initially replicates in muscle tissue near the entry site. From there, it infiltrates the peripheral nervous system.
The virus then travels along nerve pathways to reach the spinal cord and eventually the brain. This progression can take weeks to months, influenced by factors such as the bite’s proximity to the central nervous system and the amount of virus introduced. Once the virus reaches the brain, it rapidly multiplies, causing severe and progressive inflammation, a condition known as encephalitis.
The extensive infection of neurons throughout the central nervous system leads to irreversible neurological damage. This widespread disruption of brain function ultimately results in death, commonly from respiratory failure, cardiac arrest, or other complications like severe laryngeal spasms or seizures. A key factor contributing to rabies’ nearly universal lethality is the virus’s ability to largely bypass the immune system once it establishes itself within the central nervous system, partly by preventing immune cells and antibodies from effectively crossing the blood-brain barrier.
Understanding the Rare Instances of Survival
Survival from symptomatic rabies is an extremely rare occurrence. As of recent reports, there are approximately 34 well-documented human survivors globally.
The “Milwaukee Protocol” is an experimental treatment strategy that gained attention following the survival of Jeanna Giese in 2004. She became the first known person to survive rabies without having received post-exposure prophylaxis before the onset of symptoms. The protocol generally involves inducing a therapeutic coma and administering antiviral drugs. The premise was to suppress brain activity, theoretically minimizing damage, while allowing the patient’s immune system to mount an effective response against the virus.
Despite initial optimism, the Milwaukee Protocol has demonstrated limited success in subsequent applications, with numerous documented failures. Its effectiveness remains a subject of considerable debate, and many experts now advocate for its abandonment due to its high failure rate and potential for severe adverse effects. In the few instances of survival, factors such as intensive supportive care, a less aggressive viral strain, or a particularly strong immune response are thought to have contributed to recovery. Even among those who survive, severe neurological impairments and a reduced quality of life are common outcomes.
Preventing Rabies: Your Best Defense
Rabies is nearly 100% preventable through timely and appropriate interventions, particularly Post-Exposure Prophylaxis (PEP). This immediate medical response is designed to stop the virus from reaching the central nervous system after a potential exposure. PEP involves three components that work together to provide protection.
The first step in PEP is immediate and thorough wound care, which involves washing the bite or scratch with soap and water for at least 15 minutes. This action physically flushes out viral particles from the wound site, significantly reducing the risk of infection. Following wound cleansing, rabies immunoglobulin (RIG) is administered. RIG provides immediate, passive immunity by directly neutralizing the virus at the wound, offering protection until the body can develop its own active immune response.
The final component of PEP is a series of rabies vaccine doses, typically four doses administered over a 14-day period for previously unvaccinated individuals. This vaccine stimulates the body to produce its own antibodies, providing long-term protection. When administered promptly after exposure and before symptoms appear, PEP is highly effective, virtually ensuring survival.
Beyond emergency post-exposure care, pre-exposure vaccination (PrEP) is a proactive measure for individuals at high risk of rabies exposure. This includes professionals like veterinarians and animal handlers, as well as travelers visiting regions where rabies is common. While PrEP simplifies future post-exposure treatment by often negating the need for RIG, it does not eliminate the requirement for medical evaluation and booster vaccine doses following a potential exposure. Comprehensive public health efforts, such as mass vaccination campaigns for domestic animals—especially dogs—and educating the public on avoiding contact with wildlife, are also fundamental in preventing rabies transmission.