Rabies

Rabies is a severe viral disease that attacks the central nervous system, ultimately causing death in almost 100% of cases once symptoms appear. The virus is found in the saliva of infected animals and is most commonly transmitted to humans through bites. In the United States, bats, skunks, raccoons, foxes, and coyotes are known carriers. Globally, however, dogs are responsible for the vast majority (up to 99%) of human rabies cases, particularly in regions with high numbers of stray dogs. The World Health Organization (WHO) highlights that rabies is a significant public health problem in over 150 countries, primarily in Asia and Africa, resulting in tens of thousands of deaths annually, with children under 15 disproportionately affected. Effective control strategies, including mass dog vaccination and improved bite prevention, are crucial to reduce this burden.

Rabies initially presents with flu-like symptoms, such as fever, headache, nausea, and vomiting, which can last for several days. These early symptoms can easily be mistaken for a common cold or the flu. As the disease progresses, more specific symptoms emerge, including: restlessness, agitation, anxiety, mental confusion, hyperactivity, difficulty swallowing (hydrophobia, or fear of water, is a characteristic symptom), excessive salivation, fear of air on the face, hallucinations, insomnia, and partial paralysis. The progression and severity of symptoms can vary considerably between individuals. The WHO notes that two main clinical forms exist: furious rabies, characterized by hyperactivity and aggression, and paralytic rabies, which involves progressive paralysis. Early diagnosis and treatment are critical as rabies is invariably fatal once neurological symptoms develop.

Seek immediate medical attention if you are bitten by any animal, or if you suspect you may have been exposed to rabies. This is particularly important if you've had close contact with a bat, even without a visible bite. A bat's small teeth can inflict a bite without your knowledge, and exposure can occur even if saliva from an infected animal comes into contact with an open wound or mucous membranes. The WHO emphasizes the importance of always seeking immediate post-exposure prophylaxis (PEP) if bitten or scratched by a potentially rabid animal.

Rabies is caused by a lyssavirus, most commonly the rabies virus itself, but other lyssaviruses, such as the Australian bat lyssavirus, can also cause the disease. The virus is present in the saliva of infected animals and is transmitted through bites, scratches, or contact with infected saliva on open wounds or mucous membranes (eyes, mouth, nose).

Several factors increase the risk of rabies infection. These include: traveling to or living in areas with high rabies prevalence (many parts of Asia, Africa, and South America), engaging in activities that bring you into close contact with wild animals (such as cave exploration or camping), working with animals or handling rabies samples (veterinarians and laboratory personnel), and having head or neck injuries. The WHO adds that the financial burden of PEP can be significant for marginalized populations.

Preventing rabies requires a multi-pronged approach. Vaccinating pets (dogs, cats, and ferrets) is a crucial step in reducing the spread of the disease, and this is emphasized by the WHO's One Health approach to rabies control. Keeping pets confined and supervised, reporting stray animals, and avoiding contact with wild animals—especially those acting strangely or unusually tame—are equally important. Securing your home to prevent bat entry is also recommended. The WHO highlights the role of mass dog vaccination programs as the most cost-effective strategy to prevent human rabies deaths. For travelers to or residents of high-risk areas, pre-exposure vaccination is strongly advised. The WHO prequalifies only three human rabies vaccines globally, underscoring the importance of vaccine quality and access.

There is no way to definitively diagnose rabies before the onset of clinical symptoms. If a bite or potential exposure occurs, your doctor will assess the situation and the potential for rabies. Testing the biting animal (if possible) is crucial. The WHO notes there are no currently approved diagnostic tools for detecting rabies before clinical symptoms appear. Post-mortem diagnosis can be done by various techniques, including the fluorescent antibody test (FAT) and RT-PCR.