RABIES: A DEADLY CONSEQUENCE OF AN INFECTED DOG BITE
The prevention of rabies starts with a basic understanding of disease transmission.
Gifty Immanuel MD, PhD, FRCP, FIDSA
Rabies is a 100% fatal disease. Rabies poses a huge share of the disease burden in India and other Asian countries. Dogs are the major vectors of the disease; occasionally, cats, wolves, and rats could also transmit the disease.
In the past two years alone, nearly 250 people have lost their lives to rabies in India. Many of the victims were vaccinated and underwent all preventive therapies. It is still a medical mystery why these people contracted the disease and died.
A host of inappropriate steps have been cited for vaccine failure. These include delayed immunization, poor wound cleansing, and forceful suturing of the wound. Whatever the reasons, several surveys indicate that the general awareness of the disease remains minuscule. Traditional healers, herbal therapies, occult or magical remedies, and ignorance compound the problem in rural areas. Victims approach medical centres only after rabies symptoms develop. By then, it is too late for any treatment to be effective. There have been few rabies survivors worldwide (through experimental therapies like the Milwaukee Protocol). However, the outcomes have not been uniformly successful.
A Historical Perspective
Rabies has been recorded in Egyptian papyrus and many ancient Indian medicine textbooks. As a clinical entity, it has been well-recognized since antiquity. Rabies also strikes fear in the hearts of people, as most victims die of severe symptoms with throat spasms while drinking water (hydrophobia). Folktales are ridden with stories of rabid humans turning into dogs or barking like dogs while dying. This is partly due to the misinterpretation of the distressing symptoms of hydrophobia.
In 1885, Louis Pasteur, the father of germ theory, discovered the first effective vaccine against rabies. This vaccine has saved many lives from the dreaded disease. Today, we have monoclonal antibodies, immune globulins, and many types of vaccines against rabies. Yet, it remains a deadly scourge and disease control remains difficult.
In tropical countries, dog vectors are responsible for more than 90 per cent of rabies cases. In colder countries, raccoons, bears, squirrels, badgers, and even bats can carry the rabies virus. Further, domestic animals that encounter infected wild animals could also become infected. Knowledge of rabies prevention might be the first step in the larger effort to control or eliminate the disease.
Prevention: The Only Cure
The prevention of rabies starts with a basic understanding of disease transmission. Any rabies-prone wound should be washed with soap and water for 15 minutes (a povidone-iodine wash can be used if available). The wound should never be sutured (unless it is infiltrated with immunoglobulin or monoclonals).
The full course of the vaccine should be followed as instructed by the medical practitioner. There should be no delay in seeking medical help. Most of the deaths have been caused by delayed vaccination.
Stray dogs and unvaccinated pets are a huge problem in the Indian subcontinent. There are serious public health initiatives to vaccinate all stray dogs, but it might take time to eliminate rabies in dogs. Rarely squirrels, cats, rats, cows, sheep, monkeys, badgers, wolves, or any warm-blooded mammal can harbour the rabies virus and transmit it through a bite. However, the decision to vaccinate and administer immunological treatments is left to the medical practitioner.
Meanwhile, cave explorers should be cautious of the possibility of acquiring rabies in the caves. For instance, some species of bats can carry the rabies virus, and while roosting, they can aerosolize the virus, which can be acquired by inhalation. In another less recognized pathway, the rabies virus can also be transmitted by transplantation of the cornea and other organs from infected donors. Understandably, all high-risk personnel, like veterinarians, wildlife biologists, animal handlers, eco-tourists, cave explorers, zookeepers, postmen, courier delivery agents, pet owners, and pet shop owners, need to be vaccinated pre-emptively. Further, they could take an annual booster based on their risk profile.
Conclusion
Rabies has been a formidable enemy, endangering human health for centuries. Nearly two centuries after Pasteur’s groundbreaking discovery, rabies is resurging at an alarming pace. The problem is quite severe on the Indian subcontinent. In the last two years, Kerala, Karnataka, and Delhi have reported the highest number of rabies deaths.
Rabies remains a neglected tropical disease and a huge public health problem. It is one of the few viral diseases that reaches 100 percent mortality. WHO reports indicate nearly 60,000 people lose their lives to rabies every year. Rabies Cure research is gaining momentum, but until we have an effective drug, primary prevention through timely wound care, vaccination, biological administration, and preventive vaccination in high-risk groups remain the main arms of prevention. Arguably, disease literacy is the most important first step in addressing rabies, an existential threat.
Bibliography
Fooks, A. R., & Jackson, A. C. (2020). Rabies: scientific basis of the disease and its management ([4th ed.]). Academic Press.
Kimitsuki, K., Khan, S., Kaimori, R., el al (2023). Implications of the antiviral drug favipiravir on rabies immunoglobulin for post-exposure prophylaxis of rabies in mice model with category III-like exposures. Antiviral research, 209, 105489.
Smith, T. G., Jackson, F. R., et al (2020). Antiviral Ranpirnase TMR-001 Inhibits Rabies Virus Release and Cell-to-Cell Infection In Vitro. Viruses, 12(2), 177.
WHO Rabies Modelling Consortium (2020). Zero human deaths from dog-mediated rabies by 2030: perspectives from quantitative and mathematical modelling. Gates open research, 3, 1564.
