Rabies- A preventable zoonotic disease

Dr Thiyam Ramesh Singh *

A zoonotic disease is a disease or infection that can be transmitted naturally from vertebrate animals to humans or from humans to vertebrate animals. More than 60% of human pathogens are zoonotic in origin. This includes a wide variety of bacteria, viruses, fungi, protozoa, parasites, and other pathogens. Rabies is one of the zoonotic diseases that affect to human population.

According to, World Health Organization (WHO), Rabies is estimated to cause 59000 human deaths annually in over 150 countries, with 95% of cases occurring in Africa and Asia.

Due to under reporting and uncertain estimates, this number is likely a gross underestimate. 99% of human rabies cases are due to bites from infected dogs, more than 80% of rabies cases occur in rural areas with limited or non-existent access to health education campaigns and post-bite treatment and 4 out of 10 rabies deaths are in children.

Although it has been eliminated in Western Europe, North America, Japan, South Korea and parts of Latin America, the viral disease is still present in large parts of Africa and Asia.

India is endemic for rabies, and accounts for 36% of the world’s rabies deaths. True burden of rabies in India is not fully known; although as per available information, it causes 18000-20000 deaths every year. About 30-60% of reported rabies cases and deaths in India occur in children under the age of 15 years as bites that occur in children often go unrecognized and unreported.

In India, about 15 million people are bitten by animals. Delhi saw the highest number of deaths due to rabies in the country in 2022, as per the information given by the Health Ministry in the Lok Sabha. Dog bite incidence rate in 2022 in India was 25.2/1000 population with higher rates in urban (30.1/1000) than rural (19.6/1000) slum. As per reports, 4 individuals died in Manipur due to rabies in 2024.

What is rabies?

As per World Organization for Animal Health (WOAH), rabies is a preventable viral zoonotic disease that affects the central nervous system of warm-blooded animals including human, most often transmitted through the bite of a rabid animal. The rabies virus is particularly present in the saliva and brain of infected animals, most commonly dogs.

Bats also represent an important reservoir in certain regions. A high presence in wildlife species can create multiple opportunities for cross-species transmission, mostly affecting domestic animals and humans. Other names of rabies are Hydrophobia, Lyssa, Rage or Mad dog.

What causes rabies ?

It is caused by rabies virus which belongs to genus Lyssavirus in the family Rhabdoviridae of the order Mononegavirales. The virus has a distinct bullet shaped in structure.

What are the signs and symptoms?

After a rabies exposure, the rabies virus has to travel to the brain before it can cause symptoms. This time between exposure and appearance of symptoms is the incubation period. It may last for several weeks to several months. The incubation period may vary based on the location of the exposure site (how far away it is from the brain), the type of rabies virus, and any existing immunity. But once rabies symptoms appear the disease is invariably fatal both in animals and humans.

In animals, the first symptoms of rabies may be nonspecific and include lethargy, fever, vomiting, and anorexia. Signs progress within days to cerebral dysfunction, cranial nerve dysfunction, ataxia, weakness, paralysis, seizures, difficulty breathing, difficulty swallowing, excessive salivation, abnormal behavior, aggression, and/or self- mutilation.

In human, the first symptoms of rabies may be similar to the flu, including weakness or discomfort, fever, or headache. There also may be discomfort, prickling, or an itching sensation at the site of the bite.

These symptoms may last for days.

Symptoms then progress to cerebral dysfunction, anxiety, confusion, and agitation. As the disease progresses, the person may experience delirium, abnormal behavior, hallucinations, hydrophobia (fear of water), and insomnia.

The acute period of disease typically ends after 2 to 10 days. Once clinical signs of rabies appear, the disease is nearly always fatal, and treatment is typically supportive. Less than 20 cases of human survival from clinical rabies have been documented. Only a few survivors had no history of pre-or postexposure prophylaxis.

How is rabies diagnosed?

Clinical history and behavioural changes are some of the important criteria to diagnose the disease. In animals, rabies is diagnosed using the direct fluorescent antibody (DFA) test, which looks for the presence of rabies virus antigens in brain tissue. In humans, several tests are required.

Rapid and accurate laboratory diagnosis of rabies in humans and other animals is essential for timely administration of postexposure prophylaxis. Within a few hours, a diagnostic laboratory can determine whether or not an animal is rabid and inform the responsible medical personnel. The laboratory results may save a patient from unnecessary physical and psychological trauma, and financial burdens, if the animal is not rabid.

In addition, laboratory identification of positive rabies cases may aid in defining current epidemiologic patterns of disease and provide appropriate information for the development of rabies control programs.

What are the treatments to be given ?

Clinicians faced with treating clinical rabies patients can either offer supportive therapy or an aggressive treatment plan. There is no single effective treatment for rabies once clinical signs are evident.

What measures can be taken up to prevent?

1. Vaccinate your pets. Cats, dogs and ferrets can be vaccinated against rabies. Ask your veterinarian how often your pets should be vaccinated.
2. Keep your pets confined. Keep your pets inside and supervise them when outside. This will help keep your pets from coming in contact with wild animals.
3. Protect small pets from predators. Keep rabbits and other small pets, such as guinea pigs, inside or in protected cages so that they are safe from wild animals. These small pets can’t be vaccinated against rabies.
4. Report stray animals to local authorities. Call your local animal control officials or other local law enforcement to report stray dogs and cats.
5. Don’t approach wild animals. Wild animals with rabies may seem unafraid of people. It’s not normal for a wild animal to be friendly with people, so stay away from any animal that seems unafraid.
6. Keep bats out of your home. Seal any cracks and gaps where bats can enter your home. If you know you have bats in your home, work with a local expert to find ways to keep bats out.
7. Consider the rabies vaccine if you’re traveling or often around animals that may have rabies. If you’re traveling to a country where rabies is common and you’ll be there for an extended period of time, ask your doctor whether you should receive the rabies vaccine. This includes traveling to remote areas where medical care is difficult to find.

A major step to eliminate rabies

A Global strategic plan to end human deaths from dog-mediated rabies by 2030. Dog-mediated human rabies can be eliminated by tackling the disease at its source: infected dogs. Making people aware of how to avoid the bites of rabid dogs, to seek treatment when bitten and to vaccinate animals can successfully disrupt the rabies transmission cycle.

For the first time, WHO, the UN Food and Agriculture Organization (FAO), the World Organisation for Animal Health (OIE), and the Global Alliance for Rabies Control (GARC) are joining forces to support countries as they seek to accelerate their actions towards the elimination of dog-mediated rabies by 2030.

The Global Strategic Plan set three objectives for affected countries, development partners, and key stakeholders:

(1) to effectively use vaccines, medicines, tools, and technologies that will stop dog rabies transmission and reduce the risk of human rabies deaths;
(2) to generate evidence-based guidance and high-quality data to measure impact and inform policy decisions; and
(3) to harness multi-stakeholder engagement to sustain commitment and resources.

Since rabies symptoms can greatly vary from one animal to another, the only way to confirm a case of rabies is through laboratory testing. In-country capacity to handle samples and master laboratory techniques is a key link in the fight against this deadly disease. To help Members improve their diagnostic capacity, WOAH established the Reference Laboratory Network for Rabies (RABLAB) in May 2021.

This network aims to improve the prevention and control of rabies worldwide through the development and standardisation of laboratory techniques, as well as the coordination of research and training activities. RABLAB is composed of a diverse group of laboratories from around the world which provides a platform for collaboration, sharing of knowledge and expertise, and for the development of innovative approaches to eliminate dog-mediated rabies.

In India, Ministry of Health & Family Welfare and Ministry of Fisheries Animal Husbandry & Dairying, Government of India jointly launched ‘National Action Plan For Dog Mediated Rabies Elimination (NAPRE) on 28th September 2021 from India by 2030’.

The Animal Welfare Board of India (AWBI) has also requested the concerned authorities to take appropriate action and to effectively implement the Animal Birth Control (Dogs) Rules, 2023 to control the dog population. The Sikkim Anti-Rabies and Animal Health (SARAH) program is the first State-wide rabies program in India and demonstrates a successful One Health model of dog-mediated rabies elimination.

Key components of a successful National control programme for dog-mediated rabies

1. Surveillance and reporting to monitor the disease trends and detecting potential new cases as early as possible.
2. Mass dog vaccination campaigns to tackle the disease at its animal source. Vaccinating at least 70% of dogs in at-risk areas can reduce human cases to zero.
3. Effective control of dog populations to reach a rabies immune or rabies-free dog population, while ensuring that animal welfare is respected.
4. Public awareness and education campaigns to improve the understanding of the risks related to rabies, as well as how to prevent them.

Mexico has been the first country in the world to obtain WHO validation for eliminating dog-mediated human rabies as a public health problem. Dog mediated rabies has been eliminated from Western Europe, Canada, United States of America (USA), Japan and some Latin American countries.

In India, Goa had maintained a rabies-free record among humans since 2018, achieving a remarkable feat by recording zero cases of people contracting the dreaded disease after being bitten by dogs. This success continued through 2019, 2020, and 2021, leading to its designation as India’s first rabies-controlled state.

This is a brief idea about rabies. To know more about this disease, you can refer more articles, news, and journals.