A recent three-member central government investigation into increased deaths due to rabies in Kerala over the past few years, reportedly confirmed that the deaths have not been due to inefficacy of the anti-rabies vaccine.

The deaths instead can be attributed to incorrect or delayed cleaning of the animal bite wound, delay in seeking medical treatment, interrupted supply of vaccines in government primary health centres and low awareness about the implications of animal bites in the community, Dr Harikumar S, assistant director of public health in the Directorate of Health Services and Kerala State Nodal Officer for the National Rabies Control Programme, told FactChecker.

The rise in rabies deaths in Kerala became national news after a 12-year-old girl reportedly died in early September 2022, despite having received three doses of the four-dose anti-rabies vaccine course, after being attacked by a stray dog in August. She was among five such patients who died in the state despite receiving the vaccine.

The latest incident stoked a debate on the efficacy of the anti-rabies vaccine and India's rabies control measures. "Overall, 21 people have died of rabies in Kerala so far this year, of which 15 were not vaccinated. Of the six people who had received the vaccine, one was only partially vaccinated," said Dr Harikumar. The central government's investigative committee had tested the anti-rabies vaccine and confirmed its efficacy.

Rabies, a vaccine-preventable, zoonotic, viral disease, is fatal in both humans and animals once symptoms appear. Humans can get rabies if bitten or scratched by an infected animal, wild or domesticated. Rabies is endemic in India, which accounts for one in every three rabies deaths worldwide, according to the World Health Organization (WHO). Between 30-60% of reported rabies cases and deaths in India occur in children below age 15, as bites that occur in children often go unreported.

The true extent of rabies deaths in India is not known, per WHO, but the global health body said available information suggests it causes as many as 18,000-20,000 deaths every year. This is exponentially higher than the 110 rabies deaths reported countrywide in 2018, according to Ministry of Health and Family Welfare data from July 2019. The Union government does not maintain a central database of rabies cases and deaths, Dr Abi Vanak, interim director of the Centre for Policy Design, Ashoka Trust for Research in Ecology and the Environment (ATREE) in Bengaluru, told FactChecker.

Lack of responsible dog ownership, a rise in free-ranging dogs and exposed garbage are some of the notable challenges in tackling rabies, not just in Kerala but across the entire country, health experts told FactChecker.

The government must take a data-driven approach to monitor cases and deaths, manage the stray dog population and encourage responsible pet ownership, say experts. Above all, adequate trained health personnel and supplies of anti-rabies injections must be available at all times in government health centres.

How rabies affects the body

The rabies virus is transmitted to humans chiefly through the infected saliva of a domesticated (for e.g. pet dogs or cats, cattle) or wild (for e.g. bats, primates, foxes, bovines) animal. In urban settings, dogs are the main transmitters of the disease.

There are two types of clinical manifestations: paralytic and furious rabies, said Dr Harikumar. These manifestations are seen in certain phases of rabies infection. The incubation phase lasts typically for 2–3 months but may vary from a week to a year, depending on factors such as the location of the bite and viral load, per the WHO. In the prodromal phase, i.e. once the virus enters the brain, symptoms such as fever, nausea, tingling, pain, numbness near the wound and fatigue are seen. Once this phase sets in, there are no effective treatments. In the acute neurologic phase, or furious rabies phase, behavioural changes such as agitation, sudden aggressiveness, hallucinations, delirium, hydrophobia (fear of water/drinking), excessive salivation, etc, are presented). In paralytic rabies, symptoms such as fever, headaches and weakness are common. But this eventually ends in paralysis and coma, explained Dr Harikumar.

What to do if bitten or scratched by an animal

All doctors FactChecker spoke to stressed that it is vital to start post-exposure treatment as soon as possible after being bitten or scratched by a stray or wild animal, or a domesticated animal whose anti-rabies vaccination status is not known.

"Historically, a majority of rabies deaths have been among unvaccinated people. That needs to be highlighted," Dr Rajeev Jayadevan, Co-Chairman of the Indian Medical Association's National COVID-19 Task Force, told FactChecker. "Vaccines are thus far the only method of preventing rabies in case of exposure," he added.

Anti-rabies treatment starts with immediately washing the bite wound with soap. "Initial wound care is critical. In the six cases [of rabies deaths in Kerala], wound washing was only done after the patient was brought to the hospital," Dr Harikumar told FactChecker.

After cleaning the wound, the patient should visit a doctor or health centre as soon as possible to begin the anti-rabies vaccination course. The course begins with a human rabies immunoglobulin injection, which is given along with the first dose of the anti-rabies vaccine, per National Centre for Disease Control guidelines. The immunoglobulin injection is administered only once, at the start of treatment, to provide immediate antibodies to patients and prevent the entry of the rabies virus into the nervous system. Subsequent doses of the anti-rabies vaccine must be given on days 3, 7 and 14.

Some of the rabies deaths in Kerala were attributable to delayed immunoglobulin injection treatment. "In at least two [of the six rabies death] cases, there was a time gap between exposure to the animal and administration of the immunoglobulin injection. In one case, the patient came to the hospital after 6-7 hours. In another case, the patient had to travel to another hospital because the immunoglobulin injection was not available at that point of time. Time was lost there," explained Dr Harikumar. "Vaccines should also be stored at 2-4 degrees Celsius and a person needs to constantly monitor the supply chain," he added.

There have been shortages in supplies of human rabies immunoglobulin injections and anti-rabies vaccines at government health centres in the past few years, Dr Vanak of ATREE told FactChecker. "There are several issues with supply and access from the manufacturer's end with regard to Kerala's buffer stock of the vaccines, which led to dependence on Tamil Nadu for vaccines a few months back," Dr Harikumar acknowledged.

FactChecker also asked the National Centre for Disease Control whether there were shortages or interrupted supply of vaccines in government health centres anywhere in India, but did not receive a response by the time of publishing this article.

Anti-rabies treatment course depends on severity of wound and health status of animal

The location and nature of the bite wound on the body also determines the severity of exposure. "The common factor in these six cases in Kerala is all of them have severe Category III wounds, either in the face, on the lips, ear lobes, hands and palms, which are high risk areas for dog bites as they are highly sensitive with high density of nerves. If it is a rabid dog, the probability of the virus entering the nerves is high," said Dr Harikumar.

Category III is the most serious of the three categories of exposure to a suspected rabid animal, per the WHO.

Graphic: Recommended anti-rabies measures based on category of contact with animal

Categories of Contact with Suspect Rabid Animal

Measures to be Taken

Category I - touching or feeding animals, animal licks on intact skin (no exposure)

Washing of exposed skin surfaces, no PEP (vaccine)

Category II - nibbling of uncovered skin, minor scratches or abrasions without bleeding (exposure)

Wound washing and immediate vaccination

Category III - single or multiple transdermal bites or scratches, contamination of mucous membrane or broken skin with saliva from animal licks, exposures due to direct contact with bats (severe exposure)

Wound washing, immediate vaccination and administration of human rabies immunoglobulin injection

Source: World Health Organization

"When a person is bitten at a critical anatomical part which is closer to the brain, or an area which is full of nerves, the commute of the virus to the brain is shorter and faster," explained Dr Jayadevan.

Importantly, Dr Harikumar stressed that vaccination may not be necessary if bitten by an animal vaccinated against rabies, but that a doctor's opinion should be sought when deciding whether vaccination is necessary, or not. "If you've been bitten by a vaccinated dog, there is no need to panic because a vaccinated dog cannot transmit rabies. Not all minor scratches require vaccination. However, due to the variable efficacy of various anti-rabies vaccines in animals or the health status of the dog, it is recommended to visit the nearest veterinary doctor for further advice," Dr Harikumar clarified.

Other interventions against rabies

Experts said that there are three major challenges in managing the incidence of rabies in India. First is managing the stray dog population in the country. There were more than 1.53 crore stray dogs in India in 2019, a 10.6% decline in their numbers from 2012, per the 20th Livestock Census, the animal husbandry ministry informed Parliament on August 2, 2022. "While the number of strays have decreased, we will never understand the scope of the disease because no official national data has been published regarding rabies cases and deaths in recent years," said Dr Vanak.

Unlike with other diseases, the control of the population of the main host of this disease – dogs – was not under the Ministry of Health, but under various other unrelated ministries, said Dr Vanak. "The worst example of this was when the Ministry of Culture, in 2001 was put in-charge of dog population control. It is simply not feasible to sterilise and vaccinate such large numbers of free-ranging dogs in India in perpetuity," he said.

Strays have to be vaccinated against rabies year after year, as the immunity from vaccination lasts only for about a year, said Dr Jayadevan. You cannot expect a stray dog will get the next shot after a year, he added. Further, the pet and stray distinction is not black and white in India. "Abandoned, unvaccinated pet dogs or dogs that belong to gated communities wander in a 10 km radius. There are chances that the dog may give birth to a litter of puppies, who are further given away because owners cannot handle them. It is important that these dogs are vaccinated and follow-up vaccinations are done," said Dr Jayadeven.

The second challenge is that exposed garbage encourages the street animal population to grow, said Dr Jayadevan. "Exposed garbage is the only source of food for street dogs. The reason why street dogs are not in such large numbers in developed countries is because of the near absence of garbage on streets. Responsible waste management is very important in tackling this issue," explained Dr Jayadevan.

The third challenge is lack of awareness about rabies in the community. "Majority of deaths occurred because people were unaware about the seriousness of the disease and its proper treatment," said Dr Harikumar. Of 4,294 individuals surveyed in WHO's Indian Multicentric Rabies Survey in 2017, only 60.5% were aware of rabies; the rest had never heard of it. Further, only 3.7% of respondents were aware of pre-exposure prophylaxis, which is the vaccine given before being exposed to an animal bite, given mainly to those who are in close contact with animals, like veterinarians and other animal/pet handlers, per WHO.

"Ultimately, the burden of rabies can only be reduced if the focus is on a data-driven approach with authentic and timely availability of data provided by the central and state governments," said Dr Vanak.

The government can manage the stray dog population by building long-term shelters for these dogs or putting them up for adoption, said Dr Vanak. Additionally, the government can set up responsible pet ownership programmes. This includes registration and vaccination (yearly basis) of pets, neutering or spaying pets and correctly training them.

"Further, proper functioning anti-rabies clinics in rural areas is imperative. Adequate trained health personnel and supplies of antiseptics for cleaning wounds and rabies immunoglobulin injections must be available at all times."