Emergence of rabies among vaccinated humans in India: a public health concern

Rabies is transmitted through the bite of animals infected with rabies, primarily dogs. Globally, dog-mediated rabies causes an estimated 59,000 human deaths annually.¹ According to WHO, India accounts for 36% of the global deaths due to rabies. India also accounts for 65% of the deaths due to rabies in the South-East Asia region. The National Rabies Control Program reported 6644 clinically suspected cases and deaths of human rabies between 2012 and 2022. In India, the sudden spike in the number of cases of rabies is a major public health concern. Deaths due to rabies among vaccinated and unvaccinated individuals, especially in the State of Kerala, have caused great public concern.² In Kerala, the number of infected dogs has doubled in the past five years. Among 300 samples taken from dogs, 168 samples (56%) were found to be positive for rabies, compared to 32% in a similar study conducted in 2016.³ The state has reported more than 200,000 dog bite cases and 21 deaths (12 deaths were laboratory confirmed), which is almost double the deaths reported during the last year.² Six of the victims, including a 12-year-old child, died despite receiving anti-rabies immunoglobulin (RIG) and vaccine.² Due to a severe shortage of vaccines resulting from an increase in rabies cases, 250 anti-rabies vaccines were allegedly administered without being subjected to the required quality tests.⁴ However, the authorities later obtained a letter from the manufacturing company alerting them of the completion of quality inspections and the certificate from Central Drugs Laboratory (India). Antibodies against rabies were later detected in one of the six victims.^5,6 Till now, the expert panel constituted to investigate deaths has not reported any concern regarding the effectiveness or potency of biologicals or the emergence of rabies virus strains that evade the protective effects of vaccine.^7,8 Unfortunately, the neighbouring state of Tamil Nadu has also reported an alarming number of deaths from rabies. The disease has claimed the lives of 18 people in the last eight months which is of major concern.

The current rabies crisis in many countries including India is not controlled because stray dogs and other rabid animals roam freely and attack people. Local municipalities need to be strengthened in terms of resources and funding in the development of effective control measures. Concerns have been raised about the mismanagement of street dogs in terms of disruption in vaccination and birth control activities during the COVID-19 lockdown.⁹ In India, an increase in aggression among dogs has been observed post-pandemic (Fig. 1), probably resulting from food shortages, abandonment of pets, and a decrease in human–dog interaction.^8,9 The inaction of the authorities would lead to people harming innocent dogs not involved in any attack on humans. Despite the Prevention of Cruelty to Animals Act of 1960, which protects stray animals, and the Animal Birth Control (Dogs) Rules of 2001, which makes it illegal to remove or relocate dogs, mass killing of dogs have been reported. The government should develop more stringent policy measures to protect innocent stray animals. The Supreme Court of India directed the State of Kerala to take strict measures after a public interest litigation (PIL) was filed. Animal rights activists allege an inefficient implementation of the Animal Birth Control (ABC) program and vaccination of pet and stray dogs as the main issues for the rising dog menace.

Fig. 1.

Choropleth map showing dog-bite cases in the states and Union Territories of India between January–October 2022, as reported by local media reports. The map was created using QGIS 3.26.3. The base layer map was used from Survey of India.

Rabies is a vaccine-preventable disease. India currently follows the updated Thai Red Cross Schedule for intramuscular (IM) and intradermal (ID) vaccination. The current regimen for post-exposure prophylaxis (PEP) includes eight ID doses (two sites per visit on days 0, 3, 7, 28) or five IM doses on days (0, 3, 7, 14, and 28).¹⁰ Improper or non-administration of RIG or poor wound management provides more time for the virus to spread. Despite receiving the proper PEP, an unfortunate outcome might be possible. After the vaccine is administered, it is a race between the body to produce antibodies and the virus to reach the brain. It has been suggested that when parts of the body rich in nerves or close to the brain are affected, the vaccine would not have sufficient time to act.¹¹ Hence, the vaccine alone is not sufficient to prevent rabies in category III exposure, and RIG must be given for passive immunity as soon as possible. In rare cases, instances of cold chain failure and substandard or fake vaccines, have also been documented.

In Kerala, rabies deaths among vaccinated individuals were due to the nature of wounds and failure to seek prompt care. Awareness about first aid measures after an animal bite in the country is inadequate. In a survey in six Indian states, only 38% of victims of animal bites reported washing wounds after biting with soap and water.¹² WHO recommends flushing and washing the wound with water, soap, detergent, povidone-iodine, or other virucidal agents for a minimum of 15 min. Preexposure prophylaxis (PrEP) should be advocated for high-risk populations and children having less access to PEP and where incidence of dog bite is greater than 5%. Surveillance should be implemented to differentiate between rabies-infected and noninfected dogs, and infected ones need to be managed accordingly. Effective mass media campaigns are required to educate the public about rabies, first aid measures, and the importance of seeking timely care.

Considering the increase in animal bite cases and rabies deaths, Kerala should consider using PrEP as a temporary measure until canine control is achieved. All children in endemic regions must also be provided PrEP. Cross-state sharing of vaccines and RIG during the crisis period should be adopted. The availability of critical supplies should be displayed on e-Portals such as e-RaktKosh in various hospitals in endemic regions. To keep dogs off the streets, it is also important to promote the adoption of street dogs and enforce strict regulations on pet ownership. In summary, there is a need for integrated and comprehensive management of street dogs and bite management.

Contributors

B.K.P., P.S., K.G. and A.K.A. conceptualised the study. A.S. and P.S. wrote the first draft of the manuscript. P.K. curated the data and prepared the choropleth map. R.S., A.K.A. and B.K.P. edited the draft. All authors reviewed subsequent versions and approved the final version of the manuscript.

Editor note

The Lancet Group takes a neutral position with respect to territorial claims in published maps and institutional affiliations.

Declaration of interests

None.