The recent deaths of 24 children in Gujarat and Rajasthan have once again drawn attention to the Chandipura virus (CHPV), a little-known but potentially deadly virus that has been circulating in India for more than 60 years. While most infections cause only a mild fever that often goes unnoticed, periodic outbreaks have been linked to severe neurological illness in children, resulting in high death rates. Since the virus was first identified in 1965, outbreaks associated with it have claimed more than 300 lives.
Health experts say the recurring outbreaks highlight the urgent need for stronger disease surveillance, better diagnostic systems, increased research, and the development of vaccines and antiviral treatments.
What is the Chandipura virus?
Chandipura virus belongs to the Rhabdoviridae family and is primarily transmitted through the bite of infected sandflies. Scientists have also investigated whether mosquitoes and ticks may contribute to its spread.
The virus was first identified in Chandipura village near Nagpur, Maharashtra, in 1965, from which it derives its name. According to public health experts, Chandipura virus infection often resembles Acute Encephalitis Syndrome (AES), a condition involving inflammation or dysfunction of the brain.
Although the virus has existed in India for decades, many infections appear to be mild. Virologists believe that a large number of adults in central India may already carry antibodies against the virus, indicating they were infected earlier in life without developing serious illness.
The World Health Organization (WHO) has noted that monsoon conditions encourage the growth of sandflies and other insect vectors. It recommends controlling insect populations and protecting people from bites to reduce transmission.
Why is it considered dangerous?
The greatest concern is not the virus itself but its ability to trigger rapidly progressing neurological disease in children. In severe cases, the virus can cause acute encephalitis, a dangerous inflammation of the brain that can become fatal within a short period.
There is currently no approved antiviral medicine or vaccine for Chandipura virus. Treatment is limited to supportive care, making early diagnosis and timely medical intervention essential.
During the 2024 outbreak, India recorded 245 cases of Acute Encephalitis Syndrome between June and mid-August, resulting in 82 deaths. Laboratory testing confirmed Chandipura virus infection in 64 of these patients, making it the country’s largest outbreak in nearly two decades.
Is the virus solely responsible?
Scientists continue to debate whether Chandipura virus alone causes the severe neurological illness seen during outbreaks.
Some researchers argue that simply detecting the virus in infected children does not necessarily prove it is the only cause of the disease. They believe additional biological or environmental factors may contribute to the severe brain damage observed during outbreaks.
Investigations of earlier outbreaks have also raised questions about whether affected children suffer from encephalitis, an infection-induced inflammation, or encephalopathy, a broader condition involving brain dysfunction or swelling. This scientific uncertainty remains unresolved.
Why do outbreaks happen only occasionally?
One of the biggest mysteries surrounding the Chandipura virus is why large outbreaks occur only every few years despite evidence that the virus circulates much more widely.
Researchers suspect that several factors—including environmental conditions, nutritional status, immunity, genetic susceptibility, or other unknown biological triggers—may determine why only a small number of infected children develop life-threatening neurological disease.
Most outbreaks occur during the hot summer months and the monsoon season, when sandfly populations increase. However, scientists have not yet identified the precise conditions that trigger major outbreaks.
Why is surveillance important?
Experts believe that preventing deaths depends largely on detecting outbreaks early.
They recommend beginning surveillance before the monsoon season by monitoring insect populations, environmental conditions, and unusual fever cases. Early reporting by primary healthcare workers can help identify infected children before their illness becomes critical.
Doctors also stress the need for active surveillance, where health authorities actively search for cases, alongside stronger routine reporting systems. India has expanded its network of Viral Research and Diagnostic Laboratories, but experts say the country still requires more trained virologists, better diagnostic facilities, and increased funding for research.
Why is there still no vaccine?
Despite being discovered in India nearly 6 decades ago, the Chandipura virus still lacks a licensed vaccine.
Researchers believe one reason is that outbreaks are relatively infrequent, causing public attention and scientific interest to fade once each outbreak ends. This has slowed long-term research and reduced commercial incentives for vaccine development.
Experts argue that India already possesses detailed knowledge of the virus’s genome and structure, making vaccine development a realistic goal if sufficient investment is made. They say sustained research is needed to understand how widespread the virus is, why severe illness is rare, and what triggers deadly outbreaks.
How can people protect themselves?
Until vaccines or antiviral drugs become available, prevention focuses on avoiding insect bites.
People are advised to wear full-sleeved clothing, especially during the monsoon, use insect repellents and mosquito nets, eliminate stagnant water, and reduce breeding sites for mosquitoes and sandflies. Keeping homes and surroundings clean is particularly important in rural and peri-urban areas.
Children living in mud-plastered (kaccha) houses may face a greater risk because cracks in the walls provide ideal breeding sites for sandflies, the primary vector of the disease.
The illness typically begins with high fever, headache, and vomiting before rapidly progressing to seizures, convulsions, and altered consciousness. Once severe neurological symptoms appear, the risk of death rises significantly.
Although children have consistently been the most affected during Chandipura outbreaks, scientists still do not know exactly why they are more vulnerable. Lower immunity may play a role, but no definitive scientific explanation has yet been established.
Published on August 6, 2026
