The National Institute of Virology (NIV) in Pune, on Wednesday, confirmed that a four-year-old girl became the first fatality from the Chandipura virus in Gujarat. The death toll of suspected cases in the state has now reached 15, as the virus has spread to nearly a dozen districts.
The Chandipura virus leads to brain inflammation and swiftly escalates from flu-like symptoms to coma and death. The virus is primarily carried by the female phlebotomine sandfly.
The state’s deputy director, epidemic, department of health, Dr Jayesh Katira, told News18 that the case fatality rate or the death rate stands at 50 per cent – which means half of the suspected patients have died.
The state has up its surveillance, activated the cadre of ASHA workers to create hygiene-related awareness and trained private practitioners to swiftly handle and escalate the cases.
“There is no reason to panic as the spread is sporadic,” Katira stated, emphasising the importance of personal hygiene. “It’s crucial for people to understand that they should visit a health facility as soon as they fall ill to catch the illness early.”
Echoing similar views, India’s top virologist, Dr Raman Gangakhedkar told News18 that the virus is unlikely to cause a major outbreak. “There is no reason to panic and also, this virus is unlikely to spread rapidly as human-to-human transmission does not happen.”
“We only need to be vigilant and adopt all the preventive measures and hygiene,” he said while adding from his experience that “we have seen that the virus mainly affects children up to the age of 14 years. ”
“So far, human-to-human transmission has not been noted due to this virus, hence, we can see sporadic cases but this is unlikely to cause a major outbreak.”
Where Does The Virus Live? How Does it Transmit?
In 1965, scientists PN Bhatt and FM Rodrigues from Pune’s National Institute of Virology (NIV) discovered and named the virus after the village in Maharashtra where it was initially discovered. According to a report in the Journal of Virology, the Chandipura virus – written as CHPV in medical journals – the virus has exhibited mutations that increase its lethality in human infections.
Dr Gangakhedkar, who was the face of the country’s apex medical research body, the Indian Council of Medical Research (ICMR) during the Covid-19 outbreak, explained that this virus lives inside the tick and then transferred when the tick bites.
“So far, we have identified sandflies as the culprit for causing the infections. This virus can survive inside mosquitoes but, it is not known to transmit to humans.”
The cases are generally found in rural areas where the houses are made of stones or mud and where there are crevices in walls for the breeding of sandflies. “It is noticed commonly around rural households from where the cases are referred to hospitals in urban areas,” Gangakhedkar said. “This hasn’t been observed by other surrounding countries as much.”
How The Virus Made A Comeback After 30 Years
In 1965, an investigation of an extensive outbreak of fever during April, May, and June, in the city of Nagpur, Maharashtra, showed that the chikungunya virus was aggressively making people ill. However, the team of researchers also found dengue type 4 and one other virus.
According to the study by Bhatt and Rodrigues titled “Chandipura: a new Arbovirus isolated in India from patients with febrile illness” published in 1967 in the Indian Journal of Medical Research (IJMR), “the suggestive evidence provided by our studies that Chandipura virus is an arbovirus new to India has been not only fully substantiated but also extended by shope (Personal communication) who has shown it to be related to but not identical with Piry virus, an agent isolated in Belem, Brazil.”
For nearly three decades following the initial case, no reports of the virus emerged until it resurfaced in 2003. The 2003-2004 outbreak witnessed case fatality rates ranging from 56-75 per cent in Andhra Pradesh, Maharashtra and Gujarat with typical encephalitic symptoms. The outbreaks were devastating, bringing about 322 child deaths – 183 in Andhra Pradesh, 115 in Maharashtra, and 24 in Gujarat.
The virus garnered global attention as an emerging “neurotropic pathogen” inflicting high mortality in children within 24 hours of commencement of symptoms.
“Although it has been established as a neurotropic virus causing encephalitis, the molecular pathology leading to neuronal death is unknown,” said the study published in the Journal of Virology in 2013. This study described for the first time the mechanism of cell death in neurons after this viral infection.
Again in June 2007, the virus came back to Nagpur.
Another study published in IJMR recorded clinical manifestations where fever was the common symptom followed by convulsion (76.3%), altered sensorium (34.2%), headache (23.7%), vomiting (44.7%) and diarrhoea (23.7%). “Chandipura RNA was detected in one of two pools of sandflies from the affected locality,” the study highlighted while concluding that the “Chandipura virus was confirmed as the aetiological agent of this acute encephalitis outbreak with high case-fatality among children.”
Case Fatality Continues To Be High
Despite the advancements made in understanding the virus, Chandipura has remained a major concern in certain parts of Maharashtra and Andhra Pradesh.
“Case fatality, though reduced, still continues to occur in these areas,” said another study published by scientists at NIV in 2016. “The natural factors contributing towards the amplification of the virus leading to outbreaks are still not understood. Similarly, the host/genetic factors that contribute to high case fatality are also not clear.”
While a study in 2016 highlighted the need to develop the vaccine, no major initiative has been taken yet. “A licenced vaccine, which is the need of the hour, for vaccination of children at least in the endemic areas is still not available despite the availability of the technology.”
Experts believe that combined efforts from virologists, neurologists, paediatricians and the government are warranted to address this important issue of public health importance for minimising the recurrence of the disease.
