6 children die of suspected Chandipura virus infection in Gujarat: What is the disease, and what are its symptoms?

Here is a look at what the CHPV infection is, and who it affects.

What is CHPV infection and how is it transmitted?

CHPV is a virus of the Rhabdoviridae family, which also includes other members such as the lyssavirus that causes rabies. Several species of sandflies like Phlebotomine sandflies and Phlebotomus papatasi, and some mosquito species such as Aedes aegypti (which is also the vector for dengue) are considered vectors of CHPV. The virus resides in the salivary gland of these insects, and can be transmitted to humans or other vertebrates like domestic animals through bites. The infection caused by the virus can then reach the central nervous system which can lead to encephalitis — inflammation of the active tissues of the brain.

What are the symptoms of CHPV infection?

The CHPV infection presents initially with flu-like symptoms such as acute onset of fever, body ache, and headache. It may then progress to altered sensorium or seizures and encephalitis.

Retrospective studies from India have also reported other symptoms such as respiratory distress, bleeding tendencies, or anaemia.

The infection often progresses rapidly after encephalitis, which may then lead to mortality within 24-48 hours of hospitalisation, according to studies.

Susceptibility has largely remained limited to children below 15 years.

How can the infection be managed?

The infection can only be symptomatically managed as currently there is no specific antiretroviral therapy or vaccine available for treatment. As a result, it becomes crucial to manage brain inflammation to prevent mortality.

Disease progression can be as rapid as a patient reporting high fever in the morning, and their kidneys or liver being affected by the evening. This makes it harder to manage the symptoms, according to several paediatricians.

Which are the worst affected regions in India?

The CHPV infection was first isolated in 1965 while investigating a dengue/chikungunya outbreak in Maharashtra. However, one of the most significant outbreaks of the disease in India was seen in 2003-04 in states such as Maharashtra, northern Gujarat and Andhra Pradesh, with the three states reporting more than 300 deaths of children.

Gujarat, during the 2004 outbreak, saw a case fatality rate (CFR) of around 78% while CFR in Andhra Pradesh, during the 2003 outbreak, was pegged at around 55%.

The infection has largely remained endemic to the central part of India, where the population of CHPV infection-spreading sandflies and mosquitoes is higher.

Dr Rakesh Joshi, medical superintendent of Ahmedabad Civil Hospital and paediatric surgeon, said that the outbreaks are often reported in rural, tribal and peripheral areas, and the same may have a correlation with the prevalence of sandflies in these areas. He added that there is also a seasonal aspect to the infection where outbreaks are reported more when the sandflies’ population increases.

According to Dr Rajesh Jeswani, a paediatrician in Gujarat, “A lot of kutcha houses also use cowdung paint or maybe making cowdung cakes, which in turn attracts sandflies. Additionally, the outbreaks are more pronounced because sandflies multiply more during the monsoon season.”

Has the disease pattern changed over the years?

Yes, according to Dr Sandipkumar Trivedi, former executive board member of the Indian Association of Pediatrics. He said that there are changes in patterns being reported — both in the disease manifestation as well as the vector.

“Sandflies usually do not fly at a height more than 3 feet from the ground but this time during surveillance, sandflies have been found on terraces and higher heights. Additionally, of the six suspected deaths so far, two presented with brain haemorrhages, which is a new presentation. We are also seeing new outbreak centres, for example in Gujarat, cases are also suspected in other tribal areas such as Pavagadh, Khedbrahma and Godhra,” Dr Trivedi said.