The number of deaths due to suspected cases of the Chandipura virus increased to 20 in Gujarat on Thursday, The Indian Express reported quoting unidentified officials.

Two deaths, both children, were reported from Ahmedabad and at least 35 persons with symptoms of the illness linked to the virus were admitted in hospitals across the state.

Only two out of the 18 samples sent by the Gujarat government for testing were confirmed cases of the Chandipura virus, the newspaper quoted an unidentified officer from the National Institute of Virology in Pune as saying.

However, unidentified district health officers told The Indian Express that the deaths of at least 20 persons were suspected to be due to the infection.

The virus, also known as the Chandipura Viral Encephalitis, is transmitted primarily by sandflies and mosquitoes, including the Aedes aegypti species that bite during the day and is also known to spread dengue. The infection can lead to encephalitis, or the inflammation of the active tissues of the brain.

Children under the age of 15 years are most susceptible to the virus. Symptoms include fever, vomiting, altered sensorium, convulsions, diarrhoea, neurological deficit and meningeal irritation.

Among the patients whose deaths in Gujarat were suspected to be due to the virus were two children from the Panchmahal district, The Indian Express reported.

While a four-year-old girl from the Kotda village in the district died on Wednesday, an eight-year-old boy from Ghoghambha had died earlier this month.

MR Chaudhary, Panchmahal’s chief district health officer, told the newspaper that both these deaths were reported to the state government.

“Since the Ghoghambha death happened much before the spread of the virus came to light, we were not able to collect samples from the patient,” The Indian Express quoted him as saying. “In the case of the child from Kotda, we have collected blood samples for testing.”

Chaudhary said that samples of sand flies had been collected from the neighbourhood of the child from Ghoghambha as it would contain the virus. The samples will be sent to the National Institute of Virology.

On Thursday, Chief Minister Bhupendra Patel reviewed the situation in Gujarat and ordered district health officers to put measures in place to curb the spread of the virus, The Indian Express reported.

The Chandipura virus was first discovered in 1965 in the blood of two individuals in Maharashtra’s Nagpur district. The virus is reported to be named after the village it was isolated from.

Outbreaks of the virus were reported between 2003 and 2004 in central India, including Maharashtra, Gujarat and Andhra Pradesh. Over 300 children died because of the infection at the time.