The state has started surveillance of mobile phone data of novel coronavirus positive cases and those under home quarantine to track their location.

Jharkhand health minister Banna Gupta told The Telegraph that the state has emulated what has already been done in Delhi and Kerala — using mobile phones for contact tracing of confirmed and suspected cases of novel coronavirus infection.

“We started doing this as soon as the first case was detected in Ranchi and we are also using the technology to track those under home quarantine. The health department, police and telecom service providers are collaborating with each other in this effort,” said Gupta.

Principal health secretary Nitin Madan Kulkarni said the police and health department officials have succeeded in contact tracing of the four positive cases, including the latest confirmed case from Ranchi.

“We are using the technology at our hand with help of the police department to trace the contacts using mobile phones of the affected persons and we have achieved good success in this direction. We are also planning to use it for those kept under home quarantine too,” said Kulkarni.

A senior police officer, who has been training the technical cell in all 24 districts, explained the process.

“It is nothing new, and we have been doing it successfully in case of fugitive criminals,” said the Ranchi-based officer. “All mobile service providers store for a specific period data relating to the use of each mobile phone on their network including location information.

“For anyone who tests positive for Covid-19 this data could be used to list every location where the patient (more accurately, the phone) had been during the last few weeks,” he added. “It would then be possible to identify every phone that had been in close proximity to the person’s phone. The owners of those phones could then be tested, even though they may not necessarily have developed symptoms or suspected that they had come into contact with a coronavirus positive case.”

Sources in the integrated diseases surveillance program (IDSP) commonly known as surveillance unit functioning under state health department said the government was also toying with idea of assembling locations of all positive cases into a single, searchable database that could then be cross-referenced against the locations of known clusters of infection.

This would allow contact tracing throughout the entire population, creating a more proactive way to track down suspected cases, the sources said.

As of Sunday (April 5), 14,228 persons were at quarantine centres across the state while 1,43,227 were under home quarantine.