Cabinet Secretary Rajiv Gaubha has told state governments to step up the surveillance of international passengers who reached India before the government banned commercial flights from abroad from landing in the country.

Gauba, the country’s senior-most bureaucrat, said there was a gap in the number of passengers who should have been monitored and the actual number.

“This may seriously jeopardise our efforts to contain the spread of Covid-19, given that many amongst the people who have tested positive for Covid-19 so far in India have a history of international travel,” the Cabinet Secretary said in a letter to all chief secretaries on Thursday.

Gauba’s letter, accessed by Hindustan Times, did not indicate the total number of passengers who were under surveillance. But it underlined that the Home Ministry’s Bureau of Immigration had “shared details of more than 15 lakh incoming international passengers with the States/UTs for monitoring for Covid-19”.

“It is important that they are put under close surveillance to prevent the spread of the epidemic,” the letter says.

This isn’t the first time that the Centre has reminded the states about the need to keep a close watch on Indians and foreigners with a travel history. The Health Ministry has sent repeated messages to states to step up. It escalated the problem to the top bureaucrat after a lukewarm response from the states.

“I understand that the Ministry of Health has repeatedly emphasized this and requested the States and UTs to take immediate steps in this regard. I would therefore like to request to ensure that concerted and sustained action is taken urgently to put such passengers under surveillance immediately as per MOHFW guidelines,” says Gauba’s letter.

State government officials, however, contend that the Bureau of Immigration list that was sent to them often didn’t have complete and accurate information about the passengers.

In Bihar’s Muzaffarpur and Saran districts, for instance, the authorities have been able to locate only 385 of the 500 people mentioned in the Centre’s list.

“In some cases, people had mentioned their international contact numbers, which had made it difficult for us to track them… However, through our anganwadi sevikas and teachers, we have now been able to track more than 250 out of 300-odd ‘missing cases’ in our district, and only 30-odd now remain to be located,” said Saran district magistrate Subrat Kumar Se