Seven Indian airports have been placed on an Ebola virus alert on Friday, just days after a passenger from Liberia was quarantined at New Delhi International airport, NDTV, a local news network, reported, citing government officials. The airports will follow a protocol that is already in place at 18 other airports in the country.

Airports at Varanasi in northern India’s Uttar Pradesh, Gaya in Bihar, Vishakapatnam in the southern state of Andhra Pradesh, Nagpur in the western state of Maharashtra, Bagdogra in eastern India’s Assam as well as two other airports in the country, were the ones to be put on a fresh Ebola alert on Friday. These airports will now screen passengers returning from Ebola-hit countries for signs of the deadly virus, which has killed over 5,000 people so far, mostly in West Africa.

Last week, India had quarantined a 26-year-old man, who had been cured of Ebola in Liberia and was returning to New Delhi. Blood samples taken from him tested negative, but officials isolated him after traces of Ebola were found in his semen. The man was released from a hospital in Liberia on Sept. 30 and was termed cured.

“It was a case of high risk patient who had already undergone treatment for Ebola. When he came to India, he was kept under observation. That person is kept in isolation and situation is being closely monitored. We are cautious and there is no need to panic. The situation is under control,” J.P. Nadda, the country’s health minister, had said Tuesday, according to NDTV.

In August, India had isolated six Indian nationals returning to New Delhi from Liberia. Their samples had later tested negative for the virus.