The family members of the loneCOVID-19 patient in West Bengal tested negative to novel coronavirus on Wednesday but were quarantined for 14 days, a senior health official said.The 18-year-old youth, who recently returned to Kolkata from the United Kingdom, tested positive for the disease on Tuesday, making it the first such case in the state.He had gone to the UK for higher studies and returned on Sunday.The youth's mother, who is a senior state government official, his father, a doctor by profession, and two drivers were quarantined at a newly-established facility in Rajarhat area in the northeastern fringes of the city."We have also tracked 10-12 co-passengers who flew back to the country along with the youth and suggested that they be kept in home isolation. We are trying to track the other co-passengers," the official said.Doctors of the Beliaghata ID and BG hospital said the condition of the youth is stable.His mother is facing criticism on social media for her alleged lackadaisical attitude in getting the youth examined upon his return from the UK."She has flouted health department guidelines by taking her son to their south Kolkata residence on March 15 without getting him examined despite being advised by authorities of the authorities of the Netaji Subhas Chandra Bose International Airport to do so," an official said.Meanwhile, the Nadia district administration has kept eight persons in isolation after they came in contact with the father of the COVID-19 patient.The youth's father had seen patients on Monday and Tuesday, of whom eight have been identified and kept in isolation and search is on for other persons who came in contact with the doctor, officials said.Meanwhile, 95 persons who recently returned from Kerala to Rudranagar area in South 24 Parganas district have been sent for examination, sources said.On the other hand, a group of 50 pilgrims from Kerala and Rajasthan who were on their way to Ganga Sagar were stopped and sent back to Kolkata after tests were conducted on them, they said.In a bulletin, the state health department said that 15 of the 5,605 people who arrived in the city through the air and other routes on Wednesday were kept under observation.With this, the total number of passengers under observation due to the novel coronavirus outbreak rose to 17,489, it said.Swab and blood samples of seven persons admitted to isolation wards of hospitals tested negative to coronavirus on Wednesday, the bulletin said.Eight persons, who have been discharged from the hospital, have been kept in home isolation, it added.