The mother and grandmother of the10-month-old baby boy, under treatment at a private hospital in Deralakatte here for COVID-19 infection, tested negative for the virus, baffling doctors and the district health authorities.Doctors at the hospital said the condition of the infant, who was admitted with an acute respiratory infection, was stable and there had been good response to the treatment being given in isolation.Health authorities are of the view that the baby might have contracted the disease when the family travelled recently to Kasaragod in Kerala, a district identified as a hotspot for coronavirus.The family members of the baby have no recent overseas travel history.The baby, who is on the road to recovery, will be discharged if the swab results to be received were found negative and placed under home quarantine for another mandated period, health department officials said.