Kozhikode, Sep 9 (PTI) Test results of 61 people who had come in close contact with the 12-year-old child who succumbed to Nipah have been negative, till now, for the virus, Kerala Health Minister Veena George said on Thursday .In a press release, the minister said samples of 15 more people in the contact list came back negative, taking the total number of people who are in the clear to 61.She also said more samples would be tested during the day and that at present 64 people were under observation at the Kozhikode Medical College and their health was stable.Later in the evening, while speaking to the media, she said presently 274 people were identified as being in the primary contact list of the victim and they were being observed.Out of them, 149 were health workers, 47 were from other districts and seven were showing mild symptoms of fever. Everyone"s health was stable, she added.She also said that the incubation period of the virus was 21 days from the date of first contact with the victim and therefore, everyone in the contact list was being monitored.Besides, a three kilometer radius around the victim"s home was a containment zone and a house-to-house survey was carried out there to find out if anyone was suffering from any unforeseen illness or had died due to unforeseen causes.She said the survey did not disclose any such unforeseen instances of illness or death and the same was good news.Eighty nine people, who had no contact with the victim, were identified with minor symptoms of fever, during the house-to-house survey and mobile labs will be used to examine them and collect their samples for testing.As of Wednesday evening the total number of people who tested negative was 46. PTI HMP ROH