Over 39,000 people have beenscreened across Assam as part of measures to prevent the outbreak of the deadly novel coronavirus, the Health and Family Welfare Department said on Wednesday.In its daily bulletin, the department said 11,975 passengers have been screened at six airports in the state till date.While 3,243 travellers were screened at three land ports -- Darranga (Baksa), Mankachar (South Salmara) and Sutarkandi (Karimganj), 24,029 persons have been screened so far at other places like rail stations and bus stands, it added."Total 634 travellers from COVID-19 affected countries have been identified and out of them, 152 passengers completed observation period of 28 days and remaining 482 are under home isolation," the bulletin said.The government has tested 31 samples so far, out of which 25 came negative and results for six are awaited."The state has strengthened the surveillance and control measures against the disease. State control room nos 6913347770/1/2/3 and 104 (Sarathi) are functional. Till today, 1,126 calls were received and information was given," the bulletin said.