Chennai, Dec 17 : Five more persons in Tamil Nadu have tested Covid positive with the presence of 'S' gene drop, which indicates a high possibility of the Omicron variant, taking the total number of suspected Omicron cases in the state to 13. Among the five is a woman passenger form Tamil Nadu's Arani, who reached the state from the Republic of Congo in Africa. The other four are the relatives of the person who has already been tested and confirmed positive for Omicron variant. The woman, according to health department authorities of Tamil Nadu, has been isolated and admitted to Tiruvannamalai General Hospital. The Tamil Nadu health department also informed her co-passengers, who had travelled on a Qatar flight QR 530 from Doha to Chennai on December 10. The state health department, according to officials, has traced the contact details of the Covid positive person. /IANS