Nigeria on Thursday, April 16, tested additional samples of blood for coronavirus.
Some 6,649 blood samples were tested in all.
The National Centre for Disease Control (NCDC) made this known in a tweet on Friday, April 17.
In the tweet, NCDC says there were no new cases recorded on April 16.
It says the total number of States affected in Nigeria remains 20 (19 States + FCT).
Some of the states include Lagos, Ondo, Oyo, Ogun, Edo, Ekiti, Benue, Anambra, Kano, Osun, Katsina, Enugu, Niger.