The three localities with the highest number of new cases were Hanoi with 970 cases, northern Yen Bai Province with 424 cases, and northern Vinh Phuc Province with 302 cases.
Of the day's tally, 6,245 cases were detected in the community.
The Covid-19 death toll in Vietnam rose to 43,016 with the confirmation of nine deaths Sunday.
The Health Ministry also confirmed 4,581 recoveries the same day, bringing the total number of recovered cases so far to 9,086,075.
Over 77.4 million people of Vietnam's 96 million population have been vaccinated with two doses, and more than 52.3 million have received the third dose.