The Ministry of Health documented over 11,000 domestic coronavirus cases on Sunday, along with more than 7,500 recoveries and 700 deaths.
Thirty-six provinces and cities reported 11,346 local cases, the second-sharpest daily jump, whereas another six infections were imported from abroad, the health ministry said.
A high of 13,417 locally-infected patients had been recorded on Saturday.
Almost 6,400 of the latest local cases were found in the community while the remainder were detected in isolated areas or centralized quarantine facilities.
Ho Chi Minh City recorded 4,193 of the new domestic infections, up by 109 patients; Binh Duong Province 3,795, down by 710; Dong Nai Province 849; Tien Giang Province 709; Long An Province 365; Da Nang 183; Khanh Hoa Province 160; Dong Thap Province 142; Soc Trang Province 138; Ba Ria-Vung Tau Province 107; and Can Tho City 97.
Since the fourth COVID-19 wave began in Vietnam on April 27, the country has confirmed 343,972 community transmissions in 62 out of its 63 provinces and cities.
Ho Chi Minh City is in the front with 175,994 patients, followed by Binh Duong Province with 70,242, Long An Province with 17,805, Dong Nai Province with 17,688, Tien Giang Province with 7,284, Dong Thap Province with 5,961, Bac Giang Province with 5,828, Khanh Hoa Province with 5,267, Tay Ninh Province with 4,107, Can Tho City with 3,490, Da Nang with 3,094, Ba Ria-Vung Tau Province with 2,887, Hanoi with 2,803, and Phu Yen Province with 2,434.
By comparison, Vietnam confirmed 106 community cases in the first wave from January 23 to April 16, 2020, 554 in the second from July 25 to December 1, 2020, and 910 in the third from January 28 to March 25, 2021.
The ministry announced 7,580 recoveries on Sunday, taking the total to 147,667 recovered patients.
The death toll has risen to 8,277 after the health ministry reported 737 fatalities the same day, including 599 registered in Ho Chi Minh City, 62 in Binh Duong Province, and 25 in Dong Nai Province.
The Southeast Asian country has detected an accumulation of 348,059 cases since the COVID-19 pandemic first hit it on January 23, 2020.
Health workers gave 370,836 vaccine doses on Saturday.
About 17 million vaccine shots have been administered in Vietnam since the country rolled out vaccination on March 8, with nearly 1.8 million people having been fully vaccinated.
The Vietnamese government expects to obtain 175 million shots of various vaccines, including 51 million Pfizer-BioNTech jabs, by early 2022.
It set a target of immunizing two-thirds of a population of nearly 98 million people against COVID-19 by the first quarter of next year.