The new cases were recorded in four northern provinces of Bac Giang, Dien Bien, Hai Duong and Bac Ninh.
Bac Giang registered 15 cases, including 13 that are associated with a cluster at its Quang Chau Industrial Park in Viet Yen District, which has been suspended to curb infection spread. Two other cases are those in affected areas that have been isolated.
In Dien Bien, six cases are those that have had contact with Covid-19 patients.
Two cases in Hai Duong are linked to a new hotspot in the province.
The case in Bac Ninh has had contact with a Covid-19 patient.
More than three weeks into the new wave, Vietnam has recorded 1,786 cases in 30 cities and provinces, and four patients have died.
Of the cases, Bac Giang has the highest number of infections, at 683 cases, followed by Bac Ninh with 378 cases. The neighboring provinces are home to major foreign operation plants including those of Samsung, Canon and Foxconn.