The capital has extended a two-week social distancing order starting July 24 until Aug. 23 amid rising numbers of coronavirus cases.
Dung, secretary of Hanoi Party Committee, said the decision was made as coronavirus cases had exceeded 100 a day at certain points.
"Social distancing is the correct measure to keep outbreaks in the city under control," he said, adding that the majority of citizens have been closely adhering to these measures.
Besides a rising number of new infections nationwide, many cases were asymptomatic and could not be contact traced, presenting great challenges to the coronavirus fight. Certain localities have also struggled to properly manage outbreaks and allowed social distancing violations to slip through, Dung said.
Hanoi has so far observed around 10 coronavirus clusters, with over 700 community transmission cases displaying symptoms like coughing or fever detected within the city. While the social distancing period has done its job to curb infections and contain clusters, the Delta variant's high transmissibility means contact tracing efforts would be complicated, Dung said.
Most notably, clusters have been detected in high-risk areas like hospitals, factories, markets and industrial parks, which could dramatically increase the number of new cases if left unchecked, he added.
The best things Hanoi and its people could do at the moment is abide by social distancing measures while isolating coronavirus cases from the community. Clusters must be extinguished from their infancy to prevent them from metastasizing to other parts of the community, Dung said.
Ramping up vaccinations is also vital to Hanoi's battle against Covid-19, he added. Supply chains must also be kept intact to provide food and necessities to the people, he urged.
So far, the capital has enhanced its Covid-19 testing capabilities, increased its number of beds and set up ICUs, among other measures, to receive and treat severe Covid-19 patients, Dung said.
"The coronavirus fight has a long way to go, and it keeps getting harder... Without the people's support, all policies and measures would be for naught."
Hanoi has recorded 2,005 local Covid-19 cases ever since the fourth coronavirus wave hit Vietnam in late April. Several past cases were contained inside quarantine zones and other locked down areas.