At least 68 percent of Coronavirus patients in the capital, infected between the last week of May and the first week of June, had the deadly Delta or Indian variant.
The findings came in a survey conducted by the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b).
The research conducted by icddr'b found the results after genome sequencing 60 samples in 14 days.
Besides, South Afriran variant was found in second highest number of patients and few numbers of Nigerian variant were also detected, said icddr'b in a press briefing on Thursday.
Earlier on June 4, another study found that 80% of the coronavirus infections in Bangladesh are of the Delta variant, also widely known as the Indian variant.
That study was conducted by the state-run Epidemiology, Disease Control and Research (IEDCR) outfit which spoke of community transmission of the variant, and also detected an unknown strain of coronavirus in the country.
The findings were revealed at a time when spiralling virus cases are ringing alarm bells in at least eight districts in the northwest and southwest of Bangladesh. Of the districts with rising cases, Rajshahi reported 16 deaths in 24 hours until Friday morning.
The IEDCR urged people to maintain health safety guidelines to curb further spread of the Indian variant across the country.
On 8 May, Bangladesh for the first time detected six people with the Indian strain of the virus in the southwestern district of Jashore. They had all returned home from neighbouring India in recent days.
The Delta variant of coronavirus, first discovered in India, is anywhere between 30% to 100% more transmissible than the previously dominant strains, according to Prof Neil Ferguson, a leading epidemiologist at Imperial College London.
As the strain started its rounds, coronavirus infections in India soared in a "tsunami" of disease, setting a new world record for cases over the past few weeks.
The second wave hit the neighbouring country with such ferocity that hospitals ran out of oxygen, beds, and antiviral drugs. Many patients are still being turned away as hospitals are already overwhelmed.
In the face of the infection resurgence in India, Bangladesh sealed off its borders with the country. Despite the border closures, many Bangladeshis were allowed to return home with a Covid-19 negative certificate. The returnees were also put in mandatory quarantine.