The third wave of Covid-19 cases is rising at a faster rate than in the previous two waves, shows official data -- raising the stakes for the public to strictly follow the health guidelines.

In the 24 hours till 8:00am yesterday, the positivity rate was 17.82 percent, according to the Directorate General of Health Services (DGHS).

Eight days earlier, the positivity rate was about 7 percent.

It took half a month from March 14 to March 29 for the positivity rate to spike by the same percentage points during the first wave between March and May 2020, caused by the Beta variant, a milder form of the deadly Delta variant.

During the second wave caused by the Delta variant between June and September last year, it took about a month from May 15 to June 18.

The trend indicates that the Omicron variant is spreading three times as fast as the Delta variant.

"There is no room for complacency thinking that Omicron poses a less severe threat than the other variants -- our reality is not the same as in Europe, where the vaccination rate is very high," Mushtuq Hussain, consultant of the Institute of Epidemiology, Disease Control and Research, told The Daily Star yesterday.

Bangladesh has targeted to inoculate about 80 percent of its population with two doses of the Covid-19 vaccine. As of January 13, 40.65 percent of the target has been met, meaning 32.5 percent of the population has been vaccinated.

The number of vaccine recipients is less than the number that has signed up for the jabs, said DGHS spokesperson Nazmul Islam.

Vaccinated patients are more likely to experience milder disease if infected by the Omicron variant, while a booster dose is said to provide bigger and broader protection against the rogue variant.

Only 0.11 percent of the population has received the booster dose as of January 13.

"Taking the Omicron variant lightly is a dangerous approach," Hussain said, adding that the variant may continue to infect more people over the next two months.

It appears that the residents of Dhaka are taking the matter lightly: of the 32,172 cases reported in the first 16 days of January, 73 percent were in the Dhaka district.

Some 5,222 new cases were reported in the 24 hours to 8 am yesterday -- the highest in six months -- and about 77 percent of the cases were in the Dhaka metropolitan area.

According to the division-wise list of the DGHS, the Dhaka division had a 14 percent bed occupancy rate in Covid-19 hospitals yesterday, while it was 13 percent in Chattogram.

Meanwhile, 22 more Omicron cases have been reported in the country, raising the total number of cases to 55.