The state had registered 19,064 new infections and 39 deaths on Saturday.
The number of samples tested for Covid-19 on January 17, 16 and 15 was 35,515, 53,876 and 64,572 respectively.
The total number of samples examined so far in the state is 2,33,62,613, the bulletin said.
The positivity rate now improved to 26.43 per cent from Sunday's 27.73 per cent.
Kolkata reported seven fresh fatalities and 1,879 new cases, 2,014 less than what the figure was on Sunday.
North 24 Parganas district recorded 11 fatalities and 1863 new positive cases.
In the last 24 hours, 11,034 coronavirus patients recovered. The discharge rate in the state now is 90.63 per cent, the bulletin said.
So far, 17,28,340 people have recovered from the disease in West Bengal.
The number of active cases decreased by 1,682 in a day to 1,58,623.
The state on Monday administered 8,78,341 Covid-19 vaccine doses, a health department official said.
Out of them, 1,03,968 doses were administered to people belonging to the 15-17 years age group while 61,903 booster doses were given to those eligible for it, he added.