Covid-19: Third wave in Kolkata sees fastest rise & fastest dip

KOLKATA: The third Covid wave has seen the quickest surge and fall in daily new cases in Kolkata with the number of affected rising eight times in just 11 days and sliding back over the next 13 days. This was far sharper than the surges witnessed during the peaks of the first and second second waves.
During the second wave last May, the city had seen cases rise ten times over a period of a month-and-half and it had taken more than a fortnight for the number to slide back significantly.

The number of fresh cases was far less during the second wave.
The peak of the first wave in October, 2020, had seen daily cases crawl to its highest over a period of nearly a month-and-half.
In Bengal, daily cases surged 12 times between December 30, 2021 and January 9 when the state reached the peak of the third wave with 24,287 cases.
While Kolkata recorded 1,090 new cases on December 30, 2021, it jumped to 4,759 on January 4 and to 8,712 on January 9 - the city's highest single-day spike during the current wave. By January 15, the number had dropped to 4,831 and to 973 on January 23.
During the first wave, the rise was very small in terms of numbers with Kolkata recording a highest of 910 cases on October 25, 2020.
The second wave had seen a staggered surge, too, with fresh cases rising from 399 on April 1 to 3,995 on May 14 - the highest recorded during the wave.
The reason behind the sharp and quick rise and fall in cases this time is a more transmissible virus that has affected more in a quicker time with a very short incubation period, said experts. While it would take 4-6 days for an infected person to show symptoms during the first two waves, it was reduced to just a day this time, they said. "Also, symptoms have been mild and muted that have helped transmission since a few realized that they have an infected person at home. Entire families have got infected even before they had pronounced symptoms. It has often been too late before symptoms showed up and an infected individual went into isolation," said Peerless Hospital microbiologist Bhaskar Narayan Chowdhury.
RN Tagore International Institute of Cardiac Sciences (RTIICS) intensivist Sauren Panja agreed.
"The rate of infection has been far higher this time and a majority of the cases have not been diagnosed at all. Most have chosen to skip test and hence not stayed in home isolation. They have spread the virus to others, helping a quick surge in the number of affected," he said.
A sharper and shorter spike has been the trend around the world during the current wave, pointed out pulmonologist Raja Dhar.
"Omicron is a far more infectious but mild variant that has led to a quicker surge but faster recovery. So, we have seen a dramatic rise in numbers, a quick plateauing of cases followed by a decline," said Dhar.