KOLKATA : Covid symptoms have been milder and undergone subtle changes during the second wave along with a much higher transmission rate, often making it difficult to identify the virus, according to doctors in Kolkata.
While cough, cold and fever had been the most common symptoms during the first wave, weakness, body ache and mild diarrhoea have been more frequent this time.
The reason could be that more younger people with stronger immunity have been affected resulting in non-lung symptoms, they said.
“While the virus is more transmissible this time with a lower mortality rate, there has been a paradigm shift in the mean age of the affected population — from 59-60 last time to less than 45 now. Being more mobile, the younger population has been affected but due to their stronger immunity, the virus is often not being able to penetrate the lungs. So the non-lung portions are being affected, resulting in symptoms like tiredness, fatigue, lethargy and body ache. Cold and fever have been absent in 10%-15% of cases, which makes it a challenge to diagnose. Non-specific symptoms like diarrhoea, vomiting and even stomach ache have been widespread this time,” said Raja Dhar, director of pulmonology at CMRI Hospital.
Since the younger population has been more affected during the second wave, thanks to the elderly being vaccinated, recovery has so far been quicker and easier. But since transmission rate is much higher — the state has already crossed last year’s peak in terms of daily new cases — even a mortality rate of 1% could lead to a large number of casualties, doctors warned.
The younger population has so far fought the virus well, according to Peerless Hospital microbiologist Bhaskar Narayan Chaudhuri.
“Due to their stronger immunity, the symptoms have been mild, almost unrecognizable in many cases. But with the number of affected being very high, casualties could be very high even if just 1% of cases turn serious,” said Chaudhuri.
Fortis Hospital internal medicine consultant Joydeep Ghosh agreed.
“Persistent diarhhoea and headache have been very common this time. Fewer have had fever or cough, which made it easy to identify Covid last time. Vaccination has protected the elderly population and since we are still at the beginning of the surge, it’s too early to say it’s less fatal this time. But the symptoms have got milder,” said Ghosh.
Viruses tend to be less aggressive during second and subsequent waves, said Chaudhuri. “In natural course, they turn less virulent to survive but get more transmissible. This seems to have happened leading to changed symptoms,” said Chaudhuri.
A reason why a substantial number of patients have not turned serious is the earlier use of steroids, Chaudhuri pointed out. “Last time, it had been delayed, leading to death in many cases,” he said.