GS Paper - 2 (Diseases)

India's R-naught value which indicates the spread of Covid-19 was recorded at 4 this week, suggesting a very high infection transmission rate, according to a preliminary analysis by IIT Madras predicting the peak of the third wave from 1 February to 15 February 2022.


  1. R-naught or R0 indicates the number of people an infected person can spread the disease to. A pandemic is considered to end if this value goes below 1.
  2. Based on preliminary analysis by computational modeling done by IIT Madras, , the R0 value was close to 2.9 nationally in the past week (December 25 to December 31).
  3. R0 depends on three things - transmissibility probability, contact rate and the expected time interval in which infection can happen.
  4. Now, with the increase in quarantine measures or restrictions, maybe the contact rate will go down and then in that case R0 can decrease.