New Delhi: The effective reproduction number (R) for Covid-19, an indicator of how fast the infection is spreading, has increased marginally this week to 0.92, from last week’s 0.91.
R value needs to remain under 1 for an epidemic to come to an end, but over the last two weeks the value has been increasing steadily.
Sitabhra Sinha, a researcher at the Institute for Mathematical Sciences in Chennai, calculated the R this week for India and six states with the highest number of active cases.
Sinha pointed out that for Kerala and Maharashtra — both states with the highest number of active cases — the R values crossed over 1 this week, driving up the overall R value in the country.
Last week, Kerala’s R value had dropped to 0.95. Sinha said that Kerala’s R value has been fluctuating and it was difficult to get a robust estimate for this week. But the value has increased to over 1 since 10 January.
Over a third of fresh Covid-19 cases in India are currently from Kerala. As of Friday, the state saw 66,713 active cases of Covid-19, the highest in the country.
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States see slight drop in R value
Maharashtra’s R value, which had dropped to 0.88 last week, increased to 1.08 this week. The state has 53,744 active cases of Covid-19 — the second-highest in the country.
Karnataka and West Bengal, meanwhile, also saw a rise in their R values, although both states continue to remain below 1. Karnataka’s R increased to 0.88 this week from 0.85 last week.
West Bengal saw its R value increase to 0.80 from 0.74. Uttar Pradesh, which now has the third-highest number of active cases in India, saw its R drop to 0.90 this week from 0.91 last week.
Similarly, for Chhattisgarh, R dropped to 0.78 this week from 0.79 last week.
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