New Delhi: In India, each person infected with COVID-19 is passing the virus to only 1.7 people on an average, which is much lower than most countries, researchers have found.
This could account for the relatively slow increase in coronavirus patients in the country compared to Italy, Iran and US, which have witnessed unprecedented spread of the virus.
A study by scientists Soumya Easwaran and Sitabhra Sinha at the Institute of Mathematical Sciences in Chennai has found that COVID-19 has an R0 — R-naught or reproduction number — of 1.7 in India, a report in The Indian Express said.
R-naught is the reproduction number of the disease that highlights the number of people a patient directly infects.
In China’s Wuhan city, where the first case of the novel coronavirus was reported, the R0 was 2.14. It was 2.73 in Iran and 2.34 in Italy.
When R0 for a disease is below one, it is unlikely to turn into an epidemic.
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Figure is likely to change
However, the reason for a low R0 in India could not be immediately explained by the researchers.
“Right now, we do not know the exact reason for low R-naught. Maybe a week from now on, when the impacts of government measures start getting reflected in the data, we would have some idea,” Sinha told The Indian Express.
Moreover, the figure is likely to change in the coming days depending on whether the government measures to curb the spread of the disease prove to be successful.
The team believes that climatic conditions may play a role in the low reproduction number in India as the distance of a country from the equator might have a correlation with how fast the virus was spreading.
“If we plot the R0 numbers of other countries against the latitudes in which they are situated, India more or less fits into the curve,” Sinha said.
However, the team did not find any evidence that temperature plays a role in how fast COVID-19 spreads. Sinha said they are unable to explain the correlation between latitude and reproduction number as of now.
Research from other countries seems to suggest that higher temperatures and humidity can slow the spread of the virus.
A study by researchers from Spain, Portugal and Finland, which is yet to be peer-reviewed, found a significant correlation between climate conditions and outbreaks. They found that in extreme cold as well as in very hot and humid conditions the virus is “largely absent”.
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