With coronavirus cases in Bihar showing no traceable source of exposure, fear over the advent of community transmission of Covid-19 has spread across the country.



The term community transmission means that the source of infection for the spread of an illness is unknown or a link in terms of contacts between patients and other people is missing. It refers to the difficulty in grasping the epidemiological link in the community beyond confirmed cases.



However, the Indian Council of Medical Research (ICMR) maintains that there is no reason to panic at the moment. On Saturday, the ICMR announced that the medical body was changing the criteria for testing of coronavirus. India will now be switching from random sample testing to testing of all patients with severe acute respiratory infections (SARI).



As the ICMR changed the methodology, questions were raised about whether the government is worried about the Covid-19 pandemic reaching community transmission stage in India.



Refuting the possibility for the moment, Raman R Gangakhedkar, Head of Epidemiology and Communicable diseases at ICMR, said that there is little evidence to suggest social transmission has begun in India.



"We have just started testing SARI cases. There are some sporadic instances where cases have not revealed any history of exposure. But the numbers are not so exponential that we take it to mean that the virus is spreading rapidly," he said.



"It is all dependent on a person's memory and also whether they want to reveal their history or not. Some people didn't even reveal that they tested positive while others hid their travel history. Till we see a significant number of cases to indicate community transmission, let us not overinterpret things," Gangakhedkar added.



Even though the Health Ministry and the Indian Council of Medical Research (ICMR) have been insisting that there is "no solid evidence" of community transmission so far, the government has started scaling up health infrastructure to deal with any situation.



India is under a 21-day lockdown from Tuesday midnight as part of efforts to check the spread of coronavirus.



In an urgent communication, the Centre has asked all states to earmark hospitals only for treating COVID-19 patients and ramp up their capacity to manage an increasing number of cases. At least 17 states have started work on it.



Doctors at leading hospitals on Friday expressed fear that India ran the risk of seeing the viral transmission in stage three of infection if the lockdown and quarantine norms were not diligently complied with.



Dr Giridhar Gyani, convenor of a task force on Covid-19 hospitals, said there are few cases which are not known to have a link with foreign travel or direct contact of anybody who had travelled abroad.



"If such cases come in large number then we take it as the beginning of community spread. In that sense, though we are not in stage 3 but it would be better that we do all our preparations," he said.

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