Here are 10 developments in this big story:
A drop in the Covid cases - reported from across the country everyday - has brought hope as India prepares for world's largest vaccination drive set to begin on Saturday. Prime Minister Narendra Modi last week called the move "a landmark step in fighting COVID-19".
New mutant strains of Covid - being reported from the United Kingdom, South Africa and Japan - have led to fresh wave of restrictions worldwide, especially in Europe. In India, 96 such cases have been reported till yesterday.
Delhi reported lowest one-day rise in infections in eight months on Monday with 306 cases. The national capital has seen three Covid waves since the beginning of the pandemic.
The government plans to purchase a total of 5.60 crore doses of Serum Institute of India's Covishield vaccine by April 2021, at ₹ 200 per dose. While 1.10 crore doses of Covishield were purchased on Monday, there is a "commitment" to purchase another 4.50 crore doses by April 2021.
Two vaccines - Serum Institute's Covishield, developed in partnership with the Oxford University and AstraZeneca, and Bharat Biotech's Covaxin - were cleared by drug regulator DCGI about a week ago.
PM Modi held a meeting with Chief Ministers on Monday. He warned that politicians should not jump queue to take vaccine, and they should wait for their turn.
One crore health workers and two crore frontline workers will be given priority in the first phase followed by 27 crore people - those above 50 or having comorbities.
Dr Harsh Vardhan had made it clear last week that everyone in the country cannot be inoculated at this point. "Based on the quantity of doses, it is not possible to vaccinate all the people simultaneously. Hence, priority groups were decided," he had said.
The World Health Organization has warned that herd immunity will not be achieved this year despite vaccines being rolled out. "We are not going to achieve any levels of population immunity or herd immunity in 2021," WHO's chief scientist Soumya Swaminathan was quoted as saying by news agency AFP.
A WHO team is set to visit China later this week to trace the origin of coronavirus pandemic. "Understanding the origins of disease is not about finding somebody to blame. It is about finding the scientific answers about the very important interface between the animal kingdom and the human kingdom," WHO emergencies director Michael Ryan said.