Here is your ten-point cheat sheet on this big story:
India also logged the lowest number of deaths linked to the virus in a single day since May 23. 137 deaths in the last 24 hours take the country's Covid death tally to 1,52,556. Last time the number of cases in a single day was less than 10,000 was on June 11 (9,996).
580 cases of adverse reactions have been observed and seven persons have been hospitalized in three days, the government said on Monday evening, giving an update on the vaccination drive. Two persons have died also but neither deaths are related to vaccines.
In the first phase, the government aims to vaccinate 3 crore people on the frontline in the fight against the novel coronavirus. Two vaccines - Bharat Biotech's Covaxin and Serum Institute of India's Covishield - have been cleared so far by the drug controller DCGI.
Several neighbouring countries including Sri Lanka, Maldives, Bhutan have congratulated India for the historic vaccine launch. British PM Boris Johnson last month described India as "pharmacy of the world".
Maharashtra, Karnataka, Andhra Pradesh, Kerala and Tamil Nadu are the five states with the highest number of cases in the country. Among these states, Andhra Pradesh recorded the lowest number of cases in the last 24 hours with 81 new infections.
The government has released a vaccination schedule for the states across the country; big states are told to carry out vaccination four times a week and small states are expected to carry out vaccination twice a week.
A World Health Organization team in China to probe the origin of virus said on Monday that Beijing could have acted faster when Covid-19 first surfaced in China. Covid-19 was first detected in the central city of Wuhan in late 2019.
India reported its first case on January 30 from Kerala. More than 18.78 crore samples have been tested so far, the Health Ministry data shows.
Worldwide, 9.55 crore people have got affected due to the highly infectious virus so far; over 20 lakh have died.
The United States has logged 2.4 crore cases in the last one year. As Joe Biden takes oath this week, tackling of the pandemic will be his priority.