NEW DELHI: A billion vaccine shots and counting. In less than a year since kicking off its ambitious vaccination programme, India on Thursday crossed the significant milestone of administering over 100 crore doses of Covid-19 vaccine. A mammoth achievement by all accounts, it took India 279 days to go from inoculating the very first health worker to covering crores of people across the states with a billion-plus doses. Hailing the vaccination milestone as a triumph of Indian science, enterprise and collective spirit of 130 crore Indians, Prime Minister Narendra Modi said the country has scripted history as he congratulated the citizens. India scripts history. We are witnessing the triumph of Indian science, enterprise and collective spirit of 130 c… https://t.co/jNddSGvrbo— Narendra Modi (@narendramodi) 1634792662000Here’s decoding India’s road to a billion doses … India’s cumulative vaccination doses crossed the 1 billion mark early Thursday, exactly four months after the Centre rolled out the liberalised vaccination policy and took charge of supplying doses to states. Nearly 71 crore people have been administered the first of the two doses while 29 crore have been fully vaccinated against Covid. When it comes to the adult population, almost 75% has been covered by the single dose while 31% have received both the doses. Gathering steamThe vaccination programme started off on a sluggish note in January with only a specific category of people (healthcare/frontline workers) eligible for immunisation. However, it gradually gathered pace as more people came under the vaccination ambit and manufacturers ramped up production. Since May, all those who are 18 and above are eligible for vaccination. The government is now mulling the inclusion of 12-17 age group to the drive. India took 85 days to touch the 10-crore vaccination mark, 45 more days to cross the 20-crore mark and 29 more days to reach the 30-crore mark. The country took 24 days to reach the 40-crore mark from 30-crore doses and then 20 more days to surpass the 50-crore vaccination mark on August 6. It then took 76 days to go past the 100-crore mark. The states leaderboard The pace as well as coverage rates across states vary significantly due to factors like population and on-ground roll out. However, nearly every state in India has now administered one dose to at least 60% of their population. Presently, Himachal Pradesh is the only state which has fully vaccinated over 50% of its adult population. Among the larger states, Gujarat (48.9%) and Kerala (47.8%) are not too far behind. States like Uttar Pradesh and Maharashtra, which were hit badly during the second wave in April-May, still have some ground to cover with only 19% and 31.6% population fully vaccinated against Covid. Majority vaccinated with Covishield As per data from CoWin, an overwhelming majority of people across India have been given shots of Covishield vaccine, which is the local name for the Oxford University-AstraZeneca jab that is being produced by Pune-based Serum Institute of India. Bharat Biotech’s indigenously developed Covaxin has been administered to only a fraction of the population and comprises just over 11% of the total doses given. Besides these, Russia’s Sputnik V is the only other vaccine currently in use in India. However, only a few doses has been administered so far. The worrying gap While India may have administered 1 billion vaccine doses, the milestone does mask a gap between the number of people who have been fully inoculated and those that have had just one shot. So far, India has only given two shots to 21% of its population of about 1.4 billion. By comparison, 50% have had a single dose, making it one of the highest disparities in the world. Neighbouring China, the only nation to dish out more vaccine doses than India, has fully inoculated some 1.05 billion, or 75% of its citizens, as of late September. Several hard-hit western nations like UK, US and Italy have also fully vaccinated a majority of their population. Experts worry that with a steady decline in cases, the people who have taken the first dose may skip the second one. “When cases are as low as they are right now, the level of enthusiasm and the level of urgency to be vaccinated may wane,” Brian Wahl, a New Delhi-based epidemiologist at the Johns Hopkins Bloomberg School of Public Health, told Bloomberg. While government officials have been following up with people about their second shot, it can be difficult to make them return as well as to convince those who are hesitant, said Wahl. “The further progress you make, the more challenging it is to get higher and higher levels of coverage.” Will Centre then meet its vaccination target? While the 100-crore landmark is significant in India’s vaccination journey, it still may not be enough if the government is hoping to inoculate all adults by the end of this year. At the current pace of vaccination, India will only be able to cover 76% of all its adults by December 31. The entire adult population will not be vaccinated before March 2022. In the absence of any variants of concern or threat of another Covid wave, this may not have a huge impact on the Covid situation in India. However, the Centre would still like to fulfil its ambitious target of covering all adults by the end of this year itself.