In an interview to Karan Thapar for The Wire, Prof. Ashish Jha, Prof. of Global Health and Director of the Harvard Global Health Institute, said whilst the official total of Covid-19 cases in India is nearly 3.5 million if you include the unreported cases the total will be somewhere between 35 and 70 million. These figures are arrived at on the principle accepted by the Centre for Disease Control in America that for every recorded infection there are probably 10 more that are not recorded. In countries with a large population and greater population density this could be 20 unreported for every one reported case. Prof. Jha said the serological surveys done in cities like Delhi, Pune, Amritsar and parts of Bombay, which show that 30 and even 40 and in places 50% of the population has been exposed to the virus, suggest the total number of cases could be closer to 70 million.