India reported a record increase of nearly 70,000 new coronavirus cases on Wednesday. Meanwhile, a new study released on Thursday shows millions more could have caught the virus. Delhi's Health Minister Satyendra Jain said blood tests on 15,000 residents conducted earlier this month found nearly 30 percent of them had COVID-19 antibodies. A similar survey from June to July also found 23 percent of the city's residents had been exposed to the virus. But as Dr. Vikas Bajpai, an expert in community health suggests, developing antibodies is necessary for developing immunity, but it doesn't mean the capital is getting closer to herd immunity.