Why health experts warned of third and fourth wave of covid?

India's active caseload of covid patients has now dipped to over 13 lakh. India reports 86,498 new Covid-19 cases, 1,82,282 discharges, as per Health Ministry. In such a situation, there is hope that the second wave of coronavirus will end soon. But during the discussion on this issue, why health experts warned of the third and fourth wave of coronavirus. Watch the video to know.