As per the latest Covid-19 bulletin, Delhi on Saturday had a case positivity rate of 24.56 per cent. In other words, every fourth person in the city whose sample was taken has tested positive for the viral disease. Chief Minister Arvind Kejriwal said the situation had become 'very serious and worrisome', with oxygen stock, remdesivir and tocilizumab drugs in short supply. Kejriwal appealed to the Centre to increase the number of Covid beds at hospitals run by it. Watch the video.