One of the biggest part of the slowdown is communication between private companies which want to bring vaccines to the market and public agencies which want to

One of the biggest part of the slowdown is communication between private companies which want to bring vaccines to the market and public agencies which want to make sure that it is safe. To make sure that this is done most effectively, the US government announced "Operation Warp Speed" back in May which has helped private and public organizations work very effectively.