dramatically this month. look at that graph there, they've started coming down. a senior researcher at the south african council for scientific and industrial research tells cnn the country is past the peak already of the omicron wave. so let's go now to johannesburg, south africa, and an epidemiologist. portia, thanks so much for joining us. can you explain why new infections are already dropping, based on these numbers? >> thank you for having me. so basically, since the 24th of november when the omicron variant was discovered, we saw a real steep increase in the number of cases, much higher than what we had seen with the delta variant, basically because the virus seems to be more transmissible, more infectious. and it seems to also cause infections even in people who have previously been infected