johannesburg. good st. louis exclusive acces hospital there. how are health care workers handling all of this? reporter: well, it is bad. we are here at a vaccine site where they are ramping up efforts to try to protect people from this more transmissible delta variant. and you mentioned that in the u.s., unvax nature ccinated pop are uniquely at risk. there are very few people vaccinated here and delta is really putting these hospitals at breaking point. they hoped that it would be better, hoped that covid-19 had done its worst. but 16 months in and mohammed and his paramedic team are in a new more dangerous fight. what has the delta variant country to covid-19? it has caused a whole lot of chaos, a whole lot of patients that are suffering.