My brother, wife, nephew and I went to Disneyland California the 2nd of September.  We followed the mask wearing rules and washed our hands well and often.  All four of us came down with covid-Delta variant a day after.  It started out as a runny nose and a headache.  I was vaccinated so just had a bad cold for four days but lost my smell for three weeks.  It did not go into my chest.  My brother’s family however we’re not vaccinated and all ended up on oxygen and the 53 year old parents ended up in the hospital.  My brother was intubated and flown to another hospital ICU.  After five days he started improving.  He is still in the hospital today!  Siblings are the closest related beings so this to me shows that the vaccine is working because I’m several years older than my brother and faired so much better.