Tässä Gavi.org sivustolta delta-variantista:
"Other research also indicates that the vaccines may be less effective at preventing coronavirus infections in the face of the Delta variant. A recent study published in the
New England Journal of Medicine found that two doses of the Pfizer/BioNTech vaccine were 88% effective at preventing symptomatic infections, whereas the Oxford/AstraZeneca vaccine was 67% effective. A single dose of either vaccine was only 37% effective, underscoring the importance of receiving both doses.
However, COVID-19 vaccines still appear to be highly effective at preventing hospitalisation and deaths from the disease. Data from
Public Health England, where the Delta variant now accounts for most COVID-19 cases, suggested that the Pfizer/BioNTech vaccine was 96% effective against hospitalisation with Delta after 2 doses, while the Oxford/AstraZeneca vaccine was 92% effective after 2 doses."
Enää ei edes puhuta kuin "symptomatic infections". Eli kuten todettua, rokotteet estävät kiitettävänkin tehokkaasti vakavat oireet, mutta tarttuu ja leviää siitä huolimatta. Huomioitava asia on myös, etteivät oireettomat tietysti hakeudu testeihin kovinkaan helposti - näitä tulee ilmi siis lähinnä joukkoseulonnoissa yms.