Health & Fitness | Covid vaccine

Positive New Data for Johnson & Johnson Single-Shot COVID-19 Vaccine on Activity Against Delta Variant and Long-lasting Durability of Response | Johnson & Johnson

Demonstrated strong neutralizing antibody activity against the Delta (B.1.617.2) variant Persistent immune responses through at least eight months

So if J&J is so effective against Delta and many variants, why are they chomping at the bit to get pfizer or moderna into j&j recipients