I hear many people complain that guidance about COVID-19 changes often and is frequently contradictory. That's true, but it reflects the data on which the CDC and other public health authorities base their recommendations. In essence, there are two buckets:
• Historical data
• Predictions based on modeling
Both are subject to inaccuracy for a large number of reasons — it's inevitable. As well, a given dataset may be interpreted in several ways, so we sometimes end up with profound disagreements between knowledgable experts. With that said, here are a few key points about delta:
• Historical data
• Predictions based on modeling
Both are subject to inaccuracy for a large number of reasons — it's inevitable. As well, a given dataset may be interpreted in several ways, so we sometimes end up with profound disagreements between knowledgable experts. With that said, here are a few key points about delta:
- Transmissibility appears to be significantly greater than the wild type virus and its other variants. How much higher is still being measured and debated.
- At least some of this is due to larger amounts of virus in the nasopharynx, which means people shed more when they exhale, sneeze, or cough.
- Delta may cause more severe infection, but the degree is unclear.
- Vaccinated individuals who contract delta may transmit the virus even if they're asymptomatic or minimally symptomatic. Again, the magnitude is uncertain, but if this holds up, it's a valid reason to recommend universal masking.
- The mRNA vaccines seem to protect against severe illness / hospitalization, but again, how much is unknown. Many of the vaccinated people who contract delta COVID-19 have underlying conditions.
