The mRNA vaccines are highly effective in protecting against symptomatic COVID-19 among the healthcare personnel (HCPs), according to interim results from the largest COVID-19 vaccine effectiveness study conducted by the CDC. Among fully vaccinated HCPs, the two FDA-approved mRNA vaccines - Pfizer-BioNTech and Moderna - reduced the risk of becoming sick with COVID-19 by 94%.

Data for this assessment come from a network covering 500,000 HCP across 33 sites in 25 states in the US, providing additional robust evidence that mRNA vaccines are effective against symptomatic illness in real-world conditions.

In this study, the vaccination status of COVID-19 positive cases (n=623) was compared with the vaccination status of those who tested negative, who served as controls (n=1220). Comparison of the odds of COVID-19 vaccination in cases and controls was used to calculate the vaccine effectiveness estimates.

The fully vaccinated (≥7days after receipt of a second vaccine dose) HCP had 94% less likelihood of developing symptomatic illness, whereas the partially vaccinated (≥14 days after receipt of dose one through six days after dose two) were 82% less likely to develop symptoms.

These observations support the recommendation that both doses (complete vaccination) are necessary to get maximum protection.

(Source: CDC Press Release, May 14, 2021)

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA