Back to Blog
Margaret Keenan becomes the first person in the world to receive Pfizer’s Covid-19 vaccine. While this is very encouraging, the success of any vaccine is greatly dependent on the reproductive number (Rt) of the virus. Lower Rt numbers indicate low virus spread in the population.
A recent study co-authored by Dr. Rochelle Walensky, published in the Journal of health affairs, shows that a low efficacy vaccine (25%) administered to a population with low Rt numbers, is more successful in controlling the virus compared to a vaccine with much higher efficacy (75%) administered at the time when Rt numbers are higher in the population. The Rt numbers can be lowered by following social distancing, wearing masks and avoiding large social gatherings. The success of Covid-19 vaccine requires ongoing commitment of each one of us to follow these preventative measures.