In the USA, the CDC (Centers for Disease Control and Prevention) compiles data on national vaccine uptake, but reporting can sometimes be delayed. The authors note that COVID-19 vaccine uptake was not the primary focus of any of the surveys. However, the bias in estimates of vaccine uptake in the two large surveys indicates that they are not representative of the US adult population. ‘Our study is the first to use a widely available benchmark – how many people have received the Covid-19 vaccine? Online surveys supply a plethora of data on everything from Covid-19 symptoms to in-person schooling to social distancing behaviour.
