Although vaccination is carried out worldwide, the vaccination rate varies greatly. As of 24 May 2021, in some countries, the proportion of the population fully vaccinated against COVID-19 has exceeded 50%, but in many countries, this proportion is still very low, less than 1%. This article aims to explore the impact of vaccination on the spread of the COVID-19 pandemic. As the herd immunity of almost all countries in the world has not been reached, several countries were selected as sample cases by employing the following criteria: more than 60 vaccine doses per 100 people and a population of more than one million people. In the end, a total of eight countries/regions were selected, including Israel, the UAE, Chile, the United Kingdom, the United States, Hungary, and Qatar. The results find that vaccination has a major impact on reducing infection rates in all countries. However, the infection rate after vaccination showed two trends. One is an inverted U-shaped trend, and the other is an L-shaped trend. For those countries with an inverted U-shaped trend, the infection rate begins to decline when the vaccination rate reaches 1.46–50.91 doses per 100 people.
【저자키워드】 COVID-19, pandemic, herd immunity, infection rate, vaccination rate, turning point, 【초록키워드】 vaccination, Immunity, COVID-19 pandemic, vaccine dose, Spread, United Kingdom, dose, Hungary, The United States, country, selected, carried, proportion, eight, less, reducing, reached, exceeded, vaccinated against COVID-19, 【제목키워드】 Herd, Effect, Rate,