Welcome to the Voice of America’s News Words.
In the United States, COVID-19 cases are on the rise.
Breakthrough
Experts say the Delta variant is one reason. People who are not vaccinated against COVID-19 make up the most cases and deaths. Among fully vaccinated people, evidence shows a small minority getting breakthrough infections.
In medicine, a breakthrough infection happens when a virus breaks through the barrier a vaccine provides. The word breakthrough also means an important discovery that happens after a long time of trying to understand something.
*This article has been edited and reprinted from VOA Learning English with permission from Voice of America (VOA) for use in English language materials.
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