On Thursday, police arrested a pharmacist at a hospital in Wisconsin, US, on suspicion of sabotaging more than 500 doses of a coronavirus vaccine.

When the misplaced vials were found, the pharmacist said that it was an unintentional error. However, later he admitted to removing the vaccine from cold storage in order to spoil it. Some of the doses were given to people before hospital officials determined that the medication had been left unrefrigerated for long enough to become ineffective. The medication was made by the company Moderna, and the remaining doses had to be thrown away.

Moderna assured the hospital that those doses that were injected posed no safety issue to people. The pharmacist didn¢¥t tamper with the vaccine in any other way other than removing it from refrigeration.

Difficult words: sabotage (to deliberately destroy or damage), vial (a small glass container that is used for holding liquid medicines), tamper (to secretly make changes in something).