When COVID-19 first emerged, scientists cautioned that developing an effective and safe vaccine could take longer than the commonly estimated figure of a year. The reason for the caution was that the previous quickest turnaround of a vaccine was for mumps in the 1960s, when development lasted four years. There were plenty of reasons to be cautious about the rapid development of a COVID-19 vaccine; a previous attempt to develop a vaccine against a different type of coronavirus actually increased cats’ risk of developing the disease.
