There isn't a vaccine for either SARS or MERS, in part because they don't happen very often. In the case of SARS, that one outbreak was it so far, while in MERS

There isn't a vaccine for either SARS or MERS, in part because they don't happen very often. In the case of SARS, that one outbreak was it so far, while in MERS we've seen a grand total of about 1500 people infected worldwide, although the disease is still circulating.