Health experts are expecting that, as temperatures cool and more people congregate indoors, Covid cases will again increase. Although it is believed that the mortality and general contagiousness will likely be lower, due to the vast majority of Americans having either been infected before or having had one or more of the vaccines, there is a danger of a new explosion of cases. One reason for this is that the BA.5 variant is extremely contagious, and overtook the previous BA.2 variant as the most prominent form of Covid earlier this summer. BA.5 is contagious enough that people are often getting infected again only months after having had it before, showing that it can evade prior immunities much faster than other variants have been able to. And of course any time a virus has a high mutation and contagion rate, the possibility for mutation to a new and potentially more deadly form increases.