Respuesta :
One of the biggest concerns in doctors that I have seen from watching TV is that flu pandemics if left untreated can turn deadly not within a matter of days but within a matter of minutes. Hope this helped.
Mutation on the virus, once mutated vaccinations are no longer effective. More people who get vaccinated the less likely there is a chance of virus mutation. This is called herd immunity.
Can spread very quickly and sometimes the method of transportation is difficult to pinpoint, therefore more difficult to contain.
Can spread very quickly and sometimes the method of transportation is difficult to pinpoint, therefore more difficult to contain.