In this context it's not 'a vacation' but 'days off' or 'vacation days'.
edit: Actually 'le vacanze' is used quite a lot for 'the vacation' as in this sentence. However vacanze can also be 'days off' or 'holidays' as in 'Quante vacanze hai?'. So I think that's what is behind the use of the plural.
If the translation refers to vacation days why isn't the plural "are" used?
in this case what we refer to as singular in English is referred to as a plural in italian and vice versa
ischweagle, because in the translation it is not a plural. (and in Italian they do use the verb in plural)
It is because the Italian names for the months are different to the English ones (assuming you meant to say novembre not november)