I agree with Logan and Blip. You can omit the additional articles in American English. From the standpoint of formal writing, it might be seen as being better to include them though.
Using Logan's sentence pattern, there is also this example:
For breakfast, I had a bagel, muffin, slice of cheesecake, and fruit.
which is the same as
For breakfast, I had a bagel, a muffin, a slice of cheesecake, and fruit.
Note that fruit means fruit in general here though. It could a banana and an apple, or whatever. It isn't specified and you shouldn't really put "a fruit" when you are speaking about fruit in general because it is a mass noun. :)