Is it appropriate to use acronyms when citing a source in MLA? I'm writing an MLA research paper for a school assignment. When citing a source in-text, is it appropriate to use an acronym? For example, I'm citing the Centers for Disease Control and Prevention. Would it be acceptable to cite the source as (CDC)? If I'm citing the source at multiple points in the paper, could I cite it with the full name the first time and with the acronym for any subsequent citations?
From the 7th edition of the MLA handbook. 


  Abbreviations are used regularly in the list of works cited and in
  tables but rarely in the text of a research paper (except within
  parentheses). In choosing abbreviations, keep your audience in mind.
  While economy of space is important, clarity is more so. Spell out a
  term if the abbreviation may puzzle your readers.... The trend in 
  abbreviation is to use neither periods after letters nor spaces between 
  letters, especially for abbreviations made up of all capital letters.


The following points are from a MLA style guide on the doc scribe site.


If an acronym is commonly used as a word, it does not require explanation (IQ, LSD, FBI, ESP).
A term must be fully written the first time it is used, thereafter just the acronym is used.
If an acronym is not familiar use an expanded abbreviation; for MLA write Mod. Lang. Assn


Also from the same source (Page 8)


  The common practice in research writing to spell out the name or
  phrase to be abbreviated followed by the acronym in parentheses.
  Thereafter, just the acronym is used. For example, the Modern Language
  Association (MLA) publishes a journal. The reverse is also works—the
  MLA (Modern Language Association) publishes a journal.


So in your case Centers for Disease Control (CDC) or CDC (Centers for Disease Control) for your first citation and CDC afterwards should be fine.