This simple and quick scripts allows you to remove comments with a special text on it. In this case, I used it to remove all comments in photos with the text "the_real_sims" on them, they were created by a virus of a couple of friends.

clean_fb_virus.py

# coding: utf-8

# To use this, you have to get a token from here: https://developers.facebook.com/tools/explorer/
# With publish_actions privileges (needed to be able to delete comments).

ACCESS_TOKEN = ""

# Main structure taken from:
# http://nbviewer.ipython.org/github/ptwobrussell/Mining-the-Social-Web-2nd-Edition/blob/master/ipynb/Chapter%202%20-%20Mining%20Facebook.ipynb

import requests
import json
import sys

base_url = 'https://graph.facebook.com/me'
fields = 'id,name,albums'

url = '%s?fields=%s&access_token=%s' %     (base_url, fields, ACCESS_TOKEN,)

# Interpret the response as JSON and convert back
# to Python data structures
content = requests.get(url).json()

if not "albums" in content:
    print content
    sys.exit(1)

# Code taken from:
# http://code.activestate.com/recipes/576602-safe-print/

def my_print(*args):
    """Safely print the given string.

    If you want to see the code points for unprintable characters then you
    can use `errors="xmlcharrefreplace"`.
    """

    errors = "replace"
    for u in args:
        s = u.encode(sys.stdout.encoding or "iso8859-1", errors)
        print(s),

    print ""

f = open("comments-deleted.txt","a")

albums = content["albums"]["data"]
for album in albums:
    print "-"*35
    print "Album:", album["name"]
    url = 'https://graph.facebook.com/%s/photos?&access_token=%s' %     (album["id"], ACCESS_TOKEN,)
    resp = requests.get(url).json()

    pictures = resp["data"]
    for p in pictures:
        if "comments" in p:
            comments = p["comments"]
            for comment in comments["data"]:
                msg = comment["message"]

                if "the_real_sims" in msg:
                    print "VIRUS DETECTED in picture", p["id"], "!"*40
                    print comment
                    f.write("%s\n" % comment)

                    delete_url = 'https://graph.facebook.com/%s?&access_token=%s' %  (comment["id"], ACCESS_TOKEN,)
                    delete_result = requests.delete(delete_url).json()
                    if delete_result is True:
                        print "Comment deleted successfully."
                    else:
                        print "Error, unable to delete comment", delete_result

f.close()