Hi all,
Thanks for your help. My first thought before posting was that it was a typo for Coombs, but now I think Joseph is on the right track, since the rest of the article mentions anti-tuberculosis meds several times. I also found this:
¿Que es el COMBE dentro del Historial Clínico?
http://mx.answers.yahoo.com/question/index?qid=2008101513091...
Of course the question remains of what to call it in English. This article seems to just say "Contacts of Persons with Infectious Tuberculosis".
http://www.cdc.gov/mmwr/pdf/rr/rr5415.pdf