A little preview of my article 'how to get rid of termites'! read the full article here! http://howtoridof.com/how-to-get-rid-of-termites-yourself/

quick answer to the question:

termites tend to spread pretty fast so you need to get rid of them as quickly as possible.

The quickest way I think to get rid of termites is to place a wood slab inject with toxins at the infested areas.

Take note that's it's possible that these termites come back again, so it's advisable you take a look at prevention solutions. One thing I can say is that plants and trees can help the termites in entering your house, so ensure that they are well distanced.