Is travel insurance available for multiple trips?
Of course yes as long as they are trips and among the warrantee period, actually, you can go to consult a layer or you can consult the insurance company when you buy the insurance. Ask them carefully in case they are playing cheats, http://www.raybanspanishsitio.com/tipos-de-modelos-ray-ban-3183-c-1_76.html
Make sure which countries cover your insurance, and make sure you can contact them for any questions everywhere just via internet.
I used a travel insurance which cover any countries for a certain period of time but certain specific countries (U.S.A. for example because of a different medical system)