  We prove that for any infinite-type orientable surface S there exists a
collection of essential curves {\Gamma} in S such that any homeomorphism that
preserves the isotopy classes of the elements of {\Gamma} is isotopic to the
identity. The collection {\Gamma} is countable and has infinite complement in
C(S), the curve complex of S. As a consequence we obtain that the natural
action of the extended mapping class group of S on C(S) is faithful.
