Is your host is capable to fight with spams? Then your answer is very important actually Website hosting companies generally provide their clients email accounts for use with their domain, but are you with a host that provides those email accounts with Spam and virus protection?
Webmasters shouldn't need to seek out local filters for their site's contact email addresses. There are a variety of server level solutions a hosting company can offer to protect their users from unwanted emails. A most basic step is provision of a very rudimentary blacklist functionality to their users, allowing them to prevent future Spam emails from arriving from the same address.
More advanced server level Spam filters are available. A small advance is accomplished using keyword filters. Keyword filters merely check for instances of a certain string of characters and deny the message if that string if found.
Currently the most sophisticated filtering methods use Bayesian inferences. Bayesian filters take a large data set and determine the probability a message is Spam based on its similarity to previous Spam messages.