The University gives you Sophos Anti-Virus for free, which you can download and install yourself via:
This will need to be reinstalled manually once a year due to licensing restrictions. This limitation can be overcome for fixed Departmental machines. Please get in touch with IT support who can install this special version for you.
Alternatively, Sophos give away a free (at time of writing) consumer version which is essentially the same and will always keep itself updated, barring a change to the operating system which leaves it "broken":
Either version of Sophos will display a shield icon in your Mac's menu bar. If this shield gains a cross in front of it, Sophos isn't updating. This could be due to no network connection but if you're connected and Sophos still can't update please get in touch with IT.