When I got the ADSL connection installed at home, the guy from my service provider didn't even bother to ask me if I knew about viruses, firewalls, spyware, etc.
From stats that I keep hearing from their installation, service, call center folks they must be averaging at least 2500 installations per month. Assuming that even half of these are of 24X7 type (or my 10-8 unlimited download) type, it could pose a serious problem if none of the users had a clue on security.
God save internet penetration in India. User awareness on such matters, especially down here is pretty low.
Note that the situation applies even to dialup lines, but then more so to DSL and such tecnology because of the amount of time spent online giving a chance for someone to try and attack the system.
Take care and use some kind of anti-virus, firewall, anti-spyware on your system.
My post here contains a few options and notes on useful tools.