Q: ipad need antivirus?

There are no viruses for iOS, there are no virus protection apps for iOS, and so no, you don't need one.

No need antivirus.

Viruses are the least of your concern in iOS.. There were many Security Measures added into iOS over the past few years and thanks to these measures, iOS is safe from Hacks. To understand this, i will introduce you to a Well-known Security Feature in iOS which is "SandBoxing". SandBoxing is the method of placing an App in a secured environment, seperating the Application from the Core of the System. Let's say, you've downloaded a game in the App Store, once you've opened that app, iOS automatically places that app into an environment where it can't fiddle or do anything into the Core of iOS the system itself. As far as i know though, there are second to none viruses for iOS. Don't worry, You're safe with iOS.

The biggest concern you have with the device is your own behavior. Even though there is no known virus for iOS devices, if you click on the wrong link and enter your info in the wrong place, you'll be just as vulnerable to identity theft  on an iDevice as you will on any other device.

Your reply (and those of many others) concerning viruses usually address those which may be embedded in apps.  And because Apple apps must be "virus free," you (and others) say that there is no need for a virus screening app.  Well, how about viruses which infect a device though an Email???  Being a former PC user and having worked for a government department which was continually under cyber attack, I am crazy paranoid about malware. Could you please address my concerns?

the vast majority of viruses are .exe files, which do not run on iPads since .exe runs on PC's.  

For those that are written for macs, well the iPad doesn't use the same operating system as a mac, so they won't run either.

Also, the ipad is 'sandboxed', meaning that it lacks a file manager which is what viruses use to spread and information is shared between apps usually with the    assistance/direction of a person.

Is an ipad totally immune?, is anything totally immune? I'm sure there are people out there trying to crack their way in and be the first to infect an ipad, but as of right now there is no known virus (a virus being a malicious program that propogates itself across the operating system) for non-jailbroken devices.

There are apps that will scan your email for to remove viruses designed for other PC & mobile device OSes so that you don't accidentally forward a virus to a recipient.  Virex, which is an OS X AV app, has an iOS app for this, most other paid & possibly free AV apps for OS X offer these in the App Store.  Because iOS is sandboxed, apps cannot use code from another app nor access another apps content.  Many iOS services like Bluetooth & data from the built-in calendar & contacts require an app to request access from the user on its first run.  As previously mentioned, social engineering / phishing scams are the weak link on any smartphone or computer, because it relies on the user, not the installed code, to provide the info, like addresses, social security, account numbers, etc.  Even though Apple thoroughly reviews each app before it can be posted to the App Store, there was an article where a security expert was able to post a malicious app to the App Store, passing the app approval process and available for public downloading.  It wasn't really that hard, because it used a restriction on apps which can only be voluntarily enforced by the developer, a "promise not to...".  Apple has no way restrict app behavior in this way via iOS controls nor AV apps

Currently there's no known virus affecting iPad as long as you don't Jailbreak your iPad.

http://support.apple.com/kb/HT3743