It might be built on the DNA of the successful Flash and iOS Pandemic series, but Plague Inc. has mutated into the slickest simulation of humanity’s destruction on the App Store (and soon on Google Play.)

If you can put aside your moral qualms about killing billions with a virus that makes smallpox look like a touch of the sniffles, then you’ll find Nndemic Creations’s game to be one of the most engrossing strategy titles around.

Perfect pestilence

It’s not just nasty viruses that you get to unleash upon the world - you can pick from hideous contagions ranging from humble bacteria to a smart nano-virus, with a "built in kill switch” – although they need to be unlocked or bought via in-app purchases.

Once you’ve picked your biological poison you’re taken to a bustling map of the world. Life, represented by planes and boats zipping across the screen, will continue as normal until you pick a country to infect first.

People will soon to start to fall ill, but symptoms will be minor until you begin to add new features paid for with DNA points acquired whenever the disease spreads.

Each augmentation or mutation can increase the severity of symptoms and infection rates, help the illness spread through different animals, or protect it from government-made cures and inhospitable climates.

Meanwhile, a ticker tape news reader at the top of the screen highlights how the world is responding to your plague, along with some chortle-worthy satirical gags and some natural events to exploit – like a sudden bird migration your plague can hop aboard.

Panic in the streets

Although you’ll spend a lot of time jumping between menus, Plague Inc.'s tap controls and distinctive icons for each option make it a straightforward, ultra-intuitive experience.

Such streamlined design leaves you plenty of time to work on a winning strategy, with the main choice being whether to hit the population hard with a deadly, highly contagious disease or let a subtle virus spread globally before suddenly unleashing fatal symptoms.

And even with the first DLC released this month (centred around an infectious brain worm and boasting new gameplay features, like Trojan Planes you can aim at uninfected countries), the three difficulty modes, unpredictable AI, and endless virus combinations mean Plague Inc. offers stacks of replayability.

Admittedly, the immoral concept of trying to wipe out all life on earth – no matter how imaginatively it’s presented – won’t appeal to many good-natured gamers.

Those looking for a smart, deliciously demented antidote to traditional strategy gaming, however, will want it to contract this infectiously entertaining title immediately.