The thing is, if the other team has a jungler, then you should be warding the gank spots (usually the tri bush, the river corner bush or dragon/baron area.
If you have those spots warded, (and mid lanes wards their side bushes, and is extra vigilant, then ganking by junglers should be easily prevented.
If you have a support character, running CV (Clarvoyance, a good skill to have on a Lux or Sona) on them is very helpful in finding out if a gank is coming, though another easy sign is if a side stops pushing the lane, i.e. only goes for last hits, and allows you to move up. Usually a big sign that they're going for a gank.
Jungler vs non just requires you to change your style, and once the mid phrase hits in, even if your team on a whole is down in kills, it's the team play that ends up deciding the end result. (Just don't feed their carries )
@Tensai
With GP's buff of late, he's become extremely strong in all area's of the game. A fed Gangplank is something to fear (especially with parlay + crit runes early game)
@Sir_NutS
Don't underestimate Sona's ability act like a carry. Her passive, plus a Sheen makes it far more damaging in team fights then people may realise. She's more of a carry/support hybrid then a pure support, as her heals are no where of the level of someone like Soraka, but she can deal more physical damage then people would realise, and is very good at harassing once she hits level 3 (and with her aura's it makes her laning partner that much more dangerous).