I live in louisiana. I get bit by mosquitoes wearing gloves, longpants, a
sweater, a scarf, a skimask, and goggles.
Unless you're armour is airtight, or has ventholes smaller than a mosquito,
than it offers you no protection from them.
If mobs can randomly see through the invis spell, then obviously mosquitoes
have see invis at 500%.
Zombies,ents,gargoyles etc should be immune. But that's looking too logical.

I live in finland, and in the worst summers there are so many
mosquitos the air is thickened by them. I can tell you, we have tried so
many ways to not be bitten 200 times in one day I'm starting to lose
hope. And I can tell you, if you are not totally covered in air-tight
suit, or a biohazard suit, they WILL find a way to bite you. Through
clothes, through repellants, through everything. If there is no way
to suck your blood through your clothes, they will find away underneath
them.

~/A

you get immune (well not immune, but lessen poison 75%) to musquito bites and
the stuff they put in you while sucking your blood, and after 1 months of
being bitten, you hardly notice them anymore. Then again next summer the first
bites are the worse again. So what im trying to say here, that the amount of
hps lost in mosquito bite should go down with every bite!?!?!?!?!

This place is reserved for something more intelligent.