If you take a course of Vitamin B tablets, mosquitoes will not bite you, they cannot stand the scent/taste caused by Vitamin B, which by the way is undetectable to humans. The Vitamin B course takes about 10 days to be effective, and must be maintained daily to retain its full effect.
You need to really dose up on the Vitamin B for best protection from mosquitoes, and while your body will eliminate excess doses, check with your doctor or pharmacist about safe limits, particularly if you have other health problems or are on medication.
Mosquitoes are most active at dawn and dusk, so avoiding being outdoors at these times will reduce your exposure dramatically, and wear close weave loose fitting clothing with long sleeves and legs.
Use DEET based repellant on exposed areas like hands and face, and around ankles if not wearing high boots.
There are specialist suits available if you have to be out in mosquito infested swamps or jungles, but they are hot and uncomfortable, and definitely are NOT a fashion statement.
