Add a little vanilla extract in water and you've got a safe, natural mosquito repellent for people and horses.
An old country formula to ward off gnats and mosquitoes is to mix a tablespoon of vanilla extract into a cup of water to create a safe, natural mosquito repellent. I rubbed this on my children's faces and it worked so well I tried the solution on my horse's ears and eyes. It worked like a charm.
(Country Lore, August 1987)