Pedialyte. Oral electrolyte fluids, like pedialyte, will replenish not only the liquids lost though vomiting, but also the electrolytes. The key to success is small amounts frequently-give 1-2 tsp every ten minutes for one hour, if no vomiting, increase to 3 tsp every ten minutes, advancing as tolerated.
Think straw. Great question. Drinking fluids does indeed help to reduce fever. Liquids that are cold are fun to drink. Drinking slowly thru a straw seem to allow the intake at a rate that lessens the chance for too much to be consumed and then we throw up. Remember it is not a high fever we are concerned about. Fever indicates an infection. Reducing fever makes us feel better and thus able to drink more.