Some limited evidence supports sponging or bathing feverish children with tepid water.[59] The use of a fan or air conditioning may somewhat reduce the temperature and increase comfort. If the temperature reaches the extremely high level of hyperpyrexia, aggressive cooling is required (generally produced mechanically via conduction by applying numerous ice packs across most of the body or direct submersion in ice water).[2] In general, people are advised to keep adequately hydrated.[60] Whether increased fluid intake improves symptoms or shortens respiratory illnesses such as the common cold is not known.[61]