The best way to prevent sinusitis is to avoid colds and influenza and to treat them effectively when they do. To avoid colds and flu, people should always wash hands before eating, after going outside, and after possible exposure to infected persons.
Ordinary soap is sufficient.
New antibacterial soaps add little protection. Bacteria do not thrive on inanimate objects, such as subway poles or toilet seats, and of the organisms that do survive in such places, most are harmless. Residential and commercial hot tubs and whirlpool baths that are not properly functioning or cleaned, however, can become contaminated with organisms that are known to cause pneumonia. Everyone's diet should include foods such as fresh, dark-colored fruits and vegetables, which are rich in antioxidants and other important chemicals that help boost the immune system. There is no evidence that taking vitamins C and E in standard doses prevents colds, though they cause no harm.