DEET is often sold and used in spray or lotion in concentrations up to 100%. "Consumer Reports" found a direct correlation between DEET concentration and hours of protection against insect bites. 100% DEET was found to offer up to 12 hours of protection while several lower concentration DEET formulations (20–34%) offered 3–6 hours of protection. Other research has corroborated the effectiveness of DEET. The Centers for Disease Control and Prevention recommends 30–50% DEET to prevent the spread of pathogens carried by insects.