What DEET concentration is recommended for protection against malaria when used with sunscreen?

• A. >20%
• B. <10%
• C. 5%
• D. 50%

Answer: (A)

When choosing a DEET repellent for malaria prevention, how long the protection lasts is the key factor. Higher DEET concentrations give longer-lasting protection, which is especially important in malaria-endemic areas where you’ll be outdoors and may be sweating or reapplying sunscreen. Because of that, a concentration greater than 20% is recommended for effective protection when sunscreen is used. This provides more hours of coverage than lower concentrations, reducing gaps in protection.

Low concentrations (well under 20%) wear off quickly and aren’t reliable for malaria protection in hot, sweaty conditions. A very high concentration like 50% isn’t necessary for most people and can increase the risk of skin irritation, especially with frequent reapplication or use on sensitive groups. For best practice, apply sunscreen first and allow it to absorb, then apply the DEET product on top, following label directions.