Study summary
Efficacy of Unregulated Minimum Risk Products to Kill and Repel Ticks
Eisen L (CDC)
- Study type
- Review
- Year
- 2024
- Published in
- Emerging Infectious Diseases 30(1)
- Evidence strength
- Definitive evidence
Summary
Authoritative CDC review synthesizing human-skin complete-protection-time data for botanical (25(b) minimum-risk) tick repellents against Ixodes scapularis, with DEET as the benchmark.
Key findings
Human-skin tick CPT bands: cinnamon oil, clove oil, and geraniol each ~1-2 h; cedarwood, citronella, cornmint, garlic, geranium, lemongrass, peppermint, spearmint and thyme each under 1 h; DEET more than 6 h. No 25(b) active exceeded 2 h. Confirms minimum-risk products undergo no EPA efficacy review.
Limitations
Review aggregating heterogeneous primary sources with large product-to-product variability; notes that published skin-bioassay data on many finished 25(b) tick products are entirely lacking.