Why Choosing the Right Repellent is Crucial in the Caribbean
In the Caribbean, mosquitoes are not just a nuisance: they are vectors of serious diseases such as dengue, chikungunya, Zika, and malaria. An effective repellent is your first line of defense. But not all products are equal, and the market is full of options with widely varying efficacy.
This guide helps you understand the different active molecules, their advantages and limitations, to make an informed choice suited to your situation.
Active Molecules: A Comparison
DEET (N,N-diethyl-meta-toluamide)
DEET is the global reference for skin repellents. Approved by the WHO and the US CDC, it is effective against a wide range of biting insects, including Aedes and Anopheles mosquitoes.
Recommended concentrations:
- 10–30%: 2 to 6 hours of protection, suitable for adults and children over 2 years
- 30–50%: 6 to 12 hours of protection, recommended for high-risk areas like the Caribbean
- > 50%: no additional proven benefit, increased risk of skin irritation
Precautions: avoid contact with eyes, mucous membranes, and wounds. Do not apply to young children's hands. Not recommended for infants under 2 months.
Icaridin (or Picaridin)
Icaridin is a modern alternative to DEET, with comparable efficacy but better skin tolerance. It is odorless, non-greasy, and does not damage plastic or synthetic materials (unlike DEET).
Recommended concentrations:
- 20%: 8 to 12 hours of protection against mosquitoes
- Usable from 2 years of age
Icaridin is particularly recommended for sensitive skin and children.
IR3535 (Ethyl 3-[N-butyl-N-acetyl]-aminopropionate)
Developed by Merck, IR3535 is a molecule of natural origin (amino acid analogue). Its efficacy is slightly lower than DEET and icaridin, but it has an excellent safety profile.
Recommended concentrations:
- 20–35%: 4 to 8 hours of protection
- Usable from 6 months of age
Essential Oils: Beware of Common Misconceptions
Essential oils of citronella, lemon eucalyptus, or geranium are often presented as natural alternatives. While they do have a real repellent effect, their duration of action is very short (30 minutes to 2 hours maximum) and their efficacy is insufficient in areas with high disease transmission risk.
Recommendation: essential oils can complement protection, but should not replace an approved chemical repellent in endemic regions.
How to Apply Repellent Correctly
The efficacy of a repellent depends as much on its formulation as on how it is applied:
- 1Apply to all exposed areas: arms, legs, neck, ears — avoiding eyes, mouth, and wounds
- 2Do not apply under clothing: the repellent must be in contact with air to be effective
- 3Reapply according to the indicated protection duration, and after swimming or heavy sweating
- 4Apply sunscreen first, then repellent on top (not the other way around)
- 5Wash treated areas with soap after coming indoors
Repellents for Children and Pregnant Women
Children
- Under 2 months: no chemical repellent — use mosquito nets only
- 2 months to 2 years: IR3535 at 20% or icaridin at 10%
- 2 to 12 years: DEET at 10–30%, icaridin at 20%, or IR3535 at 20–35%
- Over 12 years: same recommendations as adults
Pregnant and Breastfeeding Women
Icaridin and IR3535 are preferred over DEET during pregnancy, although DEET remains usable at concentrations ≤ 30%. Consult your doctor before any travel to endemic areas.
Permethrin Treatment for Clothing
In addition to skin repellents, treating clothing with permethrin provides significant additional protection. Permethrin is a contact insecticide that kills or repels mosquitoes upon contact with treated fabric.
It can be applied as a spray to clothing, mosquito nets, and even tents. The effect persists after several washes. It is safe for humans once dry, but toxic to cats — use with caution if traveling with a feline companion.
Summary Table
| Molecule | Efficacy | Duration | Minimum Age | Skin Tolerance |
|---|---|---|---|---|
| DEET 30–50% | Excellent | 6–12 h | 2 years | Moderate |
| Icaridin 20% | Excellent | 8–12 h | 2 years | Very good |
| IR3535 20–35% | Good | 4–8 h | 6 months | Excellent |
| Essential oils | Low | < 2 h | Variable | Variable |
Conclusion
For a Caribbean trip, prioritize icaridin at 20% or DEET at 30–50%. These two molecules offer the best protection against disease-carrying mosquitoes. Combine them with covering clothing treated with permethrin and mosquito nets for optimal protection.