Mosquito-borne disease threat and DEET repellent guidance

Mosquitoes transmit around 78 diseases, causing up to one million deaths each year, including about 600,000 from malaria. In Cuba, economic hardship and weakened public‑health services have worsened control efforts, allowing a dengue and chikungunya epidemic that began in 2025. The Pan American Health Organization reported 1,457 cases in February and a total of 67 deaths, highlighting the ongoing risk.

The chemical repellent DEET, discovered during World War II and patented in 1946, remains the world’s most widely used, effective and inexpensive mosquito deterrent. Scientists continue to endorse it as the reference standard for personal protection.

Mosquitoes bite only fertilized females, locating hosts by detecting carbon‑dioxide, body heat, visual cues and a complex mix of skin‑borne chemicals. Individual attractiveness varies with genetics, skin microbiota and compounds such as lactic acid, with studies suggesting up to 85 % of the attraction may be hereditary.