The larvicidal activity of brown algae Padina minor (Yamada 1925) and Dicyota linearis (Greville 1830) against the dengue vector, Aedes aegypti (Linn 1762) (Diptera: Culicidae).

challenging global public health, ranging from self-limiting dengue fever to more severe life-threatening form termed as dengue hemorrhagic fever. In the last 50 yr, its worldwide incidence increased by 30 fold and it was estimated that 1/3 to 1/2 of the world’s population is at risk of becoming infected. Currently, epidemic dengue hemorrhagic fever is a leading cause of hospitalization and death among children in Southeast Asia. Worldwide, out of 50 million infections estimated by the World Health Organization (WHO) each year, 500,000 cases are dengue hemorrhagic fever and 22,000 deaths were mostly children1. In the Philippines, the Department of Health (DOH) surveillance report data in 2011 showed that there were 70,204 dengue cases mostly from 1–10 yr age groups and with 396 deaths. It is already a common knowledge that Aedes aegypti (Diptera: Culicidae) is the vector of dengue hemorrhagic fever and is endemic in Southeast Asia, Pacific Islands, Africa and America. Because dengue virus is transmitted to human by the bite of infected Aedes mosquito, endemicity or hyper-endemicity of dengue virus requires existence of sufficient vectors2. The recrudescence of dengue hemorrhagic fever is due to the high number of breeding places and increasing resistance to insecticides3. In developing and underdeveloped countries, the habit of adding water to containers for drinking, cooking or bathing, water storage for ornamentation trigger dengue outbreaks even during the dry season2. The use of synthetic chemicals to kill the vector mosquito is not so effective because it is highly domesticated and many adults are found indoors3. So far, no available vaccine for dengue has been made or discovered. The only successful way to reduce mosquito densities is attacking the larval breeding places through sanitation activities. The marine algae are rich sources of biologically active metabolites. These active metabolites are synthesized J Vector Borne Dis 50, March 2013, pp. 68–70