[Introduction of Bacillus sphaericus strain-2362 (GRISELESF) for biological control of malaria vectors in Guatemala]

Malaria continues to be an important health problem in a number of countries of Central and South America where it is considered as a highly prevent endemic disease. The objective of this paper is to assess the entomo-epidemiological impact of a pilot program for the biological control of malaria-transmitting vectors, which was implemented in 1998 in Escuintla, Republic of Guatemala. This program was based on the use of 20,000 L of biolarvicide Bacillus sphaericus- strain-2362 (GRISELESF) which was applied in the 46 localities of highest epidemiological risk at a rate of 10 mL/m2 of effective area of breeding. The entomologic effectiveness of this biolarvicide was monitored from the first 72 hours to 4 months after the application. There was a total larval reduction of 94.57 in the maturity stage of the water phase of Anopheles albimanus vector. The epidemiological analysis was carried out by comparing the rate of malaria prevalence (per 1000 pop) during 1997 and 1998. The five treated municipalities showed a statistically significant reduction of 50% (p 0.01). The results obtained in this paper coincided with those reported by comparable studies, so, this allowed us to recommend the use of the biolarvicide Bacillus sphaericus (strain-2362) as part of a comprehensive program of malaria-transmitting vector control in the Republic of Guatemala and other countries of the region.