Diagnóstico de enfermedades en colmenas de abejas africanizadas en Costa Rica: prevalencia y distribución de setiembre a noviembre del 2007

there are few reports concerning the occurrence of bee diseases in africanized honey bees (ahb) in costa rica. there are some preliminary studies, but the information is not entirely complete. for this reason, the aim of this study was to determine the prevalence of brood and adult bees diseases in ahb in costa rica. in our study, conducted between september and december 2007, 163 ahb colonies, belonging to 96 beekeepers from different geographic areas of costa rica, were randomly sampled. most brood and adult bees samples were taken from colonies located in san jose, guanacaste and alajuela. we found that 54.7%, 67.5% and 40.5% of the samples were positive to european foulbrood, nosema disease and varroosis, respectively. a low prevalence of tracheal mites (1.8%) and chalkbrood (4.4%) were found. all samples were negative to american foulbrood. the prevalence of european foulbrood was greater in october, whereas in september we found the lowest incidence. most of the samples positive to varroa (60.0%, n=61) showed a low mite infestation level, whereas 18.0% had a high level. november was the month with highest infection levels among cases of nosema disease (11.9% of the positive samples). these results are clear evidence of a high prevalence of european foulbrood, nosema disease and varroa mites in africanized bees in costa rica. this prevalence could be related to the time of the year for the sampling period and the scant disease-prevention programs in the apiaries. for these reasons, it is necessary to implement a health program, by means of regular samplings of the apiaries, to know the sanitary situation of the colonies and provide relevant recommendations for beekeepers