RESUMEN
185 children 1 to 14 years old living in the suburb of San Rafael (Zulia State, Venezuela) were selected for this study with the following results: Eggs of Ascaris lumbricoides in the stool samples before administration of a drug to the children and the worms recovered after drug, induced expulsion, showed a high aggregation (K = 0.115 and K = 0.122, respectively); the aggregation of the recovered worms was more intense in girls (K = 0.083), than in boys (K = 0.220); among the blood groups, A. lumbricoides resulted highly prevalent (100 percent) and less overdispersed in group AB (K = 1.26; n = 5), while in the other blood groups the spatial aggregation pattern was strongly overdispersed (A = 0.159; B = 0.133 and O = 0.210); individuals of the blood group rBr, make the greatest contribution to environmental contamination, because they presented the greatest values for the abundance and a more intense overdispersion