This is the first study to describe the spatial distribution of acute diarrhea and enteric infections in a cohort of infants living in a low income community in Brazil with high population coverage of rotavirus vaccination. The number of acute diarrhea episodes/child/year was low and very few children had rotavirus diarrhea detected. These findings are similar to the ones found by Vieira et al. (2011) , that in an urban district of Aracaju city detected 0.87/episodes/child/year and 3.0% rotavirus associated diarrhea.
One of the particularities of this study was the occurrence of rotavirus in 2.5% of the stool samples without diarrhea, contrary to the findings of Borges et al. (2011)  that found no rotavirus among non-diarrhea stool samples. This finding suggests that the attenuating effect of the vaccine may be responsible for the subsequent asymptomatic infections, which is similar to original data from Mexico, where the natural rotavirus infection was partially protective against subsequent infection .
We observed a fluctuation on A. lumbricoides infection, but in the last period there was on increase (6,8%) in agreement with Roy et al.  in Bangladesh. The increasing prevalence of intestinal parasites by age observed in children is related to the process of child development (mobility and interaction with the environment) and longer exposure to environmental conditions . During the 12 months of follow-up, 32 (25%) children may have been reinfected by parasites (protozoa or helminths), with 15 (47%) by A.lumbricoides more than once. During the 12 months of follow-up, 32 (25%) children may have been reinfected by parasites (protozoa or helminths), with 15 (47%) by A.lumbricoides more than once. We have not reassessed the children after treatment, but we have stressed to the families the importance for parasitic treatment and checked drug use.
Within protozoa, E. nana and G.lamblia were more prevalent and detected in earlier ages (4-13 months). E. nana is a commensal microorganism and it´s detection may indicate greater environmental contamination and other infestations may be found [25, 26].
In our study, enteroparasites were also detected in diarrheic samples, similar to the findings from Nigeria, where 18.6% of toddlers with diarrhea were infected  and in Bangladesh, where 11.6% of infants had enteroparasites .
Most families in Laranjeiras, both in rural and urban areas, had water supplied by the public water system that used to work with constant discontinuity. Consequently, there was frequent storage of household water, most often improperly, compromising the quality of the water used by these families. The sanitary disposal ways, including the sewage, dumping of human waste and wastewater in public streams, were also poor. The homogeneity and frequency of these inadequate characteristics in the study area contributed to the significant occurrence of intestinal parasites, even in early childhood. Other studies have observed that such conditions are determinant to increase parasitic intestinal infections in different places [7, 3, 28].
The occurrences of parasites, rotavirus and diarrheal episodes in infants in this study have irregular distribution within the geographic space of Laranjeiras. The estimation of case intensity in the different areas by the Kernel method revealed higher frequency of enteric infections in the urban area and surrounding regions, where there is higher concentration of households and therefore a greater number of people living in an environment with poor sanitation.
One of the limitations of this study was the method of collection of stool samples, which depended on the availability of those responsible for the children in delivering monthly those samples, which may have contributed to an underestimation of the number of episodes of diarrhea. However, the children were visited at home at least every two weeks, which may have minimized the underestimation. Diarrhea episodes were not severe, and mothers may have not considered its occurrence as a problem and did not collect a sample.