Prevalence of intestinal parasitic infections in Brazil: a systematic review

Abstract INTRODUCTION: Parasitic infections are considered a major public health problem due to their associated morbimortality and negative impact on physical and intellectual development, especially in the at-risk pediatric group. Periodic prophylactic administration of antiparasitic agents against soil-transmitted helminths is recommended by the World Health Organization (WHO) to control parasitic infections and disease burden. We aimed to evaluate the prevalence of intestinal parasitic infections in Brazil. METHODS: We performed a systematic review by searching the literature found in the PubMed, LILACS, and SciELO databases, followed by a meta-analysis of the proportions from studies published in English, Portuguese, and/or Spanish from January 2000 to May 2018. This systematic review was registered in the PROSPERO database (CRD42018096214). RESULTS: The prevalence of intestinal parasitic infections (protozoa and/or helminths) in Brazil was 46% (confidence interval: 39-54%), with 99% heterogeneity. Prevalence varied by region: 37%, 51%, 50%, 58%, and 41% in the Southeast, South, Northeast, North, and Central-West regions, respectively. Most studies (32/40) evaluated children (<18 years) and found an average prevalence of 51%. Children also had the highest prevalence in all four regions: Central-West (65%), South (65%), North (58%), Northeast (53%), and Southeast (37%). However, most studies evaluated specific populations, which may have created selection bias. Presumably, this review of intestinal parasitic diseases in Brazil includes the most studies and the largest population ever considered. CONCLUSIONS The prevalence of intestinal parasitic infections is high in Brazil, and anthelmintic drugs should be administered periodically as a prophylactic measure, as recommended by the WHO.

Acute diarrhoea in a community cohort of children who received an oral rotavirus vaccine in Northeast Brazil

Rotavirus is an important cause of childhood diarrhoea. A monovalent rotavirus vaccine (Rotarix®) was introduced into the Immunization Program of Brazil in 2006. In this study, we describe the incidence and burden of disease of rotavirus diarrhoea in two cohorts of children (vaccinated and unvaccinated). We followed two groups of 250 children under one year old, who were enrolled in December 2006 from a low-income residential area in Northeast Brazil. The children were monitored every two weeks for two years. Stool samples from children with diarrhoea were examined for the presence of rotavirus. Rotaviruses were genotyped using real time-polymerase chain reaction. The mean numbers of all-cause diarrhoea episodes/child (adjusted for age) in the first year were 0.87 and 0.84, in vaccinated and unvaccinated children, respectively. During the second year, the number of episodes/child decreased to 0.52 and 0.42. Only 16 (4.9 percent) of 330 stool samples were rotavirus-positive (10 vaccinated and 6 unvaccinated children) and only P[4]G2 rotaviruses were identified. All-cause diarrhoea episodes were more severe in unvaccinated children in the first year of age (p < 0.05), while vaccinated children had more severe episodes 18 months after vaccination. Rotavirus diarrhoea incidence was very low in both groups.