Water-contact patterns and schistosoma mansoni infection in a rural community in northeast Brazil

We evaluated the influence of water-related human activities, contaminative behaviour, house location, education and socio-economic status on endemic Schistosoma mansoni infection. The study was conducted in a hilry non-irrigated area of rural northeast Brazil amongst a defined population of subsistence farmers, of whom 93% were infected by age 20. The area was mapped, water bodies were surveyed, and a detailed questionnaire was performed on each household. Infection was assessed by duplicate stool examinations using the sensitive Bell technique to quantify egg excretion. For each household, and index of intensity of infection was computed by grouping individual log-transformed egg counts as an age-sex adjusted Z score. Few households had a sanitary installation or a domestic water supply. However, neither water-contact nor contaminative behavior were indiscriminate. The people made considerable effort to defaecate far from a water source, to obtain household drinking water from the cleanest source, and to bathe only at certain sites where privacy is assured. Land ownership and literacy correlated poorly with the household index of intensity of infection. The key influence on infection status was the relative location of the house and snail-free or snail colonized water sources. In this area, a safe domestic water supply is the critical input needed to achieve definitive control of endemic Schistosomiasis.

Five cases of nosocomial and community-acquired legionnaires' disease in São Paulo, Brazil

Legionella sp has been emerging over the last decade as an important cause of pneumonia both hospital and community-acquired. Following an outbreak in a Renal - Transplant Unit stocked serum was tested for antibodies against Legionella pneumophila serogroup 1, and 5 cases of Legionnaires' Disease were reviewed. Two of the cases were nosocomial and three cases were community - acquired. Clinical and laboratorial aspects were similar to those expected for other causes of pneumonia, however jaundice was encountered in two cases. This study suggests that the real incidence of pneumonia caused by Legionella sp is being underestimated and the authors emphasize the importance of considering Legionnaires' Disease when empirically treating community - acquired pneumonia

Etiology and severity of community acquired pneumonia in children from Uruguay: a 4-year study

The 4-year study (1987-1990) covered the major clinical-epidemiological characteristics of pneumonia in children as diagnosed at the emergency service of the Children's Hospital, as well as etiologies, and factors involved in the most severe cases. Etiology was determined in 47.7% of the 541 pneumonia cases, involving 283 pathogens of which 38.6% were viruses and 12.6% bacteria. Viral and mixed etiologies were more frequent in children under 12 months of age. Bacteria predominated in ages between 6 and 23 months. Among the viruses, respiratory syncytial virus predominated (66%). The bacterial pneumonias accounted for 12.2% of the recognized etiologies. The most important bacterial agents were S. pneumoniae (64%) and H. influenzae (19%). H. influenzae and mixed infections had a relevant participation during the 1988 season, pointing to annual variations in the relative participation of pathogens and its possible implication in severity of diseases. Correlation of severity and increased percentage of etiological diagnosis was assessed: patients with respiratory rates over 70 rpm, or pleural effusion and/or extensive pulmonary parenchyma compromise yielded higher positive laboratory results. Various individual and family risk factors were recognized when comparing pneumonia children with healthy controls.

Frequency of serum anti-cysticercus antibodies in the population of a rural Brazilian community (Cássia dos Coqueiros, SP) determined by ELISA and immunoblotting using Taenia crassiceps antigens

Considering the impact of cysticercosis on public health, especially the neurologic form of the disease, neurocysticercosis (NC), we studied the frequency of positivity of anti-Taenia solium cysticercus antibodies in serum samples from 1,863 inhabitants of Cássia dos Coqueiros, SP, a municipal district located 80 km from Ribeirão Preto, an area considered endemic for cysticercosis. The 1,863 samples were tested by enzyme linked immunosorbent assay (ELISA) using an antigenic extract from Taenia crassiceps vesicular fluid (Tcra). The reactive and inconclusive ELISA samples were tested by immunoblotting. Of the 459 samples submitted to immunoblotting, 40 were strongly immunoreactive to the immunodominant 18 and 14 kD peptides. Considering the use of immunoblotting as confirmatory due to its high specificity, the anti-cysticercus serum prevalence in this population was 2.1%.

Chagas disease in a community in Southeast Brazil: I. A serlogic follow-up study on a vectorcontrolled area

The prevalence of Trypanosoma cruzi infection was evaluated in Berilo, Minas Gerais (MG), Brazil, from January to July 1997. A serological survey using the indirect immunofluorescence test (IFT) in dried blood collected on filter-paper was performed in a sample of 2,261 individuals. The overall prevalence rate of T. cruzi infection was 18%, and reached 50% in individuals older than 30 years from rural areas. The percentage of seropositivity was 0.17% among individuals younger than 10 years old, suggesting that vectorial transmission is controlled in the area. A decrease in prevalence rates among people born after 1960 and 1970 was observed and this appears to be correlated with the beginning of control programs. A reduction in T. cruzi infection rates was observed when comparing our results with the rates estimated in a serologic study carried out in Berilo in 1983(11).

Impact of antihelminthic treatment on infection by Ascaris lumbricoides, Trichuris trichiura and hookworms in Covas, a rural community of Pernambuco, Brazil

This work aims to evaluate the impact of drug treatment on infection by Ascaris lumbricoides (Al), Trichuris trichiura (Tt) and hookworms (Hook) in a rural community from the sugar-cane zone of Pernambuco, Brazil. Four parasitological surveys were carried out from March 2001 to March 2002. Individual diagnosis was based on eight slides (four by the Kato-Katz method and four by the Hoffman method) per survey. Infected subjects were assigned to two groups for treatment with either albendazole (n = 62) or mebendazole (n = 57). Prevalence of infection fell significantly (p < 0.05) one month after treatment: Al (from 47.7% to 6.6%); Tt (from 45.7% to 31.8%) and Hook (from 47.7% to 24.5%). One year after treatment, infections by Tt and Hook remained significantly below pre-control levels. A substantial decrease in single-infection cases and multiple infections was found. Egg-negative rate was significant for Al (94.0%), Hook (68.3%) but not for Tt (45.5%), and did not differ significantly between subjects treated with mebendazole or albendazole. Egg counts fell significantly in the individuals remaining positive for Tt. It is recommended that antihelminthic treatment should be selective and given at yearly intervals preferably with albendazole, due to its cost-effectiveness.

Study of enteroparasites infection frequency and chemotherapeutic agents used in pediatric patients in a community living in Porto Alegre, RS, Brazil

Parasitic infections caused by intestinal protozoan and helminths affect more than two billion people worldwide and chemotherapy is the most commonly used therapeutic procedure. Considering the problems created by parasitic infections and the incorrect use of drugs, the aim of this work was to detect the frequency of enteroparasites infection and to estimate the use of chemotherapeutic agents in children living in the periphery of the city of Porto Alegre, RS, Brazil. Ninety-six preschool age children, who had parasitological exams and who used antiparasitic drugs, were analyzed. The efficacy of treatment was evaluated by stool examination repeated six months after treatment. The same diagnostic test was used to evaluate parasitological cure, which was defined as absence of eggs and cysts in the stool. From these children, 79 (82.3%) were contaminated by some species of parasite, the most prevalent were Ascaris lumbricoides, Trichuris trichiura and Giardia lamblia. The most commonly used drugs were mebendazole (86% of prescriptions) and metronidazole (30.3%). The cure rate in the 79 children, examined 6 months after treatment, was 65.3% for A. lumbricoides and 66.1% for T. trichiura. This study suggests that a continuous education program regarding the prevention and treatment of parasitic infections is an essential tool for their eradication.

Blastocystis hominis and other intestinal parasites in a community of Pitanga City, Paraná State, Brazil

The objective was to estimate the prevalence of Blastocystis hominis, to evaluate the effectiveness of different techniques for its diagnosis as well as to estimate the prevalence of other intestinal parasites in the community of Campo Verde, a district of Pitanga. The work was carried out from August to October 2004. Samples of feces from children and adults were collected and submitted to the techniques of direct wet mount, flotation in zinc sulphate solution, tube sedimentation, sedimentation in formalin-ether and staining by Kinyoun and iron hematoxylin methods. From 181 studied individuals, 128 (70.7%) showed protozoa and/or helminths in stool samples. The most prevalent species were Endolimax nana (33.7%); B. hominis (26.5%); Giardia lamblia (18.2%); Entamoeba coli (17.1%); Ascaris lumbricoides (16.6%); Iodamoeba bütschlii (9.4%); and ancylostomatidae (7.7%). B. hominis was only identified by the techniques of direct wet mount, sedimentation in formalin-ether and staining by iron hematoxylin, though the latter was less sensitive than the other methods. The high frequency of B. hominis demonstrated by this study indicates the need to include laboratory techniques that enable identification of the parasite on a routine basis.

Seroprevalence of toxoplasmosis in a low-income community in the São Paulo municipality, SP, Brazil

Toxoplasmosis is one of the most common zoonoses worldwide. The seroprevalence for T. gondii in human population from Brazil might range from 40 to 80%. The aim of this paper was to study the seroprevalence of T. gondii infection in children from age one to 15 living in a low socioeconomic community, named community of Jardim São Remo in the year of 2002. The community is located in the West area of São Paulo municipality, São Paulo State, Brazil. Antibodies to T. gondii were found in 110 (32.4%, CI 95%: 27.5 - 37.7) of the 339 children tested with indirect immunofluorescent antibody test. The titration of the samples revealed 29 children with serum titer equal to 16, 14 children with 32, 18 children with 64, 21 children with 128, 20 children with 256 and eight children with serum titer > 512. The age dependence of the prevalence of T. gondii infection and the association between seroprevalence for T. gondii and seroprevalence for T. canis suggest that the infection is chiefly postnatal. Seroconversion in infant population of community Jardim São Remo occurs in children as young as two years old, earlier than in the children attended at health centers of São Paulo city. The seroprevalence of T. gondii in children from Jardim São Remo was compared to the prevalence in children from other urban centers of Brazil.

Self-diagnosis of active head lice infestation by individuals from an impoverished community: high sensitivity and specificity

To compare sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of self-diagnosis for head lice infestation with visual inspection, we conducted a study in an urban slum in Brazil. Individuals were asked about active head lice infestation (self-diagnosis); we performed visual inspection and thereafter wet combing (gold standard). Of the 175 individuals included, 77 (44%) had an active head lice infestation. For self-diagnosis, sensitivity (80.5%), specificity (91.8%), PPV (88.6%) and NPV (85.7%) were high. Sensitivity of visual inspection was 35.1%. Public health professionals can use self-diagnosis as a diagnostic tool, to estimate accurately prevalence of pediculosis in a community, and to monitor ongoing intervention strategies.

Seroepidemiology of toxoplasmosis in women of childbearing age from a marginal community of Maracaibo, Venezuela

The aim of this study was to determine the prevalence of anti-T. gondii total and IgM antibodies in women of childbearing age. One hundred serum samples of women were studied with age range from 11 to 45 years old. Samples were chosen by random. The determination of total antibodies was carried out through the indirect hemagglutination technique and IgM antibodies by ELISA's technique. The statistical analysis was carried out through the Chi square and the Spearman correlation tests. The theoretical estimated incidence of congenital toxoplasmosis was calculated, according to the annual increment of antibody prevalence among the age groups. The overall prevalence of toxoplasmosis was 33%, while only six individuals (18.2%) were positive to IgM. The highest prevalence was observed in the 11-35 year-old age group. The theoretical estimated incidence was 1.5 for 100 pregnancies in women of 21-25 year-old group; it decreased until 0.1% in the 41-45 year-old age group. The findings show a high prevalence of toxoplasmosis in this community with a high infection risk in women of the studied age group and the high cat population observed, suggesting that the transmission way by contaminated soils may play a main role in the spreading of toxoplasmosis in this community.

Intestinal parasites in a quilombola community of the Northern State of Espírito Santo, Brazil

The aim of this study was to determine the occurrence of intestinal parasites in a quilombola community from the northern Espírito Santo, Brazil. Descendants of slaves who arrived in Brazil in the sixteenth century, this population settled in the municipality of São Mateus in 1858. Fresh fecal samples from 82 individuals who agreed to participate in the study were collected between August 2009 and July 2010, and immediately sent to the Clinical Laboratory of the Centro Universitário Norte do Espírito Santo of the Universidade Federal do Espírito Santo for analysis. Out of all the participants, 36 (43.9%) were male and 46 (56.1%) were female, whose ages ranged from six to 85 years. The study of the occurrence of intestinal parasites indicated that 35 individuals (42.7%) were infected with at least one intestinal parasite. Among helminths, the most frequent were hookworms, with a rate of 14.6%. With regard to protozoa, Entamoeba coli, Entamoeba histolytica/Entamoeba dispar and Endolimax nana stood out, with frequencies of 23.2%, 8.5% and 4.9%, respectively. The occurrence of biparasitism was observed in 13 of the 82 subjects, accounting for 15.8%, and no cases of multiple parasitic infections were observed. It was concluded that the reduction of cases of intestinal diseases due to parasites will only be achieved with the improvement of basic sanitation and quality of life of quilombola populations.

Preliminary study of community-acquired Staphylococcus aureus infection in Manaus Hospital, Amazonia Region, Brazil

Methicillin resistant Staphylococcus aureus is considered a public health problem with a strong potential for dissemination and high rates of morbidity and mortality. In this study we describe bacteriological and epidemiological characteristics of Staphylococcus aureus in Manaus (Amazon region). During the one-year study period (2000-2001), sixteen cases of acute pyogenic multiple abscess were evaluated. Community-acquired S. aureus was identified as causative agent in 10 (62.5%) patients. The strains tested with antimicrobials by discs diffusion method, exhibited a high rate of sensitivity to cephalexin (100%), erythromycin (90%). Oxacillin-susceptible Staphylococcus aureus was 90%. No isolate was resistant to Vancomycin. To our knowledge, no series of community-acquired Staphylococcus aureus in Manaus hospital has been published. Our partial results showed a high rate of antimicrobial sensitivity among community-acquired Staphylococcus aureus in the hospital of Tropical Medicine Institute of Manaus, Amazon Region.