Sylvia Amaral Gurgel Vellosa

A COMPARATIVE EPIDEMIOLOGIC STUDY OF SPECIFIC ANTIBODIES (IgM AND IgA) AND PARASITOLOGICAL FINDINGS IN AN ENDEMIC AREA OF LOW TRANSMISSION OF Schistosoma mansoni

The diagnostic potential of circulating IgM and IgA antibodies against Schistosoma mansoni gut-associated antigens detected by the immunofluorescence test (IFT) on adult worm paraffin sections was evaluated comparatively to the fecal parasitological method, for epidemiological purposes in low endemic areas for schistosomiasis. Blood samples were collected on filter paper from two groups of schoolchildren living in two different localities of the municipality of Itariri (São Paulo, Brazil) with different histories and prevalences of schistosomiasis. The parasitological and serological data were compared to those obtained for another group of schoolchildren from a non-endemic area for schistosomiasis. The results showed poor sensitivity of the parasitological method in detecting individuals with low worm burden and indicate the potential of the serological method as an important tool to be incorporated into schistosomiasis control and vigilance programs for determining the real situation of schistosomiasis in low endemic areas.

Ocorrência de Strongyloides stercoralis em pacientes portadores da síndrome de imunodeficiência adquirida (AIDS)

A comparative study on the occurrence of Strongyloides stercoralis larvae in 554 patients with AIDS and in 142 patients suffering from infectious diseases other than AIDS was conducted during the period from January 1987 to December 1988. The two groups was constituted by male individuals in-patients at Emilio Ribas Hospital - Sao Paulo. Faeces samples from 696 patients were submitted to spontaneous sedimentation method and Rugai method. The data obtained from the present investigation demonstrated a similar prevalence of Strongyloides stercoralis in both groups (p > 0.05) indicating no significant statistical differences.

Synthesis and evaluation of new oxamniquine derivatives

Oxamniquine derivatives were synthesized and evaluated as novel schistosomicide agents. Oxamniquine (1,2,3,4-tetrahydro-2-[[(1-methylethyl)amino]methyl]-7-nitro-6-quinolinemethanol) was submitted to the Mannich reaction, using formaldehyde, paraformaldehyde and acetaldehyde as reagents, and gave three unexpected products: two of them were cyclized on the alkylamine side chain and another etherified on the aminequinolinemethanol group. The three compounds were biologically evaluated using mice infected with Schistosoma mansoni and showed promising activities, but had higher toxicities. For studies on structure-activity relationships, results demonstrate that the side alkylamine group can be modified with preserved activity, but that this modification is associated with increased toxicity.

Ocorrência de Taenia sp. na população atendida no laboratório central do Instituto Adolfo Lutz, São Paulo, SP, Brasil (1960/1989)

Foram examinados retrospectivamente os relatorios mensais e anuais da Secao de Enteroparasitoses do Laboratorio Central do Instituto Adolfo Lutz, Sao Paulo, SP, do periodo de 1960 a 1989, perfazendo uma serie historica de 30 anos, com 1.519.730 exames protoparasitologicos e 355 identificacoes de proglotes de Taenia. Pelo metodo da sedimentacao espontânea foram diagnosticados 7.663 (0,5%) casos de presenca de ovos de Taenia sp. nas fezes. Das 355 proglotes enviadas para identificacao, 311 (87,60%) estavam em condicoes de serem especificadas, e dessas, 273 (87,80%) eram proglotes de Taenia saginata e 38 (12,22%) de T. solium.Monthly and yearly reports of the Seção de Enteroparasitoses of the Instituto Adolfo Lutz (São Paulo, SP, Brazil) from 1960 to 1989 with 1,519,730 parasitological stool examinations were studied. There were also 355 identifications of Taenia sp. proglottids. Using Hoffman, Pons & Janers method, 7,663 (0.5%) cases of taeniasis were diagnosed, and 311 (87.60%) of the 355 proglottids were on easy terms to be specified, 273 (87.80%) of them were from Taenia saginata.

IgM antibodies to Schistosoma mansoni gut-associated antigens for the study of schistosomiasis transmission in Ribeirão Pires, São Paulo

The potential of an immunofluorescence test for detection of IgM antibodies against Schistosoma mansoni gut-associated antigens (IgM-IFT) was evaluated as a tool for studying aspects related to the schistosomiasis transmission in Ribeirão Pires, in the metropolitan area of the capital of the State of São Paulo, Brazil. Children from a school with about 400 students, 6 to 18 years, were followed-up for two years. In the five surveys, carried out at 6-month intervals, from October 92 to October 94, serological (IgM-IFT) prevalence indices of 5.3%, 5.8%, 6.2%, 2.9% and 3.3% were obtained. These indices were 7 to 10 times higher than the parasitological prevalence indices of 0.5%, 0.5%, 0.7%, 0.4% and 0% determined by the Kato-Katz method. Seroconversion from IFT negative to positive was indicating possible newly acquired S. mansoni infection in three children. But confirmation of infection by fecal examination was possible in only one child. The IgM-IFT can constitute a valuable tool for the improvement of the vigilance program in low endemic areas for schistosomiasis, better characterizing the S. mansoni transmission in such areas.