Alejandro Luquetti Ostermayer

Soroprevalência de tripanossomíase americana em adultos de uma área da Amazônia ocidental Brasileira

From January to March 2001 a seroepidemiological survey for American trypanosomiasis (Chagas disease) was carried out among urban and rural human populations in areas of the Upper Purus basin, in the western Brazilian Amazon region, using serial testing with three different serological techniques. The sample was composed of 1,055 individuals: 844 from urban and 211 from rural areas. Autochthonous infection was identified in nine individuals aged 16 to 72 years: five from urban and four from rural areas. The estimated prevalences of Chagas infection for the urban and rural areas were 0. 6% (95% CI: 0. 2-1. 4) and 1. 9% (95% CI: 0. 6-4. 5) respectively. An apparent clustering trend was noted: seven were born along the Purus river: three lived at the same locality and two of them in the same dwelling.

Study on Chagas disease occurrence in the municipality of Monte Negro, State of Rondônia, Brazilian Amazon

INTRODUCTION Studies on Chagas disease deal with the perspective of its occurrence in the Amazon region, which is directly correlated to the population growth and the spread of the bug biotope. The state of Rondônia has an immense source of vectors (Triatomine) and reservoirs of Trypanosoma cruzi. Environmental changes brought forth by the deforestation in the region may cause vector behavior changes and bring these vectors to a closer contact with humans, increasing the probability of vector infection. METHODS This study was carried out to check the occurrence of Chagas disease in the municipality of Monte Negro, Rondônia, Brazil, based on a random sampling of the farms and people wherein blood collection from the population and capturing triatomines were done. The blood samples were submitted to serologic tests to detect antibodies of the IgG class against T. cruzi. The triatomines that were collected had their digestive tract checked for the presence of trypanosomatidae with morphology resembling that of the T. cruzi. RESULTS The population examined was mostly from other states. From the 322 bugs examined on the microscope, 50% showed parasites with morphology compatible with T. cruzi. From the serology of 344 random samples of human blood, 1.2% was found positive, 6% showed inconclusive results, and 92.8% were negative. CONCLUSIONS Monte Negro shows low prevalence of human infection by T. cruzi and none active vector transmission; however, preventive and surveying measures, which are not performed until now, shall be taken due to the abundance of vectors infected by trypanosomatidae.

Genetic polymorphism among six Trypanosoma cruzi stocks isolated from chronic chagasic patients

Laboratório Dra. Maria do Carmo Moreira de Souza, Departamento de Parasitologia, Instituto de Patologia Tropical e Saúde Pública, Rua Delenda Rezende de Melo, s/no, Setor Universitário, 74605-050 Goiânia, GO, Brasil *Laboratório de Biologia Molecular, Instituto de Ciências Biologicas **Laboratório de Pesquisa da Doença de Chagas, Hospital das Clínicas, Universidade Federal de Goiás, Goiânia, GO, Brasil

Human lagochilascariasis—A rare helminthic disease

Lagochilascariasis is a parasitic disease caused by a helminth of the order Ascaroidea, genus Lagochilascaris that comprises 6 species, among which only Lagochilascaris minor Leiper, 1909, is implicated in the human form of the disease. It is remarkable that the majority of cases of human lagochilascariasis in the Americas have been reported in Brazil. The natural definitive hosts of this parasite seem to be wild felines and canines. Lagochilascariasis is mostly a chronic human disease that can persist for several years, in which the parasite burrows into the subcutaneous tissues of the neck, paranasal sinuses, and mastoid. L. minor exhibits remarkable ability to migrate through the tissues of its hosts, destroying even bone tissue. Fatal cases have been described in which the parasite was found in the lungs or central nervous system. Treatment is often palliative, with recurrence of lesions. This paper summarizes the main features of the disease and its etiologic agent, including prevalence, life cycle, clinical course, and treatment.