HÆMORRHAGIC SYNDROME OF ALTAMIRA

Abstract

Since January, 1972, a hæmorrhagic syndrome has been observed among immigrants living in forested areas along the newly opened Transamazon Highway in Brazil. Most cases are found around Altamira. The illness is characterised by localised and disseminated cutaneous hæmorrhages, which are associated with mucosal bleeding in 32% of patients. Platelet-counts are reduced, and there is prolonged bleeding-time and poor clot retraction in about half of the cases. The illness was diagnosed as thrombocytopenic purpura. Familial clustering of cases was found, with more children being involved than adults. A few deaths have been attributed to the disease. The precise ætiology of this condition remains obscure. Drugs, alimentary factors, and various viral, rickettsial, and bacterial pathogens do not seem to be involved. Epidemiological and serological evidence suggests that the syndrome is associated with the black-fly, Simulium, and its bite. Case-rates in the Altamira region began to rise shortly after the appearance of large numbers of simulidæ in the rainy season, and fell with the approach of the dry season and virtual disappearance of black-flies. Colonists in this area report intense black-fly biting during the rainy season. The syndrome is not seen among natives of the region, most of whom live in the city of Altamira, where simulidæ are much less common. Patients responded rapidly to steroid therapy, with platelet-counts returning to normal within a few days. The disorder has been named the hæmorrhagic syndrome of Altamira.