ONCHOCERCIASIS in Brazill Mário A. P. Moraes,2 Habib Fraiha,3 And
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Reprint (rom the -' Bullet;n of lhe Pan American Health Organ;zation Vol. VII, No.4,1973. ONCHOCERCIASIS IN BRAZILl Mário A. P. Moraes,2 Habib Fraiha,3 and GeovaneM. Chaves4 An endemic focus of onchocerciasis, the so-called "river blindness" widespread' in parEs of Africa, has' been dis- covered in Brazil. Until recently the only confirmed foci in this Hemisphere were in Guatemala, Mexico, Colombia, and Venezuela. The research confirming this new Brazilian focus indicares the disease has spread over a fairly large swath of backlands in the vicinity of the Brazil- Venezuela border. Introduction 1967. Unfortunately, diagnosis of the case did not stimulate research aimed at finding The presence of the filaria worm Oncho- the focus of the disease. cerca volvulus in the New World has been In 1972 Moraes and Dias (10) reported known since 1915, when Robles (4, 12) finding two other cases in American woman discovered it in Guatemala. But until a missionaries living on the Toototobi River short time ago the known endemic areas of in the State of Amazonas among Indians of onchocerciasis in the Americas were lirnited the Waica Tribe, a subdivision of the Ya- to Guatemala, Mexico, and Venezuela (1, nornarna Indian group. Both women had 3). Isolated cases reported in Surinam (7) nodules in the sacral region that were sev- and Ecuador (8) could not be confirmed. eral years old. The diagnosis was made by Then in 1970 Little and D'Alessandro chance, in the course of a routine histo- (9) described the first focus in Colombia, pathologic exarnination. Some months later situated in a number of places along the Mi- a new case, originating in the same area, cay River. According to the authors, how- was discovered by Moraes and Chaves (11). ever, this focus was confined to a relatively The patient was yet another American smalI area. O. volvulus infections were de- woman rnissionary living among the Waicas, tected in 44 of 292 individuaIs exarnined, this time in the Surucucus Mountains of almost alI of whom were Negroes. the Roraima Territory. AlI three of these Only one indigenous case had previously patients were treated with diethylcarbama- been found in Brazil; it was discovered in zine (Hetrazan); the drug was also admin- the far-north Federal Territory of Roraima, istered to the husband of one of the and was described by Bearzoti, et ai. (2) in women after he complained of severe pru- figo of the thighs and buttocks. 1Also appearing in Portuguese in Boletín de Ia Oficina Sanitaria Panamericana (January 1964). The fact that the rnissionaries were living 2Associate Professor at the Federal University in contact with the Waicas, in the extreme of Pará, Belém, Brazil; and Pathologist, Evandro northern part of Brazil near the Venezuelan ChagasInstitute, Belém, Brazil. 3Parasitologist, Evandro Chagas Institute. Holder border, and the fact that the Venezuelan of grant from the National Research Council of Indians of the same Yanomama group cus- Brazil, TC n. 02712/72. tornarily crossed the border to visit villages 4Medical student at the University of Amazo- nas, Manaus, Brazil. on the Brazilian side, caused us to suggest SO ~ Moraes, et ai. .ONCHOCERCIASIS IN BRAZIL SI (11) that a focus of onchocerciasis might river, some insects of the vector genus extend throughout the parts of Brazil and Simulium were captured. These are known Venezuela inhabited by the Yanomamas.To throughout the Amazon region by the name verify this hypothesis, in July 1973 we of "pium," but the Waicas caU them travelled to the Toototobi River arfa, where "okuxib." However, this report covers only the first two rnissionary patients were still the finding of O. volvulus parasites among living. Apart from the parasitologic examina- those lndians that we were able to ex- tion of the lndians in villages along the amine. MAP l-A hydrographic map of the northwestem Amazon indicating the location of the Toototobi River. Materiais and Methods Mission of the New Tribes of Brazil) estab- lished their posto The Toototobi River is a small tributary To avoid isolation of this mission facility of the Demini (Map 1), which in turn is a for most of the year, a small airplane land. tributary of the Rio Negro. According to ing strip was built about one kilometer the classification system used for the rivers from the lndian village. The authors travel- of the Amazon Basin, it can be considered led there in a light airplane (belonging to a Tiver of "white water," that is, its water another religious group) that is commonly carries a large quantity of suspended clay used to transport missionaries and supplies particles. The area is very hard to reach by between Boa Vista (capital of the Roraima boat because rapids in the Demini are only Territory) and various mission posts that navigable during a short period each year dot the frontier region. The distance from when the Tiver is at flood stage. However, Boa Vista to the Toototobi post is about there are a number of Waica villages along 200 miles. its banks, and it was near one of these lndians from three villages on the Too. that the inissionaries (affiliated with the totobi were ex~iiled. The location of 52 P~Q~U~~-~~~~~~ MAP 2- The Toototobi River region, with the approximate location of the three villages surveyed: Chief Roberto's viUage (1), Chief Plinio's viUage (2), and Chief Fialho's viUage(3). ~ these villages,whose chiefss were called Ro- Even if no microfilaria were found, the berto, Plinio, and Fialho by the mis- examination continued with an immediate sionaries,is shown in Map 2. According to search, prirnarily by palpation, for subcuta- a census taken by the rnissionaries,Rober- neous nodules. Missionaries' reports (11) to's village, Plinio's village, and Fialho's vil- had already informed us that the nodules lage had respective populations of 80, 52, were very hard to see, and this fact Was and 22 persons. confirmed during the examinations. One The first step in the examination con- characteristic of these nodules, known as sisted of taking a skin sample from each onchocercornas,is their high degree of mo- subject w'ith small scissors.This was obtain- bility in the subcutaneous tissue. They ed from the area of the shoulder blades if could quite readily be rolled around with no cutaneouslesions were observed;if there the index finger. were manifestations apparently attributable We were able to remove nodules from tó O. volvulus, however, the tissue was three Indians for histopathologic examina- taken from the affected area. The material tion. Another nodule was also removed obtained was placed in a drop of saline from one of the missionaries,whose case solution on a glassslide and covered with a was the first previously reported by Moraes coverslip. It was then warmed slightly and and Dias (10). exarnined at once for rnicrofilaria; if the first exarnination proved negative, the ma- terial was exarnined again ten minutes later. Results 5The Waicas do not use the terms, tuxaua, A total of 91 Indians (49 men and 42 cacique, or morobixaba. In their language the Chiei is the "one who talks," or in other words women) from the three villages were exam- the one. who gives orders. ined. Of this total, 41 persons (23 men MAP 2- The Toototobi River region, with the approximate location of the three villages surveyed: Chief Roberto's viUage (1), Chief Plinio's viUage (2), and Chief Fialho's viUage(3). Moraes, et aL .ONCHOCERCIASIS IN BRAZIL 53 and 18 women) were from Roberto's vil. in 10 of the 57 Indians with microfilaria, lage, the one closest to the rnission post; and also in one Indian wcman whose skin 36 persons (18 meu and 18 women) were test rernained negative even after a second from Plinio's village; and 14 (8 meu and 6 biopsy. In seven of these cases, including women) were from Fialho's village. that of this woman, the nodules were 10- Biopsy of the skin samplesshowed that calized principally in the scalp. In the three 57 Indians (30 meu and 27 women) were previously mentioned instances in which the infected with O. volvulus microfilaria. In detected nodules were actually removed other words, the results were 62 per cent from Indian subjects, histopathologic exam- positive, being slightly higher for the wom. ination revealed the presence of O. volvulus en (64 per cent positive) than for the meu in each case. In one nodule the filariae (61 per cent positive). The rate of positive were already in a state of degeneration. It findings for samples from each village was is probable that some onchocercomas es- 65 per cent for Roberto's village, 81 per caped notice during the examination, which cent for Plinio's village, and 57 per cent was somewhat hurried. If so, the small size for Fialho's village. and often very deep location of the nod- Ages of the positive cases ranged from ules were most certainly contributory fac- 13 to 58 years. af those in the 40-and- tors. over age group, ali of the individuaIs tested ane Indian ma~ and woman with micro- (a total of 13) were infected with micro- filaria in their skins (both from the village filaria (see Figure 1). Unfortunately, the of Chief Roberto) were blind in one eye. youngest Indians whom we could examine Another Indian woman, from the village of were already at least 10 or 11 years of Chief Fialho, complained of severe photo. age. According to the beliefs of the Yano- phobia when the biopsy was being taken. mamas, children's souls are not yet firmly We confirmed that she was suffering from lodged in their bodies and mar escape blepharoconjunctivitis, which had already through their mouths if they cry.