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a Loa from other parts of the body than the eye have been received with some caution by helminthologists. This is clearly shown by the silence of Manson, Blanchard, and other authorities on this point, even though they cite in connection with some cases in the eye the popular opinion that such worms occur elsewhere in the body. In the present case we have the best of evidence, since the specimens in question were removed by a medical man, and on account of the importance of the matter I have subjected them to most careful scrutiny. While one is not in sufficiently good condition to render an absolute decision possible, there can be no doubt as to the systematic position of the other specimen. Accordingly, it may now be affirmed that the F. loa does make its appearance near the surface in other parts of the body than the eye. Since Dr. Vail has in preparation a paper to be read before the American Academy of Ophthalmology and Oto-laryngology at Buffalo in September, 1905, I forbear to trench further upon his field and refer to his paper for further details regarding these cases and for a discussion of the clinical factors.
2. Cases Of F1lar1a Loa On Record
Many authors have assembled the earlier records of this parasite, but in general the lists given have been inaccurate and imperfect. The series given by Blanchard (1899) is admirable in manner of treatment and is the most complete. It includes twenty-five previous cases and one new one. The method employed of listing all records quoted from a given paper as one case under the name of the author seems to me undesirable since it does not distinguish between the account of a single chance specimen and more extended observation. Here each case includes the history of only a single host, so far as this could be fixed, even though two or more parasites were removed from the one individual. If this method be criticised as incomplete, one can only reply that it is impossible to determine whether the multiple infection took place at a single time or through repeated introduction of the parasite. Only the positive demonstration of the latter condition would justify the interpretation of the numerous parasites as separate cases of the disease. I have departed from this rule twice where the time interval was such as to justify the acceptance of the later record as a new case. So far as possible each case record includes the name, date, and place of observation, the sex, age, and nationality of the person infected, the number and sex of the worms, a statement regarding their removal, if accomplished, and the probable place and time of infection, and finally the place and date of publication. In some cases only a limited amount of data are given by the original recorder, and in many instances certain of these desiderata are lacking.
By no means all of the cases of which we have reasonably good information are included in the list, since some of the records, though distinct, are not definite enough to enumerate exactly in such a series. Thus Guyot (1805) speaks of several other individuals, on the coast of Angola; Wilson's patient says (Wilson, 1890) the disease is common among natives, and all the missionaries of that station, Benita near Gaboon, have them; Robertson's patient had seen such cases in the eyes of natives; Roth (1896) says his patient informed him that a number of people in her village complained of the same disease; while Miss Kingsley, the well-known African traveler, speaks of these filariae as abundant and fairly common in different regions on the West Coast of Africa. Such evidence might be multiplied concerning this part of the world.
Not all cases are equally clearly established. I have followed the general custom of previous authors in including cases in which the identity of the parasite has not been finally demonstrated. Indeed, were one to demand precise identification all the earlier cases and many of the later ones must be thrown out. Again, other species have been reported from the eye of man and some of those doubtfully attributed to F. loa in this list may belong to such species. In such cases the geographical location of the case or the past record of the infected person are of importance in determining the probable species of Filaria represented. Even thus no case has been included in this list except the weight of evidence was strongly in favor of the interpretation given. Under this treatment the total number listed becomes ninety-four, from the record of Mongin published in 1770 to those of the current year (1905), a time interval of 135 years. About two-thirds fall within the last twenty years, and half the total number have been published within the ten years from 1896 to date.
The matter of the earliest record calls for a word of comment. Pigafetta (1525) has been cited by Guyon (1864), Manson, Moniez (1896), and Blanchard (1886, 1899) as evidence of the occurrence of Filaria loa in Africa in the sixteenth century. This claim is based upon a plate, one figure of which is interpreted by these authors as illustrating the removal of an eye worm. It appears that this plate does not belong to Pigafetta's works, but to Lindschoten's; and even here it is not found in the original edition (1596), but occurs first in the De Bry reprint where it was probably inserted by the publisher. I have discussed the matter in detail elsewhere (Ward, 1905). The region described by Lindschoten lies in the Persian Gulf, and not in the Congo territory, where Guyon et alii located the account. It is thus well within the range of Dracunculus medinensis, but far removed from the habitat of Filaria loa. Furthermore the text makes no mention of infected eyes, but speaks of "worms in the legs" of the natives, which again accords with the Guinea worm. Hence the interpretation placed upon the plate must be rejected, and if, indeed, the plate itself has any standing as evidence, it concerns the Guinea worm rather than Filaria loa. This reference must accordingly be eliminated from discussions of the latter species. It is not listed here among the cases of F. loa which I have collected, verified, and arranged as follows:
1. Mongin at St. Domingo in 1770 records the extraction of one worm from between the conjunctiva and albuginea of a negress.
2. Bajon at Cayenne in 1768 removed a worm from below the conjunctiva of a negress eight years old; this case was first published in 1777 together with the following.
3. Also at Cayenne in 1771 Bajon observed in an older negress such a worm moving across the eye between conjunctiva and cornea, but was not allowed to remove it.
4. Mercier at St. Domingo in 1771 extracted a worm from beneath the cornea of a negress.
5. The same authority in 1774 removed from a negro a worm which lay above the cornea. The record of cases 4 and 5 was published by Arrachart in 1805.
6. Arrachart notes that in 1795 Mlle. L. Fraise, creole, born in ,St. Domingo, assured him that her brother had several times such worms in his eyes at the age of three to five years; they were successfully extracted. She also adds that young negroes were often attacked. This striking note seems to have been overlooked by students of the subject. The direct implication that the child was born in St. Domingo would indicate the existence there at that time of a center of infection for F. loo, such as is known to have existed for the Guinea worm (Dracunculus medinensis) at several points in the Western Hemisphere during the continuance of the slave trade. The alternative that some other species was involved seems less acceptable as there are no other records favoring this view, unless the South American cases indicate the rare occurrence there of a native species similar in habit to F. loa.
7. The French naval surgeon, Guyot, made several voyages to the coast of Angola. On one occasion, examining closely the eye of a negress, he saw what seemed to be a varicose vein in the conjunctiva, but when he touched it with the point of a lancet the object disappeared. It appeared several times in the same patient at irregular intervals, and he thought that between times the worm retired to the posterior region of the orbit. He recorded the native name of Loa, the common occurrence of the malady, the irregular appearances of the worm in the eye, and the inefficacy of all medication. The case was first published in Arrachart, 1805.
8-12. In 1777 Guyot made a new voyage to the coast of Angola. He observed again this verminous ophthalmia among the negroes of the Congo, and in two cases out of five succeeded in removing the worms. The account of these cases was first published by Arrachart (1805:228, observations 7 ff.) and later by Rayer (1843). Guyot was the first to view this species as different from the Guinea worm. He says: "Je ne crois pas que ces vers soient de l'espece du dragoneau, car ils sort tres blancs, plus dur et mois longs a proportion. Je ne jamais vu ce ver se faire jour de lui-meme. Pendant sept voyages que j'ai fait a la cote d'Angola, je n'ai vu aucun negre attaque du dragoneau. Plusiers chirurgiens qui ont navigue sur ces cotes m'ont assure n'en avoir jamais vu."
13. M. de Lassus, army health officer of St. Domingo, removed a worm from the eye of a negro. The case is chronicled by Larry, 1812.
14. In 1828 a worm was seen in the orbit of a negress, recently arrived as a slave from Africa at Monpox, a village on the banks of the Magdalena river in United States of Columbia. This observation is attributed unmistakably by the original text to Clot-Bey, a French surgeon, well known for his work in Egypt about that date. The French authors agree in pronouncing this authorship an error and in substituting the name of Roulin. T have found neither explanation nor reference to Roulin or his works.
15. Dr. Blot, a physician on Martinique, in 1837 removed two filariae from the eye of a young negress who had come from the African Coast. One was sent to Guyon and Blainville, and described by the former (Guyon, 1838).
16-17. Loney, an English naval surgeon, in April and June, 1842, extracted moving worms from beneath the conjunctiva of two Kroomen on the West Coast of Africa. He reported these cases together in 1844.
18. Lallemant excised a worm from the eye of a negro in Rio de Janeiro, and in 1844 published a description of the case.
19. In 1833 Christovo Jose dos Santos removed a worm from the orbit of a Mina negress. Sigaud witnessed the operation and reported it in 1844.
20. Lestrille in 1854 removed a worm from the eye of a negro at Gaboon; his description of the case was published by Gervais et Van Beneden (1859).