Page:Transactions of the Royal Society of Tropical Medicine and Hygiene, volume 1.djvu/203

 the F. sanguinis hominis was compatible with the perfect health of its host, one of the older observations of Sir Patrick Manson, whom the author had quoted. He (Dr. Low) was by no means satisfied that an infection of F. noctuma was compatible with health in the human subject. For example, filarial embryos might be found in the blood of a patient who had no symptoms and who seemed to be perfectly well, but the future history of the case was the important point. When Dr. Prout read his paper, Dr. Branch recalled the fact that when he (Dr. Low) was in St. Vincent, he had found F. nocturna blood films from two of the nurses at the Colonial Hospital : now he could state that, about five years afterwards, both those women developed elephantiasis. The cases were then entered in his book as " symptoms nil," now they both had elephantiasis. He believed that disease depended on the number of filarise present in individual lymphatics. Then the author had quoted Primrose, who, so far as he remembered, had reported a Barbadian case of filariasis in Canada. Primrose's words were : " It would appear to be the exception for patholo- gical lesions to manifest themselves in persons thus infected," but who his authority for this assumption was he did not say. In the speaker's own paper he had quoted St. Kitts, where 32 per cent, of the people were infected with filaria, and where there was an enormous amount of elephantiasis, chyluria, varicose glands, and filarial abscesses. He had clearly proved that where there was a hicrh endemic index of infection many cases of filarial disease were seen. They had to be carefully looked for, but they were there. For example, in Barbados, the local doctors, knowing he was interested in the subject, often showed him private eases of elephantiasis in whites ; in this way he had seen many manifestations of the disease, which the ordinary individual would have missed. An erroneous impression prevailed that white people did not suffer from