Dr. Daniel's report to the secretary of the Malaria Investigation Committee of the Royal Society, London, on the results of investigations made by him in Calcutta in conjunction with Major Ross, I.M.S.

  • Charles Wilberforce Daniels
Date:
[1899]
Catalogue details

Licence: Public Domain Mark

Credit: Dr. Daniel's report to the secretary of the Malaria Investigation Committee of the Royal Society, London, on the results of investigations made by him in Calcutta in conjunction with Major Ross, I.M.S. Source: Wellcome Collection.

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    (b) Cysts fall of germinal threads, other ruptured empty cysts, germinal threads in body fluids, germinal threads in salivary glands. Over 20 observations. (r) Empty cysts in stomach wall, germinal threads in body fluids of thorax. Germinal threads in salivary glands. No cysts still con¬ taining germinal threads. 2 observations. (d) Empty cysts only in stomach wall, no germinal threads in body cavity, no germinal threads in well exposed salivary glands. One observation, the mosquito had been infected four weeks before death. These observations fully confirm Ross’ statements in every point. They indicate that the threads are formed in the coccidia, that they escape on the rupture of these into the body cavity and are again collected in the salivary glands. I should have liked to extend the series, but the continued cold weather renders it improbable that I shall be able to do so before I leave. 10. With your permission I should like to publish an abstract of this, con¬ firming Ross’ work; and to this Major Ross consents. In case you should consider this advisable I am, to avoid delay, forwarding an abstract to Dr. Manson, with a request to him to forward it to the British Medical Journal, if your consent is granted. 11. The infection of birds free from proteosoma by the bites of mosquitoes. On December 20th the day before my arrival 22 birds were examined and found free from proteosoma. On that night some of these were used for feeding the mosquitoes which had been infected on November 30th and on the 24th and subse¬ quent days; the remainder of the birds were used for feeding the mosquitoes first infected on November 30th and December 10th, 12th and 15th. In other mos¬ quitoes of this series germinal threads were found in the salivary glands; and the ones which fed, when examined later, gave the results indicated in paragraph 9. On December 30th Dr. Rivenberg and myself examined these birds; 3 of them had proteosoma, 2 in large numbers. On January 4th I examined them all except one which died on January 2nd ; in that the heart’s blood contained no proteosoma and the organs were free from pigment. Five more of these had now proteosoma, all very numerous. On January 6th and 7th I again examined them; 3 more had proteosoma all very numerous. On January 9th no more cases had developed. But on January 18th one of them had numerous proteosoma; whilst many of the ones which had been infected had recovered, and the others now showed few proteosoma. Thus 12 out of 22 birds became infected or 54 per cent. This compares unfavourably with Ross’ earlier results, as, in his published series, 22 out of 28 were infected, or 79 per cent. But it is to be remembered that at the time he was working the germinal threads were found in a week; whilst in December the development was much slower, and now takes at least twice the time. It is much easier to keep the mosquitoes alive for one week than longer, while in the hot weather mosquitoes bite more readily. These results are less unfavourable, if compared with the normal proportion of birds infected with proteosoma at this season. Thus Ross out of 111 wild birds found proteosoma in 15 or 13*5 per cent; whilst I find at this season only one with proteosoma out of 30 or 3*3 per cent. It is possible that in the cold season the birds have a greater power of resistance; and this is rendered more probable by the short duration of the proteosomal attack in my infected birds. Of these 12, 5 died within the first week. In 3, in which also the proteosoma had heen very numerous, none could be found 10 days after the invasion ; in one in which they were never numerous none could be found on the fifth day. In the other 3, very few are now found; though at first they were numerous
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