Two monographs on malaria and the parasites of malarial fevers / I. Marchiafava and Bignami, II. Mannaberg.

  • New Sydenham Society
Date:
1894
Catalogue details

Licence: Public Domain Mark

Credit: Two monographs on malaria and the parasites of malarial fevers / I. Marchiafava and Bignami, II. Mannaberg. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    CHAPTBE II. METHODS OP INVESTIGATION. For the investigation of the unstained malarial parasites, the general rules for the microscopic examination of blood are fol- lowed. The preparation of stained specimens, on the other hand, is carried out by a method specially suited to the haematozoon. In order to examine fresh blood for malarial parasites, slides and cover-glasses are carefully cleaned with water and alcohol, and then perfectly dried. The blood is obtained from the tip of the finger or from the edge of the lobe of the ear (which has been previously cleansed with soap and brush), by pricking it with a needle, or, better still, with a small lancet. If the drop of blood so obtained is too large, it is gently mopped up with a linen pledget, and then the part is carefully, but as rapidly as possible, pressed, so that a very small drop of blood exudes. This is immediately caught upon the cover-slip, which is held by a pair of forceps, and placed upon the top of the drop of blood ; after being thus charged, the cover-slip is placed upon the slide, and the drop of blood rapidly spreads itself out between the two glasses. I do not think it is advisable to aid its spread by either pressure or any other method, because I have often found that the blood- corpuscles undergo a change of form if any such mechanical interference is made. It hardly need be said that it is advisable on each, occasion to make several specimens, so that if one is unsuccessful, others will be ready, but before a second or third is prepared one must not neglect to wash away the remainder of the blood from the finger, and to press out a fresh little drop for the next preparation. The necessary size of the drop is soon learnt by experience ; beginners usually take too large a drop. It is especially necessary for the investigation of malarial parasites to have the least possible quantity of blood under the microscope, because in larger quantities the formation of rouleaux interferes with, or even renders impossible, the investigation. Apart from the ordinary microscope slides, I have often used the one recommended by Hay em [80], which has in the centre a